diff options
Diffstat (limited to 'hurd')
34 files changed, 3726 insertions, 103 deletions
diff --git a/hurd/coding_style.mdwn b/hurd/coding_style.mdwn new file mode 100644 index 00000000..cc1e3cf3 --- /dev/null +++ b/hurd/coding_style.mdwn @@ -0,0 +1,59 @@ +[[!meta copyright="Copyright © 2013 Free Software Foundation, Inc."]] + +[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable +id="license" text="Permission is granted to copy, distribute and/or modify this +document under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no Invariant +Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] + +[[!tag open_issue_documentation]] + +Some coding style comments that are specific to Hurd systems. + +[[!toc]] + + +# Freeing Port Rights + +## IRC, freenode, #hurd, 2013-07-01 + + <teythoon> do I have to explicitly free ports in a short lived process like + mount? + <pinotree> better take the habit of doing that anyway + <teythoon> how do I recognize that I have to free something? mig spec? + <braunr> i'd say no + <braunr> mig does it for you + <braunr> gnumach reference manual + <teythoon> not memory, like port rights + <braunr> but no, really, for short lived processes it's ok + <braunr> yes, port rights + <braunr> like memory, you don't free stuff in short lived processes :p + <braunr> mach does it correctly when the task is destroyed + <braunr> but there are two use cases for rights + <braunr> those you create manually + <braunr> and those mig creates for its own purpose + <braunr> ignore those used by mig, they matter only in very specific parts + of glibc and other very low level stuff + <braunr> teythoon: keep in mind that there are two flavours of resources + with port rights + <teythoon> but how do I *know* from looking at say fs.defs that I have to + free anything I get? + <braunr> rights themselves, and the user reference count per right + <braunr> eh, that's complicated + <braunr> in a complete RPC call, you must watch two things usually + <braunr> out of line memory + <braunr> and right references + <braunr> except otherwise mentioned, you don't have to free anything + <braunr> freeing passed memory should be obvious (e.g. "out" keyword on a + memory range) + <braunr> for right references, it's less obvious + <braunr> refer to the mach server writing guide i guess + <teythoon> what does the dealloc qualifier do in mig defs? + <braunr> basically, send rights can be created from a receive right + (make_send), or another send right (copy_send) + <braunr> it tells mig which function to call once an RPC has returned + <braunr> all this is described in the mach server writing guide + <braunr> and it's tricky + <braunr> quite error-prone so check with portinfo diff --git a/hurd/console/discussion.mdwn b/hurd/console/discussion.mdwn index f887d826..0022ec23 100644 --- a/hurd/console/discussion.mdwn +++ b/hurd/console/discussion.mdwn @@ -1,4 +1,4 @@ -[[!meta copyright="Copyright © 2012 Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2012, 2013 Free Software Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this @@ -10,6 +10,8 @@ License|/fdl]]."]]"""]] [[!tag open_issue_documentation]] +[[!toc]] + # IRC, OFTC, #debian-hurd, 2012-09-24 @@ -40,3 +42,9 @@ License|/fdl]]."]]"""]] hacking? <allesa> to fix that is… <youpi> some hacking yes + + +# IRC, freenode, #hurd, 2013-07-10 + + <pinotree> http://xkbcommon.org/ ¡û sounds interesting for our console + translator diff --git a/hurd/debugging.mdwn b/hurd/debugging.mdwn index f4b5eba5..ae9b7bef 100644 --- a/hurd/debugging.mdwn +++ b/hurd/debugging.mdwn @@ -26,3 +26,30 @@ License|/fdl]]."]]"""]] * [[glibc]] * [[translator]]s * [[trap_in_the_kernel]] + + +# IRC, freenode, #hurd, 2013-06-30 + + <hacklu> braunr: I don't understand your question totally, but I want to + know how do you do this inspecting? <braunr> i have a small test program + that creates a thread, and inspect its state before any thread dies + <braunr> i use portinfo + <braunr> and rpctrace + <braunr> (there is also vminfo but you're not likely to need it for what + you're doing right now) + <hacklu> I have used rpctrace before, but portinfo, I will try it. + <hacklu> is portinfo show a process's all port use log? + <braunr> not log + <braunr> current state + <hacklu> dump the port name space? + <braunr> yes + <hacklu> I found some names are not continuous. how this come out? + <braunr> continuous ? + <hacklu> 101:send 103:send + <hacklu> missing 102 + <braunr> some are freed + <braunr> a lot actually + <braunr> every RPC needs a reply port + <braunr> a temporary receive right to get replies from servers + <hacklu> so we can reuse the name which are freed before + <braunr> of course diff --git a/hurd/debugging/rpctrace.mdwn b/hurd/debugging/rpctrace.mdwn index a5c1a6e9..d62a4387 100644 --- a/hurd/debugging/rpctrace.mdwn +++ b/hurd/debugging/rpctrace.mdwn @@ -16,6 +16,17 @@ doing. See `rpctrace --help` about how to use it. +# IRC, freenode, #hurd, 2013-07-29 + + <teythoon> about rpctrace, it poses as the kernel for its children, parses + and relays any messages sent over the childrens message port, right? + <braunr> teythoon: rpctrace doesn't "poses as the kernel" + <braunr> well, it's close enough + <teythoon> but it intercepts messages send by its children by handing them + a message port different from the one provided by the kernel, doesn't it? + <braunr> yes + + # Issues and Patches [[!tag open_issue_hurd]] @@ -182,6 +193,38 @@ See `rpctrace --help` about how to use it. <youpi> uhu, there's a TODO just above that assertion :) +* IRC, freenode, #hurd, 2013-07-05 + + <pinotree> wish: make rpctrace decode the results of io_stat rpcs + +* IRC, freenode, #hurd, 2013-07-29 + + <teythoon> imho rpctrace is kind of a mess right now :-/ we should move the + parsing code to a library + <teythoon> that would also be useful for valgrind, it should have to do + basically the same + +* IRC, freenode, #hurd, 2013-07-29 + + <teythoon> and I tried to rpctrace a subhurd, but rpctrace died on a + assertion failure, some msg had an unexpected type or something + <braunr> rpctrace dies on select + <braunr> and guess what, the boot tool does call select on the console it + emulates + <teythoon> that's a shame, that'd be really useful for me + <braunr> it might not be hard to fix + <braunr> but i've never looked into it :/ + <braunr> i only saw that rpctrace expects the common RPC message types + <braunr> and select is all but a common RPC + <braunr> so the type of the messages involved is slightly different + <braunr> and the assertion chokes on that + <teythoon> rpctrace.c is huge and hand written, it'd be nice if the parser + was created from the procedure definitions + <teythoon> and thinking of that, mig does exactly that, one would only need + some glue code + <braunr> select is partially hand written + <braunr> but it's a special case so that's ok + # See Also diff --git a/hurd/libfuse.mdwn b/hurd/libfuse.mdwn index 45ff97ec..78e96022 100644 --- a/hurd/libfuse.mdwn +++ b/hurd/libfuse.mdwn @@ -29,6 +29,26 @@ etc. * File I/O is quite slow. +## IRC, freenode, #hurd, 2013-05-31 + + <zacts> well the reason I'm asking, is I'm wonder about the eventual + possibility of zfs on hurd + <pinotree> no, zfs surely not + <zacts> *wondering + <zacts> pinotree: would that be because of license incompatabilities, or + technical reasons? + <pinotree> the latter + <taylanub> It's just a matter of someone sitting down and implementing it + though, not ? + <pinotree> possibly + <braunr> zacts: the main problem seems to be the interactions between the + fuse file system and virtual memory (including caching) + <braunr> something the hurd doesn't excel at + <braunr> it *may* be possible to find existing userspace implementations + that don't use the system cache (e.g. implement their own) + <braunr> and they could almost readily use our libfuse version + + # Source [[source_repositories/incubator]], libfuse/master. diff --git a/hurd/libstore.mdwn b/hurd/libstore.mdwn index 8eac39fe..b2e7f7a9 100644 --- a/hurd/libstore.mdwn +++ b/hurd/libstore.mdwn @@ -1,4 +1,4 @@ -[[!meta copyright="Copyright © 2007, 2008, 2009 Free Software Foundation, +[[!meta copyright="Copyright © 2007, 2008, 2009, 2013 Free Software Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable @@ -6,8 +6,8 @@ id="license" text="Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license -is included in the section entitled -[[GNU Free Documentation License|/fdl]]."]]"""]] +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] `libstore` is used to provide a generic interface to access data (read/write) on backing stores. @@ -15,6 +15,8 @@ on backing stores. It more than just a thin layer between [[GNU Mach|microkernel/mach/gnumach]] devices (`hd0` for example) and the device node below `/dev/`... +[[!toc]] + # Available Stores @@ -34,3 +36,32 @@ can be found. pages="hurd/libstore/examples/* and !*/discussion" show=0 feeds=no]] + + +# Open Issues + +## IRC, freenode, #hurd, 2013-07-29 + +[[!tag open_issue_documentation open_issue_hurd]] + + <teythoon> and I read hammys paper about mobile code, is it true that the + store code is loaded into the client? who is the server and who is the + client in this context? + <braunr> teythoon: "store code" ? + <teythoon> libstore + <braunr> the hurd libstore ? + <teythoon> yes + <braunr> hum, what paper ? + <teythoon> braunr: + http://users.student.lth.se/cs07fh9/2009-hammar-hurd-mobility.pdf + <braunr> how nice + <tschwinge> braunr: http://www.gnu.org/software/hurd/news/2010-01-31.html + <teythoon> it raises an important point btw, the authentication done by + processes on the Hurd is one sided, only the client authenticates at the + server + <braunr> yes + <tschwinge> It'S also mentioned in + http://www.gnu.org/software/hurd/hurd/documentation.html -- but of + course, any results he got from his work really should be integrated more + properly into the existing body of documents. + <tschwinge> As with so many other documents/discussions/etc. ;-| diff --git a/hurd/libstore/part.mdwn b/hurd/libstore/part.mdwn index 5260d05d..29ef9072 100644 --- a/hurd/libstore/part.mdwn +++ b/hurd/libstore/part.mdwn @@ -1,4 +1,5 @@ -[[!meta copyright="Copyright © 2010, 2012 Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2010, 2012, 2013 Free Software Foundation, +Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this @@ -28,6 +29,132 @@ A similar problem is described in [[community/gsoc/project_ideas/unionfs_boot]], and needs to be implemented. -# TODO +# Open Issues -How to use, etc. +## Documentation + +[[!tag open_issue_documentation]] + +## [[open_issues/hurd_build_without_parted]] + +## IRC, freenode, #hurd. 2013-09-21 + + <phcoder> Hello, guys. Is there a way to know where partition starts on + hurd. E.g. given hd0s1 get "2048 sectors" + <youpi> yes, it's the storeinfo RPC + <youpi> let me find you a pointer + <phcoder> in GRUB 2 files for determining device relations are a mess of + #if's. I try to split it into logical files and make common logic + uniform. Current Hurd's logic is completely different and, actually, + wrong. Same logic is used by Mac OS X part ... + <youpi> phcoder: Mmm, I guess you never got the userland-part.patch + upstream + <youpi> ah, yes ,you did + <youpi> I mean the find_hurd_root_device function + <youpi> grub was previously using file_get_storage_info + <phcoder> youpi: find_hurd_root_Device/file_get_storage info is about + translating / -> /dev/hd0s1. Current problem is in step hd0s1 -> + hd0,msdos1 + <youpi> yes, but iirc file_get_storage_info might work for hd0s1 itself + <phcoder> I see, let me try this + <phcoder> youpi: file_get_storage gives offset=0 size=partition size + <youpi> (file_get_storage) damn + <phcoder> and name=hd0s1 + <youpi> ah, that might be because we're still using in-kernel partition + table, instead of the parted partition table + <phcoder> looks like file_get_storage would be useful to get block size + though + <phcoder> youpi: is parted already used in some cases? Any reliable way to + check for it? Any way to access kernel partition map? Ioctl? RPC to + kernel? + <youpi> the parted table is only enabled in the debian installer for + now. You can set up one for yourself by running e.g. settrans -c + /tmp/myhd0s1 /hurd/storeio -T typed part:1:device:hd0 + <youpi> I don't think there is any ioctl/RPC to get the kernel partition + table + <phcoder> youpi: is it using Linux partition code with some glue? + <youpi> phcoder: the kernel partition table, yes + <phcoder> youpi: that's bad. it's probably one of the least consistent + numbering schemes. It would imply that it only worked because only + simplest cases were ever tested + <youpi> I know + <youpi> that's why we want to migrate to the parted-based partition table + support + <youpi> (which also brings us much better support than the old linux2.0 + code :) ) + <phcoder> youpi: I've looked into code and must say that I dislike what I + see: partitions handled in ide/ahci/sd/... + <youpi> phcoder: which code? + <phcoder> youpi: gnumach + <youpi> sure, that's not what we want in the end + <phcoder> grep -r start_sect + <youpi> it's just the legacy linux way of doing partition support + <phcoder> Well Linux at least gives a meaningful ioctl + <phcoder> couldn't find any hint of it in gnumach + <youpi> we didn't bother to add one since the parted way is supposed to be + what we have in the end + <phcoder> youpi: I can't make our code follow sth that might be the case in + the future + <youpi> why not? + <youpi> that's the way we will go + <youpi> it's not just hypothetic + <youpi> we just can't continue maintaining disk drivers in the kernel + <youpi> so it won't be in the kernel + <phcoder> youpi: if I do then GRUB won't work on current GNU/Hurd anymore + <youpi> can't you also keep the old code? + <youpi> as a fallback when the proper way does not work (yet) + <phcoder> More hairs... :( + <phcoder> How do I check for it? offset == 0 isn't proper as partitions may + start at 0 + <phcoder> but checking than name still refers to partition is probably the + right way + <youpi> I don't see what you mean + <youpi> (about name) + <phcoder> youpi: I mean that we need a way to know that current code is + used and not future parted-based code + <youpi> phcoder: I understand that for the offset ==0 thing + <youpi> but I didn't understand the phrase you wrote just after that + <phcoder> youpi: file_get_storage gives back a name. If this name is the + same as the partition we requested in the first place then it's current + code + <youpi> ah, ok + <youpi> yes, if the name is the same, it means it's not actually a + partition + <phcoder> youpi: current gnumach code makes fake devices out of partitions + <youpi> yes + <phcoder> youpi: with settrans command you told, I get num_ints = 0 + <youpi> phcoder: odd, I do get information, e.g.: + <youpi> hurd:/tmp# settrans -c /tmp/mysd0s1 /hurd/storeio -T typed + part:1:device:sd0 + <youpi> hurd:/tmp# storeinfo mysd0s1 + <youpi> device (0x200): sd0: 512: 83905: 42959360: 63+83905 + <phcoder> storeinfo: myhd0s1: Operation not supported + <youpi> do you actually have an hd0 device? + <phcoder> yes + <phcoder> youpi: I typed parted instead of part + <phcoder> Now it works + <youpi> good :) + <phcoder> youpi: what is expected timeline on migration to part interface? + <youpi> there's no real timeline + <youpi> like everything, it'll happen when somebody actually looks at how + to achieve it + <youpi> perhaps it'll be easy, perhaps not. IIRC there is still an issue + with the swapper + <phcoder> youpi: sounds like we're stuck will fallback code for at least + couple of years + <youpi> possibly, entirely depends on people taking the task + <youpi> if that becomes really pressing at some point, I'll have to do it, + but of course, I can not magically do everything in a glimpse + <phcoder> youpi: it's not pressing but just be aware that unusual + partitioning is likely to fail. Probably not huge issue. As to its place + in our code it's not ideal but it's not the only case of suboptimal + construction for specific systems (what we had to do because of Linux + caching is terrifying). I'm not going to make hurd code a scapegot of + more generic problem + <phcoder> youpi: and since we very rarely drop support this code is + probably stuck for good + <youpi> as long as it's not used whenever we get to move to parted-based + partitioning, it's not too bad + <phcoder> youpi: and Mac OS X/Darwin case is even worse. Apparently they + deprecated their *BSD functions (which probably don't work since they + don't use BSD labels) without giving any replacement. diff --git a/hurd/running.mdwn b/hurd/running.mdwn index 41855433..15ee25d9 100644 --- a/hurd/running.mdwn +++ b/hurd/running.mdwn @@ -1,4 +1,4 @@ -[[!meta copyright="Copyright © 2007, 2008, 2009, 2011, 2012 Free Software +[[!meta copyright="Copyright © 2007, 2008, 2009, 2011, 2012, 2013 Free Software Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable @@ -17,6 +17,7 @@ There are several different ways to run a GNU/Hurd system: * [[microkernel/mach/gnumach/ports/Xen]] - In Xen * [[Live_CD]] * [[QEMU]] - In QEMU +* [[openstack]] - In openstack * [[chroots|chroot]] need a couple of tricks to work properly. * [[VirtualBox]] - In VirtualBox * [[vmware]] (**non-free!**) diff --git a/hurd/running/debian/dhcp.mdwn b/hurd/running/debian/dhcp.mdwn index afa46799..849ff382 100644 --- a/hurd/running/debian/dhcp.mdwn +++ b/hurd/running/debian/dhcp.mdwn @@ -1,4 +1,5 @@ -[[!meta copyright="Copyright © 2011, 2012 Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2011, 2012, 2013 Free Software Foundation, +Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this @@ -29,3 +30,97 @@ scripts, but has its own `/libexec/rc` script -- which integrates scripts from * [[!debbug 616290]] * [[Proper Hurdy DHCP support|hurd/translator/pfinet/dhcp]] + + * [[!message-id desc="dhclient aborting with a stack smashing error" + "874ngfvwn4.fsf@kepler.schwinge.homeip.net"]] + + IRC, freenode, #hurd, 2013-08-21: + + <teythoon> yay, I fixed the path of the dhcp leases file... + <teythoon> ... and now dhclient dies of a buffer overflow + <teythoon> fortunately the fix is rather simple, anyone who cares about + the security of his box just has to stop using isc software + <teythoon> the code is full of stuff like char foo[100]; /* surely + that's enough */ + <pinotree> note that our version of isc-dchp (the one in ports) is + older than the latest one available in unstable (which is still older + than the latest upstream releases) + <teythoon> so? + <pinotree> dunno, might have been fixed or not + <teythoon> ^^ yeah sure + <gnu_srs> A lot of software has these limitations and PATH_MAX, + MAXPATHLEN issues :( + <pinotree> having a limitation is not a problem per-se + <teythoon> no, only software written in c has these kind of problems + <pinotree> the problem is not checking whether the limits are hit + <teythoon> well, looking at the source of isc-dhcp my time is better + spent making another dhcp client work on hurd + <teythoon> also reading up on bug #616290 does make me want to avoid + touching it ever + <braunr> hehe + <gnu_srs> teythoon: somebody was offering an alternative to the isc + dhcpclient, but I think it was rejected by Samuel? + <teythoon> why would he do that? + <braunr> probably for compliance + <gnu_srs> He probably thought they would release a new version soon, is + 4.3.0 out yet? + <teythoon> well, as soon as my fixes for ifupdown go in, dhclient will + start crashing + <teythoon> no, there is no new version released + <teythoon> no major one that is + <teythoon> 4.2.5 is out + <gnu_srs> can't you just increase the buffer size, where is the problem + exactly? + <teythoon> I have no idea + <gnu_srs> The Hurd patches are not in 4.2.5, they were promised for + 4.3.0a1. + <gnu_srs> Still the buffer overflow problem might be present in 4.2.5 + if patched to build on Hurd. + <braunr> there, darnassus now has a fully featured git/gitweb service + <teythoon> :) + <teythoon> btw, I managed to reproduce the crash reliably + <teythoon> rm /var/lib/dhcp/*; dhclient -v /dev/eth0 ... *boom* + <teythoon> ditch the -v, everything works, and now that there is a + lease file, you can add the -v again and it works + <braunr> ew :) + <teythoon> and what has dhclient.c to say for its defense? + <teythoon> log_info("%s", ""); + <teythoon> hm, not much :/ + + IRC, freenode, #hurd, 2013-08-22: + + <teythoon> uh, the isc-dhcp situation is a huge pita, the source on + -ports does not compile anymore :/ + + IRC, freenode, #hurd, 2013-08-23: + + <gnu_srs> teythoon: Was it the slash in the network interface names + that caused the buffer overflow in dhclient? + <teythoon> gnu_srs: no, previously no dhcp leases file was written and + everything was fine + <pinotree> teythoon: did you really develop your patch against that old + version of ifupdown? + <teythoon> gnu_srs: now it is written, and for some reason dhclient + crashes *iff* -v is given *and* there is no previous lease file + <teythoon> pinotree: no, I did not. that was only reportbug including + information from my desktop machine without asking me + <teythoon> but when I first looked at ifupdown it was still a 6000 + lines noweb file >,< + <teythoon> that was fun + <pinotree> which version is it against? + <teythoon> hg tip + + IRC, freenode, #hurd, 2013-08-30: + + <tschwinge> teythoon: I understand correctly that you found that + id:"874ngfvwn4.fsf@kepler.schwinge.homeip.net" in fact was really + "just" a buffer overflow in the dhclient code? + <teythoon> tschwinge: ah, most interesting, I didn't realize that you + stumbled across this as well + <teythoon> to be honest I don't know what's going on there, I only + observed what I wrote in my report + <teythoon> for me it started crashing once the lease file was actually + a valid path (i.e. not to a non-existing directory b/c of the slashes + in /dev/eth0) + <teythoon> I tried to rebuild the package served on debian-ports, but + that failed diff --git a/hurd/running/openstack.mdwn b/hurd/running/openstack.mdwn new file mode 100644 index 00000000..af03583b --- /dev/null +++ b/hurd/running/openstack.mdwn @@ -0,0 +1,14 @@ +[[!meta copyright="Copyright © 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, +2013 Free Software Foundation, Inc."]] + +[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable +id="license" text="Permission is granted to copy, distribute and/or modify this +document under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no Invariant +Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] + +One can tell openstack to avoid using virtio drivers, and use emulated hardware instead: + + glance image-create --property hw_disk_bus=ide --property hw_cdrom_bus=ide --property hw_vif_model=rtl8139 --disk-format raw --container-format bare --name gnu-hurd --copy-from http://people.debian.org/~sthibault/hurd-i386/debian-hurd.img diff --git a/hurd/running/requirementsforlivecd.mdwn b/hurd/running/requirementsforlivecd.mdwn deleted file mode 100644 index 858988d1..00000000 --- a/hurd/running/requirementsforlivecd.mdwn +++ /dev/null @@ -1,24 +0,0 @@ -[[!meta copyright="Copyright © 2013 Free Software Foundation, Inc."]] - -[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable -id="license" text="Permission is granted to copy, distribute and/or modify this -document under the terms of the GNU Free Documentation License, Version 1.2 or -any later version published by the Free Software Foundation; with no Invariant -Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license -is included in the section entitled [[GNU Free Documentation -License|/fdl]]."]]"""]] - -HERE STARTS YOUR NEW CONTENT -- remove everything from here on, including this -line. - -By creating this page, you agree to assign copyright for your contribution to -the Free Software Foundation, <http://www.fsf.org/>. The Free Software -Foundation promises to always use a free documentation license (as per our -criteria of free documentation) when publishing your contribution. We grant -you back all your rights under copyright, including the rights to copy, modify, -and redistribute your contributions. - -We're requiring these copyright assignments, so that we'll easily be able to -include your contributions in official GNU documentation, such as the GNU Hurd -Reference Manual, etc. Send email to <hurd-maintainers@gnu.org> if there are -questions. diff --git a/hurd/subhurd.mdwn b/hurd/subhurd.mdwn index af119af3..55927fdd 100644 --- a/hurd/subhurd.mdwn +++ b/hurd/subhurd.mdwn @@ -1,5 +1,5 @@ -[[!meta copyright="Copyright © 2007, 2008, 2010, 2011 Free Software Foundation, -Inc."]] +[[!meta copyright="Copyright © 2007, 2008, 2010, 2011, 2013 Free Software +Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this @@ -42,6 +42,22 @@ set up another Hurd on a different partition, without ever rebooting. (You can run the `native-install` step from a chroot or already in a subhurd.) +### IRC, freenode, #hurd, 2013-09-15 + + <gnu_srs> Never dared to try a subhurd, any link to the howto? + <teythoon> gnu_srs: I followed + http://www.gnu.org/software/hurd/hurd/subhurd.html though using crosshurd + didn't work for me, I just used debootstrap + <teythoon> gnu_srs: and you need a separate filesystem translator (i.e. not + /) for that + <teythoon> the easiest way is to add another virtual disk to you qemu setup + <braunr> use the qemu image directly + <braunr> simplest way to set up a subhurd + <braunr> just change fstab from the host before the first boot to avoid + making the subhurd use the same hd0 drive as the host + <teythoon> braunr: nice idea :) + + ## Booting To boot the subhurd, you need a boot script. For historical reasons, usually @@ -86,7 +102,8 @@ it! practice [that doesn't work at the moment](http://savannah.gnu.org/bugs/?17341).) -You can provide the subhurd with a network card by passing a -f option to `boot`. +You can provide the subhurd with a network card by passing a `-f` option to +`boot`. Now the subhurd should boot just like a normal Hurd started directly from GRUB, finally presenting a login prompt. The `boot` program serves as proxy for the @@ -120,6 +137,362 @@ look at the number of threads (e.g. using `ps -l`), as many servers have very characteristic thread counts. +### IRC, freenode, #hurd, 2013-08-09 + + <teythoon> btw, is there a way to get dde-based networking into a subhurd? + <teythoon> the wiki instructions look like they're for the mach driver + <teythoon> and starting the dde translator inside the subhurd does not work + for me + <teythoon> that's probably a good thing though + <youpi> the netdde process will need privileged access to mach + <youpi> for hardware access + <braunr> you can't easily use netdde from a subhurd, unless with a + different nic + <braunr> i usually rebuild mach with in kernel devices so both the main and + subhurd can share on nic + <braunr> one* + <youpi> could a port to netdde perhaps forwarded to the subhurd? + <braunr> zengh da wrote the eth-multiplexer for that iirc + <youpi> it's a matter of making it appear as an eth0 device on the master + port aiui + <braunr> zheng* + <teythoon> yes, I looked at that + <teythoon> what is the master port? + <youpi> on a plain hurd system it's the port that privileged processes can + use to access mach devices + <youpi> in a subhurd, it's the same for the subhurd, to access some devices + that you choose to give access to + <braunr> its real name is the "device master port" + <teythoon> ah yes + + +#### IRC, freenode, #hurd, 2013-08-10 + + <antrik> teythoon: use eth-multiplexer to use the NIC within a + subhurd. that's exactly what it was created for. + <antrik> I don't remember whether it's even possible to share a "raw" + netdde device... I don't think I ever tried that; and I don't remember + enough of the theory to tell whether it should be possible + <antrik> but I really don't see the reason to, when eth-multiplexer is + available + <antrik> (IMHO running an eth-multiplexer on top of netdde should be the + default setup in fact) + <antrik> as for actually passing on the device, that should be perfectly + possible with zhengda's modified subhurd... but I don't remember whether + that was ever merged upstream + <antrik> (you will definitely need that for using netdde in a subhurd, + regardless whether through eth-multiplexer or directly) + + +#### IRC, freenode, #hurd, 2013-09-15 + + <teythoon> I wonder if we can modify the boot program so that it passes + ports from the mother hurd to the subhurd + <teythoon> so that we could pass in a port to the eth-multiplexer + <teythoon> or use like /hurd/remap as the root translator for the subhurd + <braunr> eth-multiplexer was created exactly for that iirc, + <braunr> so it's probably already done somewhere + + +#### IRC, freenode, #hurd, 2013-09-16 + + <gnu_srs> braunr: regarding subhurd did you mean to install + sthibault/hurd-i386/debian-hurd.img.tar.gz + <gnu_srs> on a separate partition and booting using the instructions for + subhurds on the web. + <braunr> gnu_srs: yes + <braunr> be careful that the subhurd doesn't use the same partition as the + main hurd, that's all + <gnu_srs> what about changing fstab? + <braunr> 12:17 < braunr> be careful that the subhurd doesn't use the same + partition as the main hurd, that's all + <teythoon> gnu_srs: yes, you need to change the fstab + <teythoon> currently it is used for fscking stuff, so if it points to your + main partition it will cause severe corruption + <teythoon> gnu_srs: you also have to specify the right partition in the + servers.boot file + <gnu_srs> fstab of the subhurd image? + <teythoon> yes + <gnu_srs> how to unpack the .img file (just to be sure)? + <teythoon> gnu_srs: you don't need to, just use the img file as secondary + hard disk image + <gnu_srs> Then how should I be able to change fstab of the image? + <teythoon> boot your hurd box, mount the partition and change it + <gnu_srs> I missed something here: on my partition /my_chroot I have have + the file debian-hurd-20130504.img + <teythoon> gnu_srs: ah, you copied it to the partition, braunr meant to use + it as the secondary disk, e.g. qemu ... -hdb debian-hurd-20130504.img ... + <gnu_srs> That is the same as installing another cd image, where does the + subhurd come into play? + <teythoon> mount the partition on the secondary hd, fix the fstab there, + mount it r/o, get the servers.boot file from the wiki, modify it so that + it points to the right partition, execute boot servers.boot /dev/<your + partition>, probably /dev/hd1s1 + <gnu_srs> BTW: unpacking was problematic: tar: debian-hurd-20130504.img: + Cannot seek to 2147696640 (2G limitations) + <teythoon> I wonder why you did this on your hurd system in the first + place... + <gnu_srs> I thought I could use that partition, /my_chroot as a chroot + place. So it won't work for subhurds? + <teythoon> well, there are several ways to setup a subhurd. one is to + already have a spare partition for that and use crosshurd or as I did + debootstrap to install a debian system there + <teythoon> braunr suggested an even easier way, download the .img file and + use it as secondary hard disk + <teythoon> you ended up doing kind of both + <gnu_srs> I tried once with debootstrap and that created a disaster... + <teythoon> how so? + <gnu_srs> The install errored out, and the whole filesystem (including /) + was left in a broken state. Maybe I tried + <gnu_srs> that without using a separate partition. Don't remember any + longer. So you say it's safe now? + <teythoon> I used it successfully to setup my subhurd + <gnu_srs> and you have your subhurd in a separate partition, installed from + there too, as root? + <gnu_srs> the web page only mentions crosshurd, and that failed for you? + <teythoon> yes, having a separate partition is (currently) necessary to run + a subhurd + <teythoon> yes, I used debootstrap as root, afaics that is necessary + <teythoon> and yes, as I said the other day, I tried crosshurd first and it + failed + <teythoon> then again, I fail to see any reason to use crosshurd these days + <teythoon> it's only a wrapper around debootstrap anyway, using it with + --foreign and fixing up stuff later + <teythoon> one has more control over the process if one uses debootstrap + directly + <gnu_srs> I still don't dare to do it yet. I'll create another image using + netinst with a separate partition and try out first. + <gnu_srs> When installing a new image using netinst.iso (2013-06-30) and + rebooting /proc does not get mounted? + <teythoon> gnu_srs: is that a statement or a question? + <gnu_srs> A statement. + <teythoon> it's not customary to end statements with question marks ;) + <gnu_srs> s/mounted?/mounted, why?/ + <teythoon> well, you seem to be the last person to perform such an + installation, so you are in the perfect position to answer this question. + <gnu_srs> cat /var/log/dmesg? + <gnu_srs> On other images I have: fsysopts /proc; /hurd/procfs + --clk-tck=100 --stat-mode=444 --fake-self=1 + <youpi> gnu_srs: no, check the installation log + <youpi> gnu_srs: and what does showtrans say? + <gnu_srs> showtrans /proc; <empty> + <gnu_srs> which log file to look for? + <youpi> the installation log, somewhere in /var/log probably + <gnu_srs> I only find /proc in /var/log/installer/syslog, mainly printing + out errors not finding /proc/mounts + <youpi> iirc the /proc translator should be set during the hurd package + configuration + <youpi> you should probably look for that part in the log + <youpi> Setting up translators: /hurd/exec /hurd/proxy-defpager + /hurd/pflocal (+link) /hurd/pfinet (+link) (+link) /hurd/procfs -c + /hurd/password crash-kill crash-suspend crash-dump-core crash. + <youpi> that part + <gnu_srs> debootstrap: /hurd/procfs -c and in-target: /hurd/procfs -c No + errors + <youpi> I don't understand what that means + <youpi> please explain in more details + <gnu_srs> see: http://paste.debian.net/41195/ + <youpi> makes much more sense :) + <gnu_srs> Where is the 'Setting up translators' done? I cannot find + anything in /var/lib/dpkg/info/hurd* or /etc/init.d/... + <pinotree> /usr/lib/hurd/setup-translators, called in hurd.postinst + <gnu_srs> tks:) + <gnu_srs> Hi, when installing a new image with debootstrap to /chroot the + script boot/servers.boot is already there (as well as in /boot/ + grub) + <gnu_srs> Is it OK to use that file to boot the subhurd? + <gnu_srs> using /boot/servers.boot or /chroot/boot/servers.boot (if the + /chroot partition is unmounted it cannot be used?) + <gnu_srs> and how to unmount /chroot: umount does not work? + <gnu_srs> braunr: I'm also trying to find out what's wrong with glibc, when + my subhurd is up and running 2.13-39 (if possible) + <gnu_srs> I know I should issue settrans command, but I'm not yet fluent in + translators. + <gnu_srs> sorry:-/ + <gnu_srs> Now this, after a reboot: unknown code P 30 while trying to open + /dev/hd0s3 (/chroot) + <gnu_srs> Disk write protected: use the -n option to do a read-only check + of the device. + <gnu_srs> fsysopts /dev/&hd0s1 --writable: Operation not supported?? + <gnu_srs> OK, I'm giving up for now, no subhurd:-( and a broken install. + <gnu_srs> Which terminal to use in rescue mode, TERM is not set, + dumb,mach,hurd does not work with nano? + <gnu_srs> e2fsck /dev/ho0s3; e2fsck: Unknown code P 2 while trying to open + /dev/ho0s3; Possibly non-existent device? + <gnu_srs> mke2fs /dev/hd0s3; /dev/hd0s3 is not a block special device.; + Proceed anyway? (y,n) n: What's going on (hd0s3 not mounted)?? + <gnu_srs> anybody, help? + <gnu_srs> after removing and creating the partition again:mke2fs + /dev/hd0s3, <same>, mke2fs: Unknown code P 13 while trying to determine + filesystem size: What's going on? + <gnu_srs> Where to find the glibc-2.13 versions which used to be at + debian-ports?. + <gnu_srs> seems they can be found on snapshot.debian.org + + +#### IRC, freenode, #hurd, 2013-09-17 + + <gnu_srs> teythoon: Installing subhurd via debootstrap on partition + /chroot fails miserably. Install hangs, and after reboot \rm -r + /chroot/* fails for dev and proc + <gnu_srs> Are there translators running there already? I have not + booted the subhurd. + <gnu_srs> translators for hd0s3 (/chroot) are storeio and + ex2fs.static. Do I have to stop them to be able to clean out + /chroot? + <gnu_srs> mount -v /chroot; settrans -a /chroot /hurd/ext2fs + /dev/hd0s3; + <gnu_srs> ext2fs: /dev/hd0s3: panic: main: device too small for + superblock (0 bytes); + <gnu_srs> mount: cannot start translator /hurd/ext2fs: Translator + died + <gnu_srs> Please, somebody! + <gnu_srs> don't ask to ask, just ask, right? + <braunr> we've already told you everything you need + <braunr> just get it right + <braunr> for example, i told you to be careful about fstab so that + the subhurd wouldn't use the main hurd partition + <braunr> but you managed to screw that + <braunr> good job + <gnu_srs> I installed the subhurd in a partition /chroot /dev/hd0s3 + using debootstrap + <braunr> i don't know deboostrap, it may be broken, use the disk + image youpi maintains + <gnu_srs> ant the install screwed up with debootstrap + <gnu_srs> ok; then I cannot use a partition, but another disk in + kvm, e.g. hdb? + <braunr> gnu_srs: hd1 + <gnu_srs> something is fishy with glibc, definitely, that's why I'm + trying to set up a subhurd to revert to 2.13-39 + <gnu_srs> hi, when trying to boot a subhurd: /hurd/ext2fs.static: + hd0s3: Gratuitous error; bye + <braunr> gnu_srs: why hd0s3 ? + <braunr> it should be hd1s1 + <gnu_srs> I'm still using a separate partition /my_chroot + /hd0s3. Will switch to hd1 next. teythoon? + <gnu_srs> the servers.boot script use absolute + paths:/hurd/ext2fs.static and /lib/ld.so.1 /hurd/exec, + <gnu_srs> shouldn't they be relative to /my_chroot? + <braunr> no + <braunr> they're actually from your host + <gnu_srs> teythoon: please, how did you succeed to boot a subhurd + in a partition? + <gnu_srs> using debootstrap + <teythoon> gnu_srs: from my shell history: + <teythoon> : 1374672426:0;debootstrap sid /mnt + http://http.debian.net/debian/ + <teythoon> : 1374673020:0;cp /etc/hosts /etc/resolv.conf /mnt/etc + <teythoon> : 1374673048:0;cp /etc/passwd /etc/shadow /mnt/etc + <braunr> teythoon: so it does work fine ? + <braunr> great + <teythoon> yes, why wouldn't it? + <teythoon> gnu_srs: I then remounted that partition r/o and used + the servers.boot file from the wiki to boot it + <teythoon> braunr: why wouldn't it? (you do mean the debootstrap + part, don't you?) + <braunr> teythoon: i don't know + <braunr> i've heard it wasn't maintained any more + <braunr> not being maintained is a good reason for something to + become unusable/untrustable with time + <teythoon> o_O it is at the heart of d-i, isn't it? + <teythoon> I actually do most Debian installations using + debootstrap directly + <braunr> ah + <braunr> ok :) + <braunr> teythoon: even hurd ones ? + <teythoon> braunr: well, just the subhurd installation, but that + went as expected + <braunr> good + <gnu_srs> Finally: I found the reason for Gratuitous error, I used + the /boot/servers.boot script, + <gnu_srs> that being different to the one on the wiki:-/ + <gnu_srs> Is it possible to copy files between a host hurd and + subhurd, what about access to eth0? + <gnu_srs> Hi, when starting the subhurd I see some warnings/error: + http://paste.debian.net/41963/ + <gnu_srs> 1) A spelling error execunable-> executable + <gnu_srs> 2) libports: invalid destination port + <gnu_srs> 3) mach-defpager: another already running + <pinotree> "execunable" is not a typo, but just "exec" and "unable + ..." without a space-type character + <gnu_srs> OK, sounds more plausible + <gnu_srs> Ah, the printouts are mixed, no bug + <gnu_srs> When setting up nework in the subhurd: /hurd/pfinet: + file_name_lookup /dev/eth0: Translator died + <gnu_srs> /hurd/pfinet: device_open(/dev/eth0): (os/device) no such + device + <gnu_srs> settrans: /hurd/pfinet: Translator died + + +#### IRC, freenode, #hurd, 2013-09-18 + + <youpi> priority does not matter much + <youpi> memory manager is not really surprising, there's indeed already one + <youpi> what is actually the problem? + <gnu_srs> So these are merely warnings? + <youpi> gnu_srs: yes + <gnu_srs> Real problems are I cannot set up networking, e.g. wget ...: + Connecting to ... failed: Address family not supported by protocol. + <youpi> gnu_srs: did you give the subhurd a network card? + <gnu_srs> How? + <gnu_srs> and do I need to set up fstab, for now it's empty. + <gnu_srs> I just installed the base with dbootstrap + <youpi> gnu_srs: -f option of boot + <youpi> e2fsck will need fstab for sure + <youpi> otherwise it can't divine what should be checked + <gnu_srs> Why is the /boot/servers.boot different from the subhurd one on + the wiki? Is it used at all, I thought grub was in charge. + <youpi> it's not used at all + <gnu_srs> maybe better to put in the subhurd one there then, with a + comment? + <youpi> no, since /boot/servers.boot is supposed to be used for machine + boot + <youpi> not subhurd boot + <gnu_srs> what about putting a copy of the suhurd one there, with a + different name? + <youpi> probably a good idea, yes + <youpi> matter of making it happen + <gnu_srs> the wiki page on subhurd does not say how to set up networking, + only that you can do it. + <youpi> matter of adding the information + <youpi> I remember it's the -f option of boot + <youpi> make it work, and add the information for others + <gnu_srs> I could try, but don't know how to add a network card to the + subhurd, and e.g. how to set up swap + <youpi> see -f option + <gnu_srs> of boot? + <youpi> "gnu_srs: -f option of boot" + <youpi> if you could read what we write, that'd make things happen way + faster + <gnu_srs> yes I saw your comment above, it was just to be 100% sure:-D + <gnu_srs> device_file=/dev/eth0 or something else? + <gnu_srs> eth0 is used by the host already + <youpi> did you read boot --help ? + <youpi> iirc it's not a problem, both will receive all frames + <gnu_srs> yes I did + <youpi> then I don't see where you took device_file from + <youpi> at least in that form + <youpi> --device=device_name=device_file + <youpi> that means rather something like --device=foo=bar + <gnu_srs> so -f /dev/eth0 is correct usage then? + <youpi> didn't you see that in what I wrote, there was a "=" in there? + <gnu_srs> -f is the short option, --device is the long, I don't see the + need for = in the short option? + <youpi> in the long option there are *two* = + <gnu_srs> yes, but in the short no? + <youpi> why not? + <youpi> long -> short usually drops one = + <gnu_srs> to summarize: -f=/dev/eth0 or --device=eth_sub=/dev/eth0? + <youpi> why shouldn't there be a eth_sub in the short version? + <gnu_srs> 10:15:49) youpi: long -> short usually drops one = + <youpi> yes, it drops the = + <youpi> but nothing else + <youpi> if the long option needs some information, the short needs it too? + <youpi> -? + <gnu_srs> correct now? -f eth_sub=/dev/eth0 or --device=eth_sub=/dev/eth0? + <youpi> yes + <gnu_srs> k! + + # Further Info Read about using a subhurd for [[debugging_purposes|debugging/subhurd]]. diff --git a/hurd/subhurd/discussion.mdwn b/hurd/subhurd/discussion.mdwn index 6e694677..fac93625 100644 --- a/hurd/subhurd/discussion.mdwn +++ b/hurd/subhurd/discussion.mdwn @@ -170,3 +170,13 @@ License|/fdl]]."]]"""]] <zacts> ah ok <braunr> in theory, subhurds can run without root privileges <braunr> (but there are currently a few things that prevent it) + + +## IRC, freenode, #hurd, 2011-06-07 + + <zacts> would hurd jails be more powerful than FreeBSD jails? how so? + <braunr> not more powerful + <braunr> easier to develop + <braunr> safer + <braunr> perhaps more powerful too, but that entirely depends on the + features you want inside diff --git a/hurd/translator.mdwn b/hurd/translator.mdwn index f1c07bde..52cd09f7 100644 --- a/hurd/translator.mdwn +++ b/hurd/translator.mdwn @@ -90,18 +90,22 @@ The [[concept|concepts]] of translators creates its own problems, too: * [[hello]] * [[auth]] * [[exec]] +* [[proc]] * [[pfinet]] +* [[eth-filter]] * [[pflocal]] * [[hostmux]] * [[storeio]] * [[ext2fs]] * [[fatfs]] +* [[ufs]] * [[magic]] * [[mtab]] * [[unionfs]] * [[nfs]] * [[symlink]] * [[firmlink]] +* [[fifo]] * ... @@ -113,6 +117,7 @@ The [[concept|concepts]] of translators creates its own problems, too: * [[procfs]] * [[nsmux]] * [[netio]] +* [[socketio]] * [[tarfs]] * [[gopherfs]] * [[smbfs]] @@ -123,7 +128,7 @@ The [[concept|concepts]] of translators creates its own problems, too: *These Translators are available in the [hurdextras repository](http://savannah.nongnu.org/cvs/?group=hurdextras) but not yet described on this website. They are in varying stages of Development.* * [jfs](http://www.nongnu.org/hurdextras/#jfs) -* [httpfs](http://www.nongnu.org/hurdextras/#httpfs) +* [[httpfs]] * [memfs](http://www.nongnu.org/hurdextras/#memfs) * [notice](http://www.nongnu.org/hurdextras/#notice) * [pith](http://www.nongnu.org/hurdextras/#pith) diff --git a/hurd/translator/auth.mdwn b/hurd/translator/auth.mdwn index d9e70ec2..7fd4832c 100644 --- a/hurd/translator/auth.mdwn +++ b/hurd/translator/auth.mdwn @@ -1,12 +1,19 @@ -[[!meta copyright="Copyright © 2008 Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2008, 2013 Free Software Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license -is included in the section entitled -[[GNU Free Documentation License|/fdl]]."]]"""]] +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] + +The *auth server* (or, *authentification server*). + +It is stated by `/hurd/init`. + + +# Documentation [[*The_Authentication_Server*|documentation/auth]], the transcript of a talk about the details of the authentication mechanisms in the Hurd by Wolfgang diff --git a/hurd/translator/eth-filter.mdwn b/hurd/translator/eth-filter.mdwn index 36ef4217..b5dc8f8f 100644 --- a/hurd/translator/eth-filter.mdwn +++ b/hurd/translator/eth-filter.mdwn @@ -8,20 +8,45 @@ Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled [[GNU Free Documentation License|/fdl]]."]]"""]] -`eth-filter` is a translator that implements a very simple stateless firewal. +`eth-filter` is a translator that implements a very simple stateless firewall. + # Source [[source_repositories/incubator]], dde -# Usage: + +# Usage For instance, to drop any attempt to access port 22: - settrans -c /dev/eth0f /hurd/eth-filter -i /dev/eth0 -r "not port 22" + # settrans -c /dev/eth0f /hurd/eth-filter -i /dev/eth0 -r "not port 22" + +This creates a `/dev/eth0f` device, which is the filtered version of +`/dev/eth0`. One can then use `/dev/eth0f` instead of `/dev/eth0`: + + # settrans /servers/socket/2 /hurd/pfinet -i /dev/eth0f [...] + +..., or run `dhclient /dev/eth0f`, or similar. + +See also Zheng Da's [[user/zhengda/howto]]. + + +# Open Issues -This creates a /dev/eth0f device, which is the filtered version of /dev/eth0. One can then configure network by hand using /dev/eth0f instead of /dev/eth0: +## IRC, freenode, #hurd, 2013-07-27 - settrans /servers/socket/2 /hurd/pfinet -i /dev/eth0f ... +[[!tag open_issue_hurd]] -or run dhclient /dev/eth0f, etc. + <youpi> ok, so as usual we actually *already* have a firewall + <youpi> it's the eth-filter translator from zheng da + <youpi> it has just never been really pushed forward... + <teythoon> good news :) + <youpi> well, the bad news is that it probably doesn't support connection + tracking + <youpi> since it's just bpf + <youpi> using the libpcap syntax + <teythoon> well, a stateless fw should do for Debian/Hurds needs for now, + right? + <youpi> yes + <youpi> and it does work indeed diff --git a/hurd/translator/examples.mdwn b/hurd/translator/examples.mdwn index 867d4935..4947808e 100644 --- a/hurd/translator/examples.mdwn +++ b/hurd/translator/examples.mdwn @@ -16,7 +16,7 @@ or [hurd-extras](http://www.nongnu.org/hurdextras/). cvs -z3 -d:pserver:anonymous@cvs.savannah.nongnu.org:/sources/hurdextras co <modulename> -* httpfs translator +* [[httpfs]] translator <!-- Prevent ikiwiki / Markdown rendering bug. --> @@ -28,7 +28,7 @@ or $ cd tmp/ $ ls -l -* ftpfs translator +* [[ftpfs]] translator <!-- Prevent ikiwiki / Markdown rendering bug. --> @@ -67,13 +67,13 @@ This is not as fast as `tar czvf newfile.tar.gz all my files`, but at least it's $ settrans -fgca /servers/socket/2 /hurd/pfinet -i <interface> -a <ip address> -m <subnet mask> -g <gateway ip> -* Console translator -- setting up virtual consoles +* [[Console]] translator -- setting up virtual consoles <!-- Prevent ikiwiki / Markdown rendering bug. --> $ console -d vga -d pc_mouse -d pc_kbd -d generic_speaker /dev/vcs -* iso9660fs translator -- 'mounting' your cdrom +* [[iso9660fs]] translator -- 'mounting' your cdrom <!-- Prevent ikiwiki / Markdown rendering bug. --> diff --git a/hurd/translator/exec.mdwn b/hurd/translator/exec.mdwn index 54abba7e..1dc0ea26 100644 --- a/hurd/translator/exec.mdwn +++ b/hurd/translator/exec.mdwn @@ -1,4 +1,5 @@ -[[!meta copyright="Copyright © 2009, 2012 Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2009, 2012, 2013 Free Software Foundation, +Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this @@ -11,4 +12,9 @@ License|/fdl]]."]]"""]] The *exec* server, listening on `/servers/exec`, is responsible for preparing the execution of processes. + +# Open Issues + + * [[open_issues/exec]]. + * [[open_issues/exec_memory_leaks]]. diff --git a/hurd/translator/ext2fs.mdwn b/hurd/translator/ext2fs.mdwn index 20faed5e..e2f6b044 100644 --- a/hurd/translator/ext2fs.mdwn +++ b/hurd/translator/ext2fs.mdwn @@ -179,6 +179,69 @@ small backend stores, like floppy devices. That would be a nice improvement, but only after writeback throttling is implemented. +## Stripped vs. Unstripped `ext2fs.static` + +[[!tag open_issue_hurd]] + + +### IRC, freenode, #hurd, 2013-09-17 + + <teythoon> I always had some trouble with dropping a rebuild ext2fs.static + into my test system and I never figured out why + <teythoon> I just followed a hunch and stripped the binary, and all of the + sudden it works + <teythoon> any ideas why? + <tschwinge> teythoon: I quick search found me: + <https://savannah.gnu.org/bugs/?8497> and + <http://news.gmane.org/find-root.php?message_id=%3c4090243E.2040605%40comcast.net%3e>. + <teythoon> tschwinge: ugh, thanks for the pointers ;) + <tschwinge> teythoon: They won't help too much I fear. Anyway, good + intuition (or whatever) ;-) that you found this out. + <tschwinge> teythoon: Not exactly related to stripped/unstripped per se + (that is, debug information), but in the past we've had an issue about + relro (see binutils/glibc, <http://www.airs.com/blog/archives/189>), + where a variable (that erroneously happend to be in such a read-only + section, if I remember correct) was tried to be modified -- which worked + "sometimes": depending on where exactly it was located in the binary + (which shifted around a page + <tschwinge> boundary by stripped/unstripped), it'd segfault or not. Burnt + several days on that before Samuel (IIRC) eventually figured it out. + <teythoon> tschwinge: well, thanks anyway ;) + + +## Increased Memory Consumption + +### IRC, freenode, #hurd, 2013-09-18 + + <braunr> ext2fs is using a ginormous amount of memory on darnassus since i + last updated the hurd package :/ + <braunr> i wonder if my ext2fs large store patches rework have introduced a + regression + <braunr> the order of magnitude here is around 1.5G virtual space :/ + <braunr> it used to take up to 3 times less before that + <braunr> looks like my patches didn't make it into the latest hurd package + <braunr> teythoon: looks like there definitely is a new leak in ext2fs + <teythoon> :/ + <braunr> memory only + <braunr> the number of ports looks stable relative to file system usage + <teythoon> braunr: I tested my patches on my development machine, it's up + for 14 days (yay libvirt :) and never encountered problems like this + <braunr> i've been building glibc to reach that state + <teythoon> hm, that's a heavy load indeed + <teythoon> could be the file name tracking stuff, I tried to make sure that + everything is freed, but I might have missed something + <braunr> teythoon: simply running htop run shows a slight, regular increase + in physical memory usage in ext2fs + <pinotree> old procfs stikes again? :) + <teythoon> braunr: I see that as well... curious... + <braunr> 16:46 < teythoon> could be the file name tracking stuff, I tried + to make sure that everything is freed, but I might have missed something + <braunr> how knows, maybe completely unrelated + <teythoon> the tracking patch isn't that big, I've gone over it twice today + and it still seems reasonable to me + <braunr> hm + + # Documentation * <http://e2fsprogs.sourceforge.net/ext2.html> diff --git a/hurd/translator/fifo.mdwn b/hurd/translator/fifo.mdwn new file mode 100644 index 00000000..857922fc --- /dev/null +++ b/hurd/translator/fifo.mdwn @@ -0,0 +1,48 @@ +[[!meta copyright="Copyright © 2013 Free Software Foundation, Inc."]] + +[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable +id="license" text="Permission is granted to copy, distribute and/or modify this +document under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no Invariant +Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] + +The *fifo* translator implements named pipes (FIFOs). + + +# Open Issues + +## Not Terminating + +[[!tag open_issue_hurd]] + + +### IRC, OFTC, #debian-hurd, 2013-07-28 + + <gg0> seems fifos started dying, as they should. am i wrong? + <gg0> ( http://bugs.debian.org/629184 ) + <azeem> so you're saying the bug should be closed? + <azeem> best to comment on the bug then + <gg0> i didn't hear anyone working on it, so i'm a bit surprised + <azeem> could be due to lower-level fixes to glibc or so + <gg0> and given often(:|) i'm wrong, i was asking + <pinotree> in two years there have been various changes in glibc and hurd + <pinotree> (for example the switch to pthreads) + <gg0> yeah seems fixed. mknod'ing one then removing it, doesn't leave any + process around + <gg0> cool + <azeem> then please follow-up on the bug and/or close it + <gg0> sure + <gg0> the pleasure of closing it/them is yours + <gg0> great job, whatever you did :) + + +### IRC, OFTC, #debian-hurd, 2013-07-29 + + * gg0 wonders if it can close savannah one as + wellhttps://savannah.gnu.org/bugs/?17128 + <pochu> gg0: wdym? + <pochu> gg0: got an example? + <gg0> http://bugs.debian.org/629184 + <gg0> i didn't close it myself diff --git a/hurd/translator/firmlink.mdwn b/hurd/translator/firmlink.mdwn index 038879db..b53396b0 100644 --- a/hurd/translator/firmlink.mdwn +++ b/hurd/translator/firmlink.mdwn @@ -1,4 +1,4 @@ -[[!meta copyright="Copyright © 2012 Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2012, 2013 Free Software Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this @@ -20,3 +20,15 @@ License|/fdl]]."]]"""]] <braunr> infinity0: firmlinks <infinity0> ah thanks i'll look that up <kilobug> braunr: oh, true, I forgot about that one + + +# Open Issues + + * [[!GNU_Savannah_bug 29809]] + + * IRC, freenode, #hurd, 2013-07-07 + + <youpi> ok, found the firmlink-mv issue + <youpi> will commit that + <pinotree> \o/ + <youpi> (bit of mach_print in translators, took just a few hours) diff --git a/hurd/translator/hostmux.mdwn b/hurd/translator/hostmux.mdwn index 5fab2dc5..ef16505b 100644 --- a/hurd/translator/hostmux.mdwn +++ b/hurd/translator/hostmux.mdwn @@ -29,3 +29,18 @@ When <code>**/ftp**</code> is accessed, the first directory is interpreted as ho You can see the new created translator in the process list: <code>**ps ax | grep ftpsfs**</code> . You shoud see <code>**/hurd/ftpfs / ftp.yourhost.com**</code> . -- [[Main/PatrickStrasser]] - 13 Jul 2004 + + +# Open Issues + +## IRC, freenode, #hurd, 2013-09-21 + +[[!tag open_issue_hurd]] + + <jproulx> ls /http://<ip>:<port>/ + <jproulx> the image came with a global translator though I see it doesn't + grokk the alternate port notation. + <youpi> oh right + <jproulx> I shall return to the fine documentation + <youpi> it's a hostmux, it doesn't understand ports + <youpi> damn, one thus can't url plain urls with that scheme diff --git a/hurd/translator/httpfs.mdwn b/hurd/translator/httpfs.mdwn new file mode 100644 index 00000000..dc4a62f7 --- /dev/null +++ b/hurd/translator/httpfs.mdwn @@ -0,0 +1,100 @@ +[[!meta copyright="Copyright © 2013 Free Software Foundation, Inc."]] + +[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable +id="license" text="Permission is granted to copy, distribute and/or modify this +document under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no Invariant +Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] + +`httpfs` is a virtual filesystem allowing you to access web pages and files. + + +# Source + +<http://www.nongnu.org/hurdextras/#httpfs> + + +# Documentation + +## IRC, freenode, #hurd, 2013-09-03 + +[[!tag open_issue_documentation]] + + <congzhang> hi, why I can't cd to /http:/richtlijn.be/~larstiq/hurd/ to do + <congzhang> grep? + <pinotree> this is not ftp + <congzhang> it works for other file + <pinotree> ? + <congzhang> I can't cd to ~larstiq, I don't know why + <pinotree> http is not a filesystem protocol + <pinotree> while httpfs could try in representing it as such, it is not + something reliable + <congzhang> ok, it's not reliable + <congzhang> I expect it can expose dir like browser + <congzhang> so, the translator just know href from home page, and one by + one + <pinotree> uh? + <congzhang> if ...:80/a/b/c.png exits, but not has a href in homepage, so I + can't cd to a, right? + <pinotree> you are looking things from the wrong point of view + <pinotree> a web server can do anything with URLs, including redirecting, + URL rewriting and whatever else + <congzhang> so, how to understand httpfs's idea? + <congzhang> how httpfs list dir? + <pinotree> check its code + <congzhang> en, no need it's not reliable + <congzhang> it's not work, it's enough + <congzhang> I have an idea, for the file system, we explore dir level by + level, but for http, we change full path one + <congzhang> once time + <congzhang> maybe can allow user to cd any directory, and just mark as some + special color to make user know the translator was not sure, file exist + or not + <congzhang> once the file exits, mark all the parent directory as normal + color? + <rekado> congzhang: you can find more info about httpfs here: + http://nongnu.org/hurdextras/ + <pinotree> congzhang: you're still looking at http from the wrong point of + view + <pinotree> there are no directories nor files + <pinotree> you start a request for a URL, and you get some content back (in + case there's no error) + <congzhang> you mean httpfs just for kidding? + <pinotree> that the content is a web page listing a directory on the + filesystem of the web server machine, or a file sent back via the + connection, or a complex web page, it's the same + <rekado> congzhang: you can only get a list of files if the web server + responds with an index of files + <pinotree> "files" + <rekado> The readme explains how httpfs does its thing: + http://cvs.savannah.gnu.org/viewvc/*checkout*/httpfs/README?root=hurdextras + <congzhang> if I can't cd to /http:/host/a/b how to get + /http:/host/a/b/c.html, even the file exist? + <pinotree> you don't cd in http + <pinotree> cd is for changing directory, which does not apply to a protocol + like http which is not fs-oriented + <congzhang> yes, I agree with you, http was not fs-oriented + <congzhang> so httpfs was not so useful + <rekado> You can access the document directly, though, can't you? + <congzhang> rekado: I try once more + <congzhang> I can't + <congzhang> so, the httpfs need some extend, http protocol was not fs + oriented, so need some extend to make it work with file system + <pinotree> http is not designed for file system usage, so extending it is + useless + <congzhang> or, httpfs was not so useful + <pinotree> there are many other protocols for file systems + <congzhang> I don't think so + <pinotree> i do + <congzhang> if we can't make it more useful, remove it from hurd rep, or + extend it more useful + <congzhang> add some more rule, to make it work with file system + <pinotree> no + <congzhang> some paradox in it + <pinotree> which paradox? + <congzhang> for http vs file system + <pinotree> ??? + <congzhang> tree oriented and star topology oriented? + <pinotree> you don't make any sense diff --git a/hurd/translator/mtab/discussion.mdwn b/hurd/translator/mtab/discussion.mdwn index ca6a86fd..0734e1e6 100644 --- a/hurd/translator/mtab/discussion.mdwn +++ b/hurd/translator/mtab/discussion.mdwn @@ -91,8 +91,7 @@ understanding of the translator mechanism and Hurd interfaces in general. <kuldeepdhaka> braunr, whats ur opinion? <pinotree> you don't need a mtab to "unmount" things on hurd <braunr> kuldeepdhaka: hum, have you read the project idea ? - <braunr> - http://darnassus.sceen.net/~hurd-web/community/gsoc/project_ideas/mtab/ + <braunr> A more promising approach is to have mtab exported by a special translator, which gathers the necessary information on demand. This could work by traversing the tree of translators, asking each one for mount @@ -143,3 +142,1981 @@ understanding of the translator mechanism and Hurd interfaces in general. <braunr> what ? <braunr> the content is generated on open <kuldeepdhaka> ooh, ok + + +# IRC, freenode, #hurd, 2013-06-04 + + <safinaskar> how to see list of all connected translators? + <braunr> you can't directly + <braunr> you can use ps to list processes and guess which are translators + <braunr> (e.g. everything starting with /hurd/) + <braunr> a recursive call to obtain such a list would be useful + <braunr> similar to what's needed to implement /proc/mounts + + +# IRC, freenode, #hurd, 2013-06-25 + +In context of [[open_issues/mig_portable_rpc_declarations]]. + + <teythoon> should I go for an iterator like interface instead? + <teythoon> btw, what's the expected roundtrip time? + <braunr> don't think that way + <braunr> consider the round trip delay as varying + <teythoon> y, is it that bad? + <braunr> no + <braunr> but the less there is the better + <braunr> we think the same with system calls even if they're faster + <braunr> the delay itself isn't the real issue + <braunr> look at how proc provides information + <braunr> (in procfs for example) + + +## IRC, freenode, #hurd, 2013-06-26 + + <teythoon> so tell me about the more hurdish way of dealing with that issue + <teythoon> creating a specialized translator for this? + + <braunr> you need to avoid thinking with centralization in mind + <braunr> the hurd is a distributed system in practice + <braunr> i think proc is the only centralized component in there + <teythoon> braunr: would having an mtab translator and having fs + translators register to thae be acceptable? + <teythoon> that* + <braunr> teythoon: why do you want to centralize it ? + <braunr> translators already register themselves when they get attached to + a node + <braunr> we don't want an additional registration + <braunr> have you read the link we gave you ? + <teythoon> I did and I got the message, but isn't the concept of + /proc/mounts or a mtab file already a centralized one? + <braunr> that doesn't mean the implementation has to be + <braunr> and no, i don't think it's centralized actually + <braunr> it's just a file + <braunr> you can build a file from many sources + <teythoon> or if we do it your way recursing on fs translators *but* + restricting this to root owned translators also suffering from + centralization wrt to the root user? I mean the concept of all mounted + filesystems does not apply cleanly to the hurd + <braunr> i don't understand + <braunr> restricting to the root user doesn't mean it's centralized + <braunr> trust has nothing to do with being centralized + <teythoon> I guess I'm not used to thinking this way + <braunr> teythoon: i guess that's the main reason why so few developers + work on the hurd + <teythoon> also the way fs notification is done is also centralized, that + could also be done recursively + <braunr> what doyou call fs notification ? + <teythoon> and the information I need could just be stuffed into the same + mechanism + <teythoon> fs translators being notified of system shutdown + <braunr> right + <braunr> that gets a bit complicated because the kernel is also a + centralized component + <braunr> it knows every memory object and their pagers + <braunr> it manages all virtual memory + <braunr> there are two different issues here + <braunr> syncing memory and shutting down file systems + <braunr> the latter could be done recursively, yes + <braunr> i wonder if the former could be delegated to external pagers as + well + <braunr> teythoon: but that's not the focus of your work aiui, it would + take much time + <teythoon> sure, but missing an mtab file or better yet /proc/mounts could + be an issue for me, at least a cosmetic one, if not a functional one + <braunr> i understand + <teythoon> and hacking up a quick solution for that seemed like a good + exercise + <braunr> i suggest you discuss it with your mentors + <braunr> they might agree to a temporary centralized solution + <braunr> although i don't think it's much simpler than the recursive one + <teythoon> braunr: would that be implemented in libdiskfs and friends? + <braunr> teythoon: i'm not sure, it might be a generic fs operation + <braunr> libnetfs etc.. are also mount points + <teythoon> so where would it go if it was generic? + <braunr> libfshelp perhaps + <teythoon> translator startup is handled in start-translator-long.c, so in + case a startup is successful, I'd add it to a list? + <braunr> i'd say so, yes + <teythoon> would that cover all cases, passive and active translators? + <braunr> that's another question + <braunr> do we consider passive translators as mounted ? + <teythoon> ah, that was not what i meant + <braunr> i know + <braunr> but it's related + <teythoon> start b/c of accessing a passive one vs. starting an active one + using settrans + <braunr> start_translator_xxx only spawn active translators + <braunr> it's the same + <teythoon> ok + <braunr> the definition of a passive translator is that it starts the + active translator on access + <teythoon> yeah I can see how that wouldn't be hard to implement + <braunr> i think we want to include passive translators in the mount table + <braunr> so registration must happen before starting the active one + <teythoon> so it's a) keeping a list of active translators and b) add an + interface to query fs translators for this list and c) an interface to + query mtab style information? + <braunr> keeping a list of all translators attached + <braunr> and yes + <braunr> well + <braunr> a is easy + <braunr> b is the real work + <braunr> c would be procfs using b + <teythoon> oh? I thought recursing on the translators and querying info + would be separate operations? + <braunr> why so ? + <braunr> the point is querying recursively :) + <braunr> and when i say recursively, it's only a logical view + <teythoon> ok, yes, it can be implemented this way, so we construct the + list while recursing on the translators + <braunr> i think it would be better to implement it the way looking up a + node is done + <teythoon> in a loop, using a stack? + <braunr> iteratively + <braunr> a translator would provide information about itself (if + supported), and referrences to translators locally registered to it + <teythoon> could you point me to the node lookup? + <teythoon> ah, yes + <braunr> eg., you ask /, it tells you it's on /dev/hd0, read-write, with + options, and send rights to /home, /proc, etc.. + <braunr> well rights, references + <braunr> it could be the path itself + <teythoon> rights as in a port to the translators? + <braunr> i think the path would be better but i'm not sure + <braunr> it would also allow you to check the permissions of the node + before querying + <teythoon> path would be nicer in the presence of stacked translators + <braunr> and obviously you'd have the path right away, no need to provide + it in the reply + <teythoon> true + + <teythoon> braunr: if we want to list passive translators (and I agree, we + should), it isn't sufficient to touch libfshelp, as setting a passive + translator is not handled there, only the startup + <braunr> teythoon: doesn't mean you can't add something there that other + libraries will use + <braunr> so yes, not sufficient + + +## IRC, freenode, #hurd, 2013-06-29 + + <teythoon> braunr: diskfs_S_fsys_set_options uses diskfs_node_iterate to + recurse on active translators if do_children is given + <teythoon> braunr: I wonder how fast that is in practice + <teythoon> braunr: if it's fast enough, there might not even be a need for + a new function in fsys.defs + <teythoon> and no need to keep a list of translators for that reason + <teythoon> braunr: if it's not fast enough, then diskfs_S_fsys_set_options + could use the list to speed this up + <braunr> teythoon: on all nodes ? + <teythoon> braunr: i believe so, yes, see libdiskfs/fsys-options.c + <braunr> teythoon: well, if it really is all node, you clearly don't want + that + + +## IRC, freenode, #hurd, 2013-07-01 + + <teythoon> I've ment to ask, the shiny new fsys_get_translators interface, + should it return the options for the queried translator or not? + <braunr> i don't think it should + <teythoon> ok + <braunr> let's walk through why it shouldn't + <teythoon> may I assume that the last argument returned by fsys_get_options + is the "source"? + <braunr> how would you know these options ? + <braunr> the source ? + <teythoon> I wouldn't actually + <braunr> yes, you wouldn't + <braunr> you'd have to ask the translators for that + <braunr> so the only thing you can do is point to them + <teythoon> well, the device to include in the mtab file + <braunr> and the client asks + <braunr> i don't know fsys_get_options tbh + <teythoon> well, both tmpfs and ext2fs print an appropriate value for + "device" as last argument + <braunr> looks like a bad interface to me + <braunr> options should be options + <braunr> there should be a specific call for the device + <braunr> but if everyone agrees with the options order, you can do it that + way for now i guess + <teythoon> one that could be used to recreate the "mount" using either + mount or settrans + <braunr> just comment it where appropriate + <teythoon> I thought that'd be the point? + <braunr> ? + <teythoon> % fsysopts tmp + <teythoon> /hurd/tmpfs --writable --no-inherit-dir-group --no-sync 48K + <braunr> where is the device ? + <teythoon> % settrans -ca tmp $(fsysopts tmp) + <braunr> 15:56 < teythoon> well, both tmpfs and ext2fs print an appropriate + value for "device" as last argument + <teythoon> 48K + <braunr> i don't see it + <braunr> really ? + <teythoon> yes + <braunr> what about ext2fs ? + <braunr> hm ok i see + <teythoon> % fsysopts / + <teythoon> ext2fs --writable --no-inherit-dir-group --sync=10 + --store-type=typed device:hd0s1 + <braunr> i don't think you should consider that as devices + <braunr> but really translator specific options + <pinotree> agree + <teythoon> I don't ;) + <teythoon> b/c the translator calling convention is hardcoded in the mount + utility + <braunr> ? + <teythoon> I think it's reasonable to assume that this mapping can be + reversed + <pinotree> theorically you can write a translator that takes no arguments, + but just options + <braunr> the 48K string for tmpfs is completely meaningless + <braunr> in fstab, it should be none + <pinotree> "tmpfs" + <braunr> the linux equivalent is the size option + <braunr> no, none + <braunr> it's totally ignored + <braunr> and it's recommended to set none rather than the type to avoid + confusion + <teythoon> u sure? + <teythoon> % settrans -cga tmp /hurd/tmpfs --mode=666 6M + <teythoon> % settrans -cga tmp /hurd/tmpfs --mode=666 6M + <teythoon> % fsysopts tmp + <teythoon> /hurd/tmpfs --writable --no-inherit-dir-group --no-sync 6M + <braunr> i've not explained myself clearly + <braunr> it's not ignored by the translator + <braunr> but in fstab, it should be in the options field + <braunr> it's not the source + <braunr> clearly not + <teythoon> ah + <braunr> now i'm talking about fstab, but iirc the format is similar in + mtab/mounts + <pinotree> close, but not the same + <braunr> yes, close + <teythoon> ok, so I'll put a method into libfshelp so that translators can + explicitly set a device and patch all existing translators to do so? + <braunr> teythoon: what i meant is that, for virtual vile systems (actually + file systems with no underlying devices), the device field is normally + ignored + <braunr> teythoon: why do you need that for exactly + <teythoon> right + <pinotree> do they even have a "device" field? + <braunr> (i can see why but i'd like more visibility) + <braunr> pinotree: not yet + <braunr> pinotree: that's what he wants to add + <braunr> but i'd like to see if there is another way to get the information + <braunr> 16:05 < braunr> teythoon: why do you need that for exactly + <teythoon> well if I'm constructing a mtab entry I need a value for the + device field + <braunr> do we actually need it to be valid ? + <teythoon> not necessarily I guess + <braunr> discuss it with your mentors then + <youpi> it has to be valid for e2fsck checks etc. + <braunr> doesn't e2fsck check fstab actually ? + <youpi> i.e. actually for the cases where it's trivial + <youpi> fstab doesn't tell it whether it's mounted + <youpi> I mean fsck checking whether it's mounted + <youpi> not fsck -a + <braunr> oh + <braunr> couldn't we ask the device instead ? + <braunr> looks twisted too + <youpi> that'd mean patching a lot of applications which do similar checks + <braunr> yes + <braunr> teythoon: propose an interface for that with your mentors then + <teythoon> yeah, but couldn't you lay it out a little, I mean would it be + one procedure or like three? + <braunr> 16:04 < teythoon> ok, so I'll put a method into libfshelp so that + translators can explicitly set a device and patch all existing + translators to do so? + <teythoon> ok + <braunr> why three ? + <teythoon> no, I mean when adding stuff to fsys.defs + <braunr> i understood that + <braunr> but why three ? :) + <teythoon> it'd be more generic + <braunr> really ? + <braunr> please show a quick example of what you have in mind + <teythoon> i honestly don't know, thus I'm asking ;) + <braunr> well first, this device thing bothers me + <braunr> when you look at how we set up our ext2fs translators, you can see + they use device:xxx + <braunr> and not /dev/xxx + <braunr> but ok, let's assume it's harmless + <teythoon> ok, but isn't the first way actually better? + <braunr> i think it ends up being the same + <braunr> ideally, that's what we want to use as device path + <teythoon> but you can recreate a storeio translator using the device:xxx + info, the node is useless for that + <braunr> so that we don't need to explicitely set it + <braunr> ? + <braunr> what do you mean ? + <teythoon> well, fsysopts / tells currently tells me device:hd0s1 + <braunr> for /, there isn't much choice + <braunr> /dev isn't there yet + <teythoon> ah, got it + <teythoon> that's why it differs... + <braunr> differs ? + <braunr> from what ? + <braunr> other ext2fs translators are set the same way by the debian + installer for example + <teythoon> % fsysopts /media/scratch + <teythoon> /hurd/ext2fs --writable --no-inherit-dir-group /dev/hd1s1 + <teythoon> here it uses the path to the node + <braunr> that's weird + <braunr> was that done by the debian installer ? + <teythoon> ah no, that was me + <braunr> :p + <braunr> $ fsysopts /home + <braunr> /hurd/ext2fs --writable --no-inherit-dir-group --store-type=device + hd0s6 + <braunr> so as you can see, it's not that simple to infer the device path + <teythoon> oho, yet another way ;) + <teythoon> right then + <pinotree> isn't device:hd0s1 as shortcut for specifying the store type, as + done with --store-type=device hd0s1? + <braunr> but perhaps we don't need to + <braunr> yes it is + <pinotree> iirc it's something libstore does, per-store prefixes + <braunr> ah that sucks + <braunr> teythoon: you may need to normalize those strings + <braunr> so that they match what's in fstab + <braunr> i.e. unix /dev paths + <braunr> otherwise e2fsck still won't be able to find the translators + mounting the device + <braunr> well, if it's mounted actually + <braunr> it just needs to find the matching line in mtab aiui + <braunr> so perhaps a libfshelp function for that, yes + <teythoon> braunr: so you suggest adding a normalizing function to + libfshelp that creates a /dev/path? + <braunr> yes + <braunr> used by the call you intend to add, which returns that device + string as found in fstab + <teythoon> found in fstab? so this would only work for translators managed + by fstab? + <braunr> no + <teythoon> ah + <teythoon> a string like the ones found in fstab? + <braunr> yes + <braunr> so that fsck and friends are able to know whether a device is + mounted or not + <braunr> i don't see any other purpose for that string in mtab + <braunr> you'd take regular paths as they are, convert device:xxx to + /dev/xxx, and return "none" for the rest i suppose + <teythoon> ok + <braunr> i'm not even sure it's right + <braunr> youpi: are you sure it's required ? + <teythoon> well it's a start and I think it's not too much work + <braunr> aiui, e2fsck may simply find the mount point in fstab, and ask the + translator if it's mounted + <teythoon> we can refine this later on maybe? + <braunr> or rather, init scripts, using mountpoint, before starting e2fsck + <braunr> teythoon: sure + <teythoon> there's this mountpoint issue... I need to run fsysopts / + --update early in the boot process + <teythoon> otherwise the device ids returned by stat(2)ing / are wrong and + mountpoint misbehaves + <teythoon> i guess b/c it's the rootfs + <braunr> device ids ? + <teythoon> % stat / | grep Device + <teythoon> Device: 3h/3d Inode: 2 Links: 22 + <braunr> do you mean the major/minor identifiers ? + <teythoon> I do. if I don't do the --update i get seemingly random values + <braunr> i guess that's expected + <braunr> we don't have major/minor values + <braunr> well, they're emulated + <teythoon> well, if that's fixable, that'd be really nice ;) + <braunr> we'll never have major/minor values + <teythoon> yeah, I understand that + <braunr> but they could be fixed by MAKEDEV when creating device nodes + <teythoon> but not having to call fsys_set_options on the rootfs to get the + emulation up to speed + <braunr> try doing it from grub + <braunr> not sure it's possible + <braunr> but worth checking + <teythoon> by means of an ext2fs flag? + <braunr> yes + <braunr> if there is one + <braunr> i don't know the --update flag, is it new from your work ? + <teythoon> braunr: no, it's been there before. -oremount gets mapped to + that + <braunr> it's documented by fsysopts, but not by the ext2fs translators + <teythoon> libdiskfs source says something about flushing buffers iirc + <braunr> -s + <braunr> what does it do ? + <braunr> teythoon: ok + <teythoon> braunr: so the plan is to automatically generate a device path + from the translators argz vector but to provide the functionality so + translators can set a more appropriate value? did I get the last part of + the discussion right? + <braunr> not set, return + <teythoon> yeah return from the procedure but settable using libfshelp? + <braunr> why settable ? + <braunr> you'd have a fsys call to obtain the dev string, and the server + side would call libfshelp on the fly to obtain a normalized value and + return it + <teythoon> ah, make a function overrideable that returns an appropriate + response? + <braunr> overrideable ? + <teythoon> like netfs_append_args + <braunr> you wouldn't change the command line, no + <teythoon> isn't that done using weak references or something? + <teythoon> no I know + <braunr> sorry i'm lost then + <teythoon> never mind, I'll propose a patch early to get your feedback + <youpi> braunr: am I sure that _what_ is required? + <youpi> the device? + <youpi> e2fsck surely needs it, yes + <braunr> a valid device path, yes + <youpi> it can't rely only on fstab + <braunr> yes + <youpi> since users may mount things by hand + <braunr> i've used strace on it and it does perform lookups there + <braunr> (although i also saw uuid magic that i guess wouldn't work yet on + the hurd) + + +## IRC, freenode, #hurd, 2013-07-03 + + <teythoon> I added a procedure to fsys.defs, added a server stub to my + tmpfs translator and wrote a simple client, but something hasn't picked + up the new message yet + <teythoon> % ./mtab tmp + <teythoon> ./mtab: get_translator_info: (ipc/mig) bad request message ID + <teythoon> I guess it's libhurduser.so from glibc, not sure though... + <braunr> glibc would only have the client calls + <braunr> what is "% ./mtab tmp" ? + <teythoon> mtab is my mtab tool/soon to be a translator testing thing, tmp + is an active tmpfs with the appropriate server stub + <braunr> so mtab has the client call, right ? + <teythoon> yes + <braunr> then tmpfs doesn't + <teythoon> so what to do about it? + <teythoon> i set LD_LIBRARY_PATH to my hurd builds lib dir, is that + preserved by settrans -a? + <pinotree> not really + <braunr> not at all + <braunr> there is a wiki entry about that iirc + <pinotree> http://darnassus.sceen.net/~hurd-web/hurd/debugging/translator/ + <teythoon> yeah, I read it too once + <teythoon> ah + <braunr> on the other hand, using export to set the environment should do + the work + <teythoon> yes, that did the trick, thanks :) + * teythoon got his EOPNOPSUPP... *nomnomnom + <braunr> ? + <braunr> same error ? + <teythoon> well I stubbed it out + <braunr> oh + <teythoon> no, that's what I've been expecting ;) + <pinotree> great + <braunr> :) + <braunr> yes that's better than "mig can't find it" + <teythoon> braunr: in that list of active and passive translators that will + have to be maintained, do you expect it should carry more information + other than the relative path to that translator? + <braunr> like what ? + <teythoon> dunno, maybe like a port to any active translator there + <teythoon> should we care if any active translator dies and remove the + entry if there's no passive translator that could restart it again? + <braunr> don't add anything until you see it's necessary or really useful + <braunr> yes + <braunr> think of something like sshfs + <braunr> when you kill it, it's not reported by mount any more + <teythoon> well, for a dynamically allocated list of strings I could use + the argz stuff, but if we'd ever add anything else, we'd need a linked + list or something, maybe a hash table + <teythoon> yes, I thought that'd be useful + <braunr> use libihash for no + <braunr> now + <teythoon> braunr: but what would I use as keys? the relative path should + be unique (unless translators are stacked... hmmm), but that's the value + I'd like to store and ihash keys are pointers + <teythoon> stacked translators are an kinda interesting case for mtab + anyways... + <braunr> why not store the string address ? + <braunr> i suppose that, for stacked translators, the code querying + information would only return the topmost translator + <braunr> since this is the one which matters for regular clients (if i'm + right) + <teythoon> wouldn't that map strings that are equal but stored at different + locations to different values? + <teythoon> that'd defeat the point + <teythoon> I suppose so, yes + <braunr> then add a layer that looks for existing strings before adding + <braunr> the list should normally be small so a linear lookup is fine + <teythoon> yeah sure, but then there's little advantage of using ihash in + the first place, isn't it? + <braunr> over what ? + <teythoon> over not using it at all + <braunr> how would you store the list then ? + <teythoon> it's either ll or ll+ihash + <braunr> uh no + <braunr> let me check + <braunr> there is ihash_iterate + <braunr> so you don't need a linked list + <teythoon> so how do I store my list of strings to deduplicate the keys? + <braunr> you store pointers + <braunr> and on addition, you iterate over all entries, making sure none + matches the new one + <braunr> and if it does, you replace it i guess + <braunr> depending on how you design the rest + <teythoon> in an dynamically allocated region of memory? + <braunr> i don't understand + <braunr> your strings should be dynmaically allocate, yes + <teythoon> no the array of char * + <braunr> your data structure being managed by libihash, you don't care + about allocation + <braunr> what array ? + <teythoon> ah, got it... + <teythoon> right. + <braunr> there is only one structure here, an ihash of char * + <teythoon> yes, I got the picture ;) + <braunr> goo + <braunr> d + <braunr> actually, the lookup wouldn't be linear since usually, hash tables + have stale entries + <teythoon> heh... what forest?!? + <braunr> but that's ok + <braunr> teythoon: ? + <teythoon> the one I couldn't make out b/c of all the trees... + <braunr> ? + <teythoon> ah, it's not important. there is this saying over here, not sure + if there's an english equivalent + <braunr> ok got it + <braunr> we have the same in french + <teythoon> I ran into a problem with my prototype + <teythoon> if an translator is set in e. g. diskfs_S_file_set_translator, + how do I get the path to that node? + <teythoon> I believe there cannot be a way to do that, b/c the mapping is + not bijective + <braunr> it doesn't have to be + <teythoon> ok, so how do I get *a* path for this node? + <braunr> that's another question + <braunr> do you see how the node is obtained ? + <braunr> np = cred->po->np; + <teythoon> yes + <braunr> the translation occurred earlier + <braunr> you need to find where + <braunr> then perhaps, you'll need to carry the path along + <braunr> or if you're lucky, it will still be there somewhere + <teythoon> the translation from path to node? + <braunr> yes + <teythoon> doesn't that happen in the client? and the client hands a file_t + to the file_set_translator routine? + <braunr> the relative lookup can't happen in the client + <braunr> the server can (and often does) retain information between two + RPCs + <teythoon> uh, I can access information from a previous rpc? is that + considered safe? + <braunr> think of open() then read() + <braunr> a simple int doesn't carry enough information + <braunr> that's why it's a descriptor + <teythoon> ah, the server retains some state, sure + <braunr> what it refers to is the state retained between several calls + <braunr> the object being invoked by clients + <braunr> teythoon: what is the "passive" parameter passed to + diskfs_S_file_set_translator ? + <teythoon> braunr: argz vector of the passive translator + <braunr> so it is a name + <braunr> but we also want active translators + <braunr> and what is active ? + <teythoon> not the name of the node though + <teythoon> active is the port (?) to the active translator + <teythoon> I guess + <braunr> fsys_t, looks that way yes + <braunr> i suppose you could add the path to the peropen structure + <teythoon> ok + <braunr> see diskfs_make_peropen + <teythoon> braunr: but translation happens in dir_lookup + <teythoon> in all places I've seen diskfs_make_peropen used, the path is + not available + <teythoon> why did you point me to diskfs_make_peropen? + <teythoon> s/dir_lookup/diskfs_lookup/ + <teythoon> diskfs_lookup operates on struct node, so the path would have to + be stored there, right? + <braunr> teythoon: dir_lookup should call diskfs_make_peropen + <braunr> at least diskfs_S_dir_lookup does + <braunr> and the path is present there + <teythoon> braunr: right + + <teythoon> hrm... I added a path field to struct peropen and initialize it + properly in diskfs_make_peropen, but some bogus values keep creeping in + :/ + <braunr> first of all, make it a dynamically allocated string + <teythoon> it is + <braunr> not a fixed sized embedded array + <braunr> good + <teythoon> yes + <braunr> if you really need help debugging what's happening, feel free to + post your current changes somewhere + <teythoon> there is a struct literal in fsys-getroot.c, but i fixed that as + well + <teythoon> % ./mtab tmp + <teythoon> none tmp ../tmpfs/tmpfs writable,no-inherit-dir-group,no-sync 0 + 0 + <teythoon> none tmp/bar ../tmpfs/tmpfs + writable,no-inherit-dir-group,no-sync 0 0 + <teythoon> none tmp/foo ../tmpfs/tmpfs + writable,no-inherit-dir-group,no-sync 0 0 + <teythoon> none tmp/foo/bar ../tmpfs/tmpfs + writable,no-inherit-dir-group,no-sync 0 0 + <teythoon> :) + + +## IRC, freenode, #hurd, 2013-07-10 + + <teythoon> btw, I read getcwd.c and got the idea + <teythoon> however this situation is different afaict + <teythoon> getcwd has a port to the current working directory, right? + <teythoon> so they can do open_dir with .. as relative path + <teythoon> but all I've got is a port referencing the node the translator + is being attached to + <teythoon> s/open_dir/dir_lookup/ + <teythoon> and that is not necessarily a directory, so dir_lookup fails + with not a directory + <teythoon> as far as I can see it is not possible to get the directory a + node is in from a port referencing that node + <teythoon> dir_lookup has to be handled by all nodes, not just directories + <teythoon> but file nodes only support "looking up" the empty string + <teythoon> not empty, but null: + <teythoon> This call is required to be supported by all files (even + non-directories) if the filename is null, and should function in that + case as a re-open of the file. */ + <braunr> why do you want the directory ? + <braunr> 10:40 < teythoon> as far as I can see it is not possible to get + the directory a node is in from a port referencing that node + <teythoon> to readdir(3) it and figure out the name of the node the + translator is bound to + <teythoon> similar to what getcwd does + <braunr> that's out of the question + <teythoon> wasn't that was youpi was suggesting? + <braunr> you may have a lot of nodes in there, such a lookup shouldn't be + done + <braunr> i didn't see that detail + <teythoon> "│ Concerning storing the path, it's a bit sad to have to do + that, and + <teythoon> │ it'll become wrong if one moves the mount points. Another + way would + <teythoon> │ be to make the client figure it out by itself from a port to + the mount + <teythoon> │ point, much like glibc/sysdeps/mach/hurd/getcwd.c. It'll be + slower, but + <teythoon> │ should be safer. The RPC would thus return an array of + ports to the + <teythoon> │ mount points instead of an array of strings. + <braunr> yes i remember that + <braunr> but i didn't understand well how getcwd work + <braunr> s + <braunr> another scalability issue + <braunr> not a big one though, we rarely have translators in directories + with thousands of nodes + <braunr> so why not + <braunr> teythoon: do it as youpi suggested + <braunr> well if you can + <braunr> eh + <braunr> if not, i don't know + <braunr> 10:47 < teythoon> │ it'll become wrong if one moves the mount + points. Another way would + <teythoon> yes, I know... :/ + <teythoon> well, I'm not even sure it is possible to get the directory a + node is in from the port referencing the node + <teythoon> as in, I'm not sure if the information is even there + <teythoon> b/c a filesystem is a tree, directories are nodes and files are + leafs + <teythoon> all non-leaf nodes reference their parent to allow traversing + the tree starting from any directory + <teythoon> but why would a leaf reference its parent(s - in case of + hardlinks)? + <braunr> uh, for the same reason ? + <teythoon> sure, it would be nice to do that, but I dont think this is + possible on unixy systems + <braunr> ? + <teythoon> you cannot say fchdir(2) to a fd that references a file + <braunr> do you mean /path/to/file/../ ? + <teythoon> yes + <teythoon> only that /path/to/file is given as fd or port + <braunr> when i pasted + <braunr> 10:49 < braunr> 10:47 < teythoon> │ it'll become wrong if one + moves the mount points. Another way would + <braunr> i was actually wondering if it was true + <teythoon> ah + <braunr> why can't the path be updated at the same time ? + <braunr> it's a relative path anyway + <braunr> completely managed by the parent translator + <teythoon> ah + <teythoon> right + <teythoon> it's still kind of hacky, but I cannot see how to do this + properly + <braunr> hacky ? + <teythoon> but yes, updating the path should work I guess + <teythoon> or sad + <braunr> what i find hacky is to set translators in two passes + <braunr> otherwise we'd only keep the translator paths + <braunr> not all paths + <teythoon> true + <braunr> but then, it only concerns open nodes + <braunr> and again, there shouldn't be too many of them + <braunr> so actually it's ok + <teythoon> braunr: I understand the struct nodes are cached in libdiskfs, + so wouldn't it be easier to attach the path to that struct instead of + struct peropen so that all peropen objects reference the same node + object? + <teythoon> so that the path can be updated if anyone dir_renames it + <teythoon> *all peropen objects derived from the same file name that is + <braunr> teythoon: i'm not sure + <braunr> nodes could be real nodes (i.e. inodes) + <braunr> there can be several paths for the same inode + <teythoon> braunr: I'm aware of that, but didn't we agree the other day + that any path would do? + <braunr> i don't remember we did + <braunr> i don't know the details well, but i don't think setting a + translator on a hard link should set the translator at the inode level + <braunr> on the other hand, if a new inode is created to replace the + previous one (or stack over it), then storing the path there should be + fine + <teythoon> braunr: I don't think I can update the paths if they're stored + in the peropen struct + <teythoon> how would I get a reference to all those peropen objects? + <braunr> ? + <braunr> first, what's the context when you talkb about updating paths ? + <teythoon> well, youpi was concerned about renaming a mount point + <teythoon> and you implied that this could be managed + <braunr> can we actually do that btw ? + <teythoon> what? + <braunr> renaming a mount point + <teythoon> yep, just tried + <braunr> i mean, on a regular unix system like linux + <braunr> $ mv test blah + <braunr> mv: cannot move `test' to `blah': Device or resource busy + <braunr> (using sshfs so YMMV) + <pinotree> do you have anything (shells, open files, etc) inside it? + <braunr> no + <braunr> i'll try with an empty loop-mounted ext4 + <teythoon> I was testing on the Hurd, worked fine there even with a shell + inside + <braunr> same thing + <braunr> i consider it a bug + <braunr> we may want to check what posix says about it + <teythoon> o_O + <braunr> and decide not to support renaming + <teythoon> why? + <pinotree> start a discussion in ml, maybe roland can chime in + <braunr> it complicates things + <braunr> ah yes + <teythoon> sure, but I can move or rename a directory, why should it be + different with a mount point? + <braunr> because it's two of them + <braunr> they're stacked + <braunr> if we do want to support that, we must be very careful about + atomically updating all the stack + <teythoon> ok + <teythoon> braunr: I'm trying to detect dying translators to remove them + from the list of translators + <teythoon> what port can I use for that purpose? + <teythoon> if I use the bootstrap port, can I then use the same method as + init/init.c uses? just defining a do_mach_notify_dead_name function and + the multiplexer will call this? + <braunr> teythoon: possibly + <teythoon> braunr: we'll see shortly... + <teythoon> I get KERN_INVALID_CAPABILITY indicating that my bootstrap port + is invalid + <teythoon> when calling mach_port_request_notification to get the dead name + notification I mean + <braunr> is the translator already started when you do that ? + <teythoon> yes, at least I think so, I'm hooking into + diskfs_S_file_set_translator and that gets an active translators port + <teythoon> also the mach docs suggests that the notification port is + invalid, not the name port referencing the translator + <braunr> i guess it shouldn't + <braunr> oh + <braunr> please show the code + <braunr> but beware, if the translator is started, assume it could die + immediately + <teythoon> braunr: http://paste.debian.net/15371/ line 87 + <braunr> teythoon: notify can't be bootstrap + <braunr> what do you have in mind when writing this ? + <braunr> i'm not sure i follow + <teythoon> I want to be notified if an active translator goes away to + remove it from the list of translators + <braunr> ok but then + <braunr> create a send-once right + <braunr> and wait on it + <braunr> also, why do you want to be notified ? + <braunr> isn't this already done ? + <braunr> or can't do it lazily on access attempt ? + <braunr> +you + <teythoon> in the client? + <braunr> in the parent server + <braunr> what happens currently when a translator dies + <braunr> is the parent notified ? + <braunr> or does it give an invalid right ? + <teythoon> ah, i think so + <braunr> then you don't need to do it again + <teythoon> right, I overlooked that + + +## IRC, freenode, #hurd, 2013-07-12 + + <teythoon> recursively traversing all translators from / turns out to be + more dangerous than I expected + <teythoon> ... if done by a translator bound somewhere below /... + <teythoon> my interpretation is that the mtab translator tries to talk to + itself and deadlocks + <teythoon> (and as a side effect the whole system kinda just stops...) + + +## IRC, freenode, #hurd, 2013-07-15 + + <youpi> teythoon: did you discuss with braunr about returning port vs path + in fsys_get_children? + <teythoon> youpi: we did + <teythoon> as I wrote I looked at the getcwd source you pointed me at + <teythoon> and I started to code up something similar + <teythoon> but as far as I can see there's no way to tell from a port + referencing a file the directory this file is located in + <youpi> ah, right, there was a [0] mail + <youpi> teythoon: because it doesn't have a "..", right + <teythoon> about Neals concerns, he's right about not covering passive + translators very well + <teythoon> but the solution he proposed was similar to what I tried to do + first + <youpi> I don't like half-covering passive translators at all, to be honest + :) + <youpi> either covering them completely, or not at all, would be fine + <teythoon> and then braunr convinced me that the "recursive" approach is + more elegant and hurdish, and I came to agree with him + <teythoon> youpi: one could scan the filesystem at translator startup and + populate the list + <youpi> by "Neal's solution", you mean an mtab registry? + <teythoon> yes + <braunr> so, let's see what linux does when renaming parent directories + <teythoon> mount points you mean? + <youpi> teythoon: browsing the whole filesystem just to find passive + translators is costly + <youpi> teythoon, braunr: and that won't prevent the user from unexpectedly + starting other translators at will + <braunr> scary + <teythoon> youpi: but that requires the privilege to open the device + <youpi> the fact that a passive translator is set is nothing more than a + user having the intent of starting a translator + <braunr> linux retains the original path in the mount table + <youpi> heh + <teythoon> youpi: any unprivileged user can trigger a translator startup + <youpi> sure, but root can do that too + <youpi> and expect the system to behave nicely + <teythoon> but if I'm root and want to fsck something, I won't start + translators accessing the device just before that + <teythoon> but if there's a passive translator targetting the device, + someone else might do that + <youpi> root does not always completely control what he's doing + <youpi> linux for instance does prevent from mounting a filesystem being + checked + <teythoon> but still, including passive translators in the list would at + least prevent anyone starting an translator by accident, isn't that worth + doing then? + <youpi> if there's a way to prevent root too, that's better than having a + half-support for something which we don't necessarily really want + <youpi> (i.e. an exclusive lock on the underlying device) + <teythoon> right, that would also do the trick + <teythoon> btw, some programs or scripts seem to hardcode /proc/mounts and + procfs and I cannot bind a translator to /proc/mounts since it is + read-only and the node does not exist + <kilobug> IMHO automatically starting translators is a generic feature, and + passive translator is just a specific instance of it; but we could very + well have, like an "autofs" that automatically start translators in tar + archives and iso images, allowing to cd into any tar/iso on the system; + implementing such things is part of the Hurd flexibility, the "core + system" shouldn't be too aware on how translators are started + <youpi> so in the end, storing where the active translator was started + first seems okayish according to what linux has been exposing for decades + <youpi> kilobug: indeed + <teythoon> it could serve a mounts with a passive translator by default, or + a link to /run/mtab, or an simple file so we could bind a translator to + that node + <youpi> I'd tend to think that /proc/mounts should be a passive translator + and /run/mtab / /etc/mtab a symlink to it + <youpi> not being to choose the translator is a concern however + <teythoon> ok, I'll look into that + <youpi> it could be an empty file, and people be able to set a translator + on it + <teythoon> if it had a passive translator, people still could bind their + own translator to it later on, right? + <teythoon> afaics the issue currently is mostly, that there is no mounts + node and it is not possible to create one + <youpi> right + <teythoon> cool + <youpi> so with the actual path, you can even check for caller's permission + to read the path + <youpi> i.e. not provide any more information than the user would be able + to get from browsing by hand + <teythoon> sure, that concern of Neil's is easy to address + <youpi> I'm not so much concerned by stale paths being shown in mtab + <youpi> the worst that can happen is a user not being able to umount the + path + <youpi> but he can settrans -g it + <youpi> (which he can't on linux ;) ) + <teythoon> yes, and the device information is still valid + <youpi> yes + <braunr> despite the parent dir being renamed, linux is still able to + umount the new path + <teythoon> and so is our current umount + <braunr> good + <teythoon> (if one uses the mount point as argument) + <braunr> what's the current plan concerning /proc/mounts ? + <teythoon> serving a node with a passive translator record + <braunr> ? + <teythoon> so that /hurd/mtab / is started on access + <braunr> i mean, still planning on using the recursive approach instead of + a registry ? + <teythoon> ah + <teythoon> I do not feel confident enough to decide this, but I agree with + you, it feels elegant + <teythoon> and it works :) + <teythoon> modulo the translator deadlocking if it talks to itself, any + thoughts on that? + <youpi> it is a non-threaded translator I guess? + <teythoon> currently yes + <youpi> making it threaded should fix the issue + <teythoon> I tried to make the mtab translator multithreaded but that + didn't help + <youpi> that's odd + <teythoon> maybe I did it wrong + <braunr> i don't find it surprising + <braunr> well, not that surprising :p + <braunr> on what lock does it block ? + <teythoon> as far as i can see the only difference of hello and hellot-mt + is that it uses a different dispatcher and has lot's of locking, right? + <teythoon> braunr: I'm not sure, partly because that wrecked havoc on the + whole system + <teythoon> it just freezes + <teythoon> but it wasn't permanent. once i let it running and it recovered + <braunr> consider using a subhurd + <teythoon> ah right, I ment to set up one anyway, but my first attempts + were not successful, not sure why + <teythoon> anyway, is there a way to prevent this in the first place? + <teythoon> if one could compare ports that'd be helpful + <youpi> Mmm, did you try to simply compare the number? + <teythoon> with the bootstrap port I presume? + <youpi> Mmm, no, the send port and the receive port would be different + <youpi> no, with the receive port + <teythoon> ah + <braunr> comparing the numbers should work + <braunr> youpi: no they should be the same + <youpi> braunr: ah, then it should work yes + <braunr> that's why there are user ref counts + <youpi> ok + <braunr> only send-once rights have their own names + <teythoon> btw, I'll push my work to darnassus from now on, + e.g. http://darnassus.sceen.net/gitweb/?p=teythoon/hurd.git;a=shortlog;h=refs/heads/feature-mtab-translator-v3-wip + + +## [[open_issues/libnetfs_passive_translators]] + + +## IRC, freenode, #hurd, 2013-07-16 + + <teythoon> which port is the receive port of a translator? I mean, how is + it called in the source, there is no port in sight named receive anywhere + I looked. + <braunr> teythoon: what is the "receive port of a translator" ? + <teythoon> braunr: we talked yesterday about preventing the mtab deadlock + by comparing ports + <teythoon> I asked which one to use for the comparison, youpi said the + receive port + <braunr> i'm not sure what he meant + <braunr> it could be the receive port used for the RPC + <braunr> but i don't think it's exported past mig stub code + <teythoon> weird, I just reread it. I asked if i should use the bootstrap + port, and he said receive port, but it might have been addressed to you? + <teythoon> you were talking about send and receive ports being singletons + or not + <teythoon> umm + <braunr> no i answered him + <braunr> he was wondering if the receive port could actually be used for + comparison + <braunr> i said it can + <braunr> but still, i'm not sure what port + <braunr> if it's urgent, send him a mail + <teythoon> no, my pipeline is full of stuff I can do instead ;) + <braunr> :) + + +## IRC, freenode, #hurd, 2013-07-17 + + <teythoon> braunr: btw, comparing ports solved the deadlock in the mtab + translator rather easily + <braunr> :) + <braunr> which port then ? + <teythoon> currently I'm stuck though, I'm not sure how to address Neals + concern wrt to access permission checks + <teythoon> I believe it's called control port + <braunr> ok + <teythoon> the one one gets from doing the handshake with the parent + <braunr> i thought it was the bootstrap port + <braunr> but i don't know the details so i may be wrong + <braunr> anyway + <teythoon> yes + <braunr> what is the permission problem again ? + <teythoon> 871u73j4zp.wl%neal@walfield.org + <braunr> well, you could perform a lookup on the stored path + <braunr> as if opening the node + <teythoon> if I look at any server implementation of a procedure from + fs.defs (say libtrivfs/file-chmod.c [bad example though, that looks wrong + to me]), there is permission checking being done + <teythoon> any server implementation of a procedure from fsys.defs lacks + permission checks, so I guess it's being done somewhere else + <braunr> i must say i'm a bit lost in this discussion + <braunr> i don't know :/ + <braunr> can *you* sum up the permission problem please ? + <braunr> i mean here, now, in just a few words ? + <teythoon> ok, so I'm extending the fsys api with the get_children + procedure + <teythoon> that one should not return any children x/y if the user doing + the request has no read permissions on x + <braunr> really ? + <braunr> why so ? + <teythoon> the same way ls x would not reveal the existence of y + <braunr> i could also say unlike cat /proc/mounts + <braunr> i can see why we would want that + <braunr> i also can see why we could let this behaviour in place + <braunr> let's admit we do want it + <teythoon> true, but I thought this could easily be addressed + <braunr> what you could do is + <teythoon> now I'm not sure b/c I cannot even find the permission checking + code for any fsys_* function + <braunr> for each element in the list of child translators + <braunr> perform a lookup on the stored path on behalf of the user + <braunr> and add to the returned list if permission checks pass + <braunr> teythoon: note that i said lookup on the path, which is an fs + interface + <braunr> i assume there is no permission checking for the fsys interface + because it's done at the file (fs) level + <teythoon> i think so too, yes + <teythoon> sure, if I only knew who made the request in the first place + <teythoon> the file-* options have a convenient credential handle passed in + as first parameter + <teythoon> s/options/procedures/ + <teythoon> surely the fsys-* procedures also have a means of retrieving + that information, I just don't know how + <braunr> mig magic + <braunr> teythoon: see file_t in hurd_types.defs + <braunr> there is the macro FILE_INTRAN which is defined in subdirectories + (or not) + <teythoon> ah, retrieving the control port requires permissions, and the + fsys-* operations then operate on the control port? + <braunr> see libdiskfs/fsmutations.h for example + <braunr> uh yes but that's for < braunr> i assume there is no permission + checking for the fsys interface because it's done at the file (fs) level + <braunr> i'm answering < teythoon> sure, if I only knew who made the + request in the first place + <braunr> teythoon: do we understand each other or is there still something + fuzzy ? + <teythoon> braunr: thanks for the pointers, I'll read up on that a bit + later + <braunr> teythoon: ok + + +## IRC, freenode, #hurd, 2013-07-18 + + <teythoon> braunr: back to the permission checking problem for the + fsys_get_children interface + <teythoon> I can see how this could be easily implemented in the mtab + translator, it asks the translator for the list of children and then + checks if the user has permission to read the parent dir + <teythoon> but that is pointless, it has to be implemented in the + fsys_get_children server function + <braunr> yes + <braunr> why is it pointless ? + <teythoon> because one could circumvent the restriction by doing the + fsys_get_children call w/o the mtab translator + <braunr> uh no + <braunr> you got it wrong + <braunr> what i suggested is that fsys_get_children does it before + returning a list + <braunr> the problem is that the mtab translator has a different identity + from the users accessing it + <teythoon> yes, but I cannot see how to do this, b/c at this point I do not + have the user credentials + <braunr> get them + <teythoon> how? + <braunr> 16:14 < braunr> mig magic + <braunr> 16:15 < braunr> teythoon: see file_t in hurd_types.defs + <braunr> 16:16 < braunr> there is the macro FILE_INTRAN which is defined in + subdirectories (or not) + <braunr> 16:16 < braunr> see libdiskfs/fsmutations.h for example + <teythoon> i saw that + <braunr> is there a problem i don't see then ? + <braunr> i suppose you should define FSYS_INTRAN rather + <braunr> but the idea is the same + <teythoon> won't that change all the function signatures of the fsys-* + family? + <braunr> that's probably the only reason not to implement this feature + right now + <teythoon> then again, that change is probably easy and mechanic in nature, + might be an excuse to play around with coccinelle + <braunr> why not + <braunr> if you have the time + <teythoon> right, if this can be done, the mtab translator (if run as root) + could get credentials matching the users credentials to make that + request, right? + <braunr> i suppose + <braunr> i'm not sure it's easy to make servers do requests on behalf of + users on the hurd + <braunr> which makes me wonder if the mtab functionality shouldn't be + implemented in glibc eheheh .... + <braunr> but probably not + <teythoon> well, I'll try out the mig magic thing and see how painful it is + to fix everything ;) + <braunr> good luck + <braunr> honestly, i'm starting to think it's deviating too much from your + initial goal + <braunr> i'd be fine with a linux-like /proc/mounts + <braunr> with a TODO concerning permissions + <teythoon> ok, fine with me :) + <braunr> confirm it with the other mentors please + <braunr> we have to agree quickly on this + <teythoon> y? + + <teythoon> braunr: I actually believe that the permission issue can be + addressed cleanly and unobstrusively + <teythoon> braunr: would you still be opposed to the get_children approach + if that is solved? + <teythoon> the filesystem is a tree and the translators "creating" that + tree are a more coarse version of that tree + <teythoon> having a method to traverse that tree seems natural to me + <braunr> teythoon: it is natural + <braunr> i'm just worried it's a bit too complicated, unnecessary, and + out-of-scope for the problem at hand + <braunr> (which is /proc/mounts, not to forget it) + + +## IRC, freenode, #hurd, 2013-07-19 + + <teythoon> braunr: I think you could be a bit more optimistic and + supportive of the decentralized approach + <teythoon> I know the dark side has cookies and strong language and it's + mighty tempting + <teythoon> but both are bad for you :p + + +## IRC, freenode, #hurd, 2013-07-22 + + <youpi> teythoon: AIUI, you should be able to run the mtab translator as + no-user (i.e. no uid) + <teythoon> youpi: yes, that works fine + + <youpi> teythoon: so there is actually no need to define FSYS_INTRAN, doing + it by hand as you did is fine, right? + <youpi> (/me backlogs mails...) + <teythoon> youpi: yes, the main challenge was to figure out what mig does + and how the cpp is involved + <youpi> heh :) + <teythoon> my patch does exactly the same, but only for this one server + function + <teythoon> youpi: I'm confused by your mail, why are read permissions on + all path components necessary? + <braunr> teythoon: only execution normally + <youpi> teythoon: to avoid letting a user discover a translator running on + a hidden directory + <teythoon> braunr: exactly, and that is tested + <youpi> e.g. ~/home/foo is o+x, but o-r + <youpi> and I have a translator running on ~/home/foo/aZeRtYuyU + <youpi> I don't want that to show up on /proc/mounts + <braunr> youpi: i don't understand either: why isn't execution permission + enough ? + <teythoon> youpi: but that requires testing for read on the *last* + component of the *dirname* of your translator, and that is tested + <youpi> let me take another example :) + <youpi> e.g. ~/home/foo/aZeRtYuyU is o+x, but o-r + <youpi> and I have a translator running on ~/home/foo/aZeRtYuyU/foo + <youpi> ergl sorry, I meant this actually: + <teythoon> yes, that won't show up then in the mtab for users that are not + you and not root + <youpi> e.g. ~/home/foo is o+x, but o-r + <youpi> and I have a translator running on ~/home/foo/aZeRtYuyU/foo + <teythoon> ah + <teythoon> hmm, good point + <braunr> ? + * braunr still confused + <teythoon> well, qwfpgjlu is the secret + <teythoon> and that is revealed by the fsys_get_children procedure + <braunr> then i didn't understand the description of the call right + <braunr> > + /* check_access performs the same permission check as is + normally + <braunr> > + done, i.e. it checks that all but the last path components + are + <braunr> > + executable by the requesting user and that the last + component is + <braunr> > + readable. */ + <teythoon> braunr: youpi argues that this is not enough in this case + <braunr> from that, it looks ok to me + <youpi> the function and the documentation agree, yes + <youpi> but that's not what we want + <braunr> and that's where i fail to understand + <youpi> again, see my example + <braunr> i am + <braunr> 10:43 < youpi> e.g. ~/home/foo is o+x, but o-r + <braunr> ok + <youpi> so the user is not supposed to find out the secret + <braunr> then your example isn't enough to describe what's wron + <braunr> g + <youpi> checking read permission only on ~/home/foo/aZeRtYuyU will not + garantee that + <braunr> ah + <braunr> i thought foo was the last component + <youpi> no, that's why I changed my example + <braunr> hum + <braunr> 10:43 < youpi> e.g. ~/home/foo is o+x, but o-r + <braunr> 10:43 < youpi> and I have a translator running on + ~/home/foo/aZeRtYuyU/foo + <braunr> i meant, the last foo + <teythoon> still, this is easily fixed + <youpi> sure + <youpi> just has to be :) + <teythoon> youpi, braunr: so do you think that this approach will work? + <youpi> I believe so + <braunr> i still don't see the problem, so don't ask me :) + <braunr> i've been sick all week end and hardly slept, which might explain + <braunr> in the example, "all but the last path components" is + "~/home/foo/aZeRtYuyU" + <braunr> right ? + <youpi> braunr: well, I haven't looked at the details + <youpi> but be it the last, or but-last doesn't change the issue + <youpi> if my ~/hidden is o-r,o+x + <youpi> and I have a translator on ~/hidden/a/b/c/d/e + <youpi> checking only +x on hidden is not ok + <braunr> but won't the call also check a b c d ? + <youpi> yes, but that's not what matters + <youpi> what matters is that hidden is o-r + <braunr> hm + <youpi> so the mtab translator is not supposed to reveal that there is an + "a" in there + <braunr> ok i'm starting to understand + <braunr> so r must be checked on all components too + <youpi> yes + <braunr> right + <youpi> to simulate the user doing ls, cd, ls, cd, etc. + <braunr> well, not cd + <braunr> ah + <youpi> for being able to do ls, you have to be able to do cd + <braunr> as an ordered list of commands + <braunr> ok + <teythoon> agreed. can you think of any more issues? + <braunr> so both x and r must be checked + <youpi> so in the end this RPC is really a shortcut for a find + fsysopts + script + <youpi> teythoon: I don't see any + <braunr> teythoon: i couldn't take a clear look at the patch but + <braunr> do you perform a lookup on all nodes ? + <teythoon> yes, all nodes on the path from the root to the one specified by + the mount point entry in the active translator list + <braunr> let me rephrase + <braunr> do you at some point do a lookup, similar to a find, on all nodes + of a translator ? + <teythoon> no + <braunr> good + <teythoon> yes + <braunr> iirc, neal raised that concern once + <teythoon> and I'll also fix settrans --recursive not to iterate over *all* + nodes either + <braunr> great + <braunr> :) + <teythoon> fsys_set_options with do_children=1 currently does that (I've + only looked at the diskfs version) + + +## IRC, freenode, #hurd, 2013-07-27 + + <teythoon> youpi: ah, I just found msg_get_init_port, that should make the + translator detection feasible + + +## IRC, freenode, #hurd, 2013-07-31 + + <teythoon> braunr: can I discover the sender of an rpc message? + <braunr> teythoon: no + <braunr> teythoon: what do you mean by "sender" ? + <teythoon> braunr: well, I'm trying to do permission checks in the + S_proc_mark_essential server function + <braunr> ok so, the sending user + <braunr> that should be doable + <teythoon> I've got a struct proc *p courtesy of a mig intran mutation and + a port lookup + <teythoon> but that is not necessarily the sender, right? + <braunr> proc is really the server i know the least :/ + <braunr> there is permission checking for signals + <braunr> it does work + <braunr> you should look there + <teythoon> yes, there are permission checks there + <teythoon> but the only argument the rpc has is a mach_port_t refering to + an object in the proc server + <braunr> yes + <teythoon> anyone can obtain such a handle for any process, no? + <braunr> can you tell where it is exactly please ? + <braunr> i don't think so, no + <teythoon> what? + <braunr> 14:42 < teythoon> but the only argument the rpc has is a + mach_port_t refering to an object in the proc server + <teythoon> ah + <braunr> the code you're referring to + <braunr> a common way to give privileges to public objects is to provide + different types of rights + <braunr> a public (usually read-only) right + <braunr> and a privileged one, like host_priv which you may have seen + <braunr> acting on (modifying) a remote object normally requires the latter + <teythoon> http://paste.debian.net/20795/ + <braunr> i thought you were referring to existing code + <teythoon> well, there is existing code doing permission checks the same + way I'm doing it there + <braunr> where is it please ? + <braunr> mgt.c ? + <teythoon> proc/mgt.c (S_proc_setowner) for example + <teythoon> yes + <braunr> that's different + <teythoon> but anyone can obtain such a reference by doing proc_pid2proc + <braunr> the sender is explicitely giving the new uid + <braunr> yes but not anyone is already an owner of the target process + <braunr> (although it may look like anyone has the right to clear the owner + oO) + <teythoon> see, that's what made me worry, it is not checked who's the + sender of the message + <teythoon> unless i'm missing something here + <teythoon> ah + <teythoon> I am + <teythoon> pid2proc returns EPERM if one is not the owner of the process in + question + <teythoon> all is well + <braunr> ok + <braunr> it still requires the caller process though + <teythoon> what? + <braunr> see check_owner + <braunr> the only occurrence i find in the hurd is in libps/procstat.c + <braunr> MGET(PSTAT_PROCESS, PSTAT_PID, proc_pid2proc (server, ps->pid, + &ps->process)); + <braunr> server being the proc server AIUI + <teythoon> yes, most likely + <braunr> but pid2proc describes this first argument to be the caller + process + <teythoon> ah but it is + <braunr> ? + <teythoon> mig magic :p + <teythoon> MIGSFLAGS="-DPROCESS_INTRAN=pstruct_t reqport_find (process_t)" + \ + <teythoon> MIGSFLAGS="-DPROCESS_INTRAN=pstruct_t reqport_find (process_t)" + \ + <braunr> ah nice + <braunr> hum no + <braunr> this just looks up the proc object from a port name, which is + obvious + <braunr> what i mean is + <braunr> 14:53 < braunr> MGET(PSTAT_PROCESS, PSTAT_PID, proc_pid2proc + (server, ps->pid, &ps->process)); + <braunr> this is done in libps + <braunr> which can be used by any process + <braunr> server is the proc server for this process (it defines the process + namespace) + <teythoon> yes, but isn't the port to the proc server different for each + process? + <braunr> no, the port is the same (the name changes only) + <braunr> ports are global non-first class objects + <teythoon> and the proc server can thus tell with the lookup which process + it is talking to? + <braunr> that's the thing + <braunr> from pid2proc : + <braunr> S_proc_pid2proc (struct proc *callerp + <braunr> [...] + <braunr> if (! check_owner (callerp, p)) + <braunr> check_owner (struct proc *proc1, struct proc *proc2) + <braunr> "Returns true if PROC1 has `owner' privileges over PROC2 (and can + thus get its task port &c)." + <braunr> callerp looks like it should be the caller process + <braunr> but in libps, it seems to be the proc server + <braunr> this looks strange to me + <teythoon> yep, to me too, hence my confusion + <braunr> could be a bug that allows anyone to perform pid2proc + <teythoon> braunr: well, proc_pid2proc (getproc (), 1, ...) fails with + EPERM as expected for me + <braunr> ofc it does with getproc() + <braunr> but what forces a process to pass itself as the first argument ? + <teythoon> braunr: nothing, but what else would it pass there? + <braunr> 14:53 < braunr> MGET(PSTAT_PROCESS, PSTAT_PID, proc_pid2proc + (server, ps->pid, &ps->process)); + <braunr> everyone knows the proc server + <braunr> ok now, that's weird + <braunr> teythoon: does getproc() return the proc server ? + <teythoon> I think so, yes + <teythoon> damn those distributed systems, all of their sources are so + distributed too + <braunr> i suspect there is another layer of dark glue in the way + <teythoon> I cannot even find getproc :/ + <braunr> hurdports.c:GETSET (process_t, proc, PROC) + <braunr> that's the dark glue :p + <teythoon> ah, so it must be true that the ports to the proc server are + indeed process specific, right? + <braunr> ? + <teythoon> well, it is not one port to the proc server that everyone knows + <braunr> it is + <braunr> what makes you think it's not ? + <teythoon> proc_pid2proc (getproc (), 1, ...) fails with EPERM for anyone + not being root, but succeeds for root + <braunr> hm right + <teythoon> if getproc () were to return the same port, the proc server + couldn't distinguish these + <braunr> indeed + <braunr> in which case getproc() actually returns the caller's process + object at its proc server + <teythoon> yes, that is better worded + <braunr> teythoon: i'm not sure it's true actually :/ + <teythoon> braunr: well, exploit or it didn't happen + <braunr> teythoon: getproc() apparently returns a bootstrap port + <braunr> we must find the code that sets this port + <braunr> i have a hard time doing that :/ + <pinotree> isn't part of the stuff which is passed to a new process by + exec? + <teythoon> braunr: I know that feeling + <braunr> pinotree: probably + <braunr> still hard to find .. + <pinotree> search in glibc + <teythoon> braunr: exec/exec.c:1654 asks the proc server for the proc + object to use for the new process + <teythoon> so how much of hurd do I have to rebuild once i changed struct + procinfo in hurd_types.h? + <teythoon> oh noez, glibc uses it too :/ + + +## IRC, freenode, #hurd, 2013-08-01 + + <teythoon> I need some pointers on building the libc, specifically how to + point libcs build system to my modified hurd headers + <teythoon> nlightnfotis: hi + <teythoon> nlightnfotis: you rebuild the libc right? do you have any hurd + specific pointers for doing so? + <nlightnfotis> teythoon, I have not yet rebuild the libc (I was planning + to, but I followed other courses of action) Thomas had pointed me to some + resources on the Hurd website. I can look them up for you + <nlightnfotis> teythoon, here are the instructions + http://darnassus.sceen.net/~hurd-web/open_issues/glibc/debian/ + <nlightnfotis> and the eglibc snapshot is here + http://snapshot.debian.org/package/eglibc/ + <teythoon> nlightnfotis: yeah, I found those. the thing is I changed a + struct in the hurd_types.h header, so now I want to rebuild the libc with + that header + <teythoon> and I cannot figure out how to point libcs build system to my + hurd headers + <teythoon> :/ + <nlightnfotis> can you patch eglibc and build that one instead? + <pochu> teythoon: put your header in the appropriate /usr/include/ dir + <teythoon> pochu: is there no other way? + <pinotree> iirc nope + <pochu> teythoon: you may be able to pass some flag to configure, but I + don't know if that will work in this specific case + <teythoon> ouch >,< that explains why I haven't found one + <pochu> check ./configure --help, it's usually FOO_CFLAGS (so something + like HURD_CFLAGS maybe) + <pochu> but then you may need _LIBS as well depending on how you changed + the header... so in the end it's just easier to put the header in + /usr/include/ + <braunr> teythoon: did you find the info for your libc build ? + <teythoon> braunr: well, i firmlinked my hurd_types.h into /usr/include/... + <braunr> ew + <braunr> i recommend building debian packages + <teythoon> but the build was not successful, looks unrelated to my changes + though + <teythoon> I tried that last week and the process took more than eight + hours and did not finish + <braunr> use darnassus + <braunr> it takes about 6 hours on it + <teythoon> I shall try again and skip the unused variants + <braunr> i also suggest you use ./debian/rules build + <braunr> and then interrupt the build process one you see it's building + object files + <braunr> go to the hurd-libc-i386 build dir, and use make lib others + <braunr> make lib builds libc, others is for companion libraries lik + libpthread + <braunr> actually building libc takes less than an hour + <braunr> so once you validate your build this way, you know building the + whole debian package will succedd + <braunr> succeed* + <teythoon> so how do I get the build system to pick up my hurd_types.h? + <braunr> sorry if this is obvious to you, you might be more familiar with + debian than i am :) + <braunr> patch the hurd package + <braunr> append your own version string like +teythoon.hurd.1 + <braunr> install it + <braunr> then build libc + <braunr> i'll reboot darnassus so you have a fresh and fast build env + <braunr> almost a month of uptime without any major issue :) + <teythoon> err, but I cannot install my hurd package on darnassus, can I? I + don't think that'd be wise even if it were possible + <braunr> teythoon: rebooted, enjoy + <braunr> why not ? + <braunr> i often do it for my own developments + <braunr> teythoon: screen is normally available + <braunr> teythoon: be aware that fakeroot-tcp is known to hang when pfinet + is out of ports (that's a bug) + <braunr> it takes more time to reach that bug since a patch that got in + less than a year ago, but it still happens + <braunr> the hurd packages are quick to build, and they should only provide + the new header, right ? + <braunr> you can include the functionality too in the packages if you're + confident enough + <teythoon> but my latest work on the killing of essential processes issues + involves patching hurd_types.h and that in a way that breaks the ABI, + hence the need to rebuild the libc (afaiui) + <braunr> teythoon: yes, this isn't uncommon + <teythoon> braunr: this is much more intrusive than anything I've done so + far, so I'm not so confident in my changes for now + <braunr> teythoon: show me the patch please + <teythoon> braunr: it's not split up yet, so kind of messy: + http://paste.debian.net/21403/ + <braunr> teythoon: did you make sure to add RPCs at the end of defs files ? + <teythoon> yes, I got burned by this one on my very first attempt, you + pointed out that mistake + <braunr> :) + <braunr> ok + <braunr> you're changing struct procinfo + <braunr> this really breaks the abi + <teythoon> yes + <braunr> i.e. you can't do that + <teythoon> I cannot put it at the end b/c of that variable length array + <braunr> you probably should add another interface + <teythoon> that'd be easier, sure, but this will slow down procfs even + more, no? + <braunr> that's secondary + <braunr> it won't be easier, breaking the abi may break updates + <braunr> in which case it's impossible + <braunr> another way would be to ues a new procinfo struct + <braunr> like struct procinfo2 + <braunr> but then you need a transition step so that all users switch to + that new version + <braunr> which is the best way to deal with these issues imo, but this time + not the easiest :) + <teythoon> ok, so I'll introduce another rpc and make sure that one is + extensible + <braunr> hum no + <braunr> this usually involves using a version anyway + <teythoon> no? but it is likely that we need to save more addresses of this + kind in the future + <braunr> in which case it will be hanlded as an independant problem with a + true solution such as the one i mentioned + <teythoon> it could return an array of vm_address_ts with a length + indicating how many items were returned + <braunr> it's ugly + <braunr> the code is already confusing enough + <braunr> keep names around for clarity + <teythoon> ok, point taken + <braunr> really, don't mind additional RPCs when first adding new features + <braunr> once the interface is stable, a new and improved version becomes a + new development of its own + <braunr> you're invited to work on that after gsoc :) + <braunr> but during gsoc, it just seems like an unnecessary burden + <teythoon> ok cool, I really like that way of extending Hurd, it's really + easy + <teythoon> and feels so natural + <braunr> i share your concern about performances, and had a similar problem + when adding page cache information to gnumach + <braunr> in the end, i'll have to rework that again + <braunr> because i tried to extend it beyond what i needed + <teythoon> true, I see how that could happen easily + <braunr> the real problem is mig + <braunr> mig limits subsystems to 100 calls + <braunr> it's clearly not enough + <braunr> in x15, i intend to use 16 bits for subsystems and 16 bits for + RPCs, which should be plenty + <teythoon> that limit seems rather artificial, it's not a power of two + <braunr> yes it is + <teythoon> so let's fix it + <braunr> mach had many artificial static limits + <braunr> eh :D + <braunr> not easy + <braunr> replies are encoded by taking the request ID and adding 100 + <teythoon> uh + <braunr> "uh" indeed + <teythoon> so we need an intermediate version of mig that accepts both + id+100 and dunno id+2^x as replies for id + <teythoon> or -id - 1 + <braunr> that would completely break the abi + <teythoon> braunr: how so? the change would be in the *_server functions + and be compatible with the old id scheme + <braunr> how do you make sure id+2^x doesn't conflict with another id ? + <teythoon> oh, the id is added to the subsystem id? + <teythoon> to obtain a global message id? + <braunr> yes + <teythoon> ah, I see + <teythoon> ah, but the hurd subsystems are 1000 ids apart + <teythoon> so id+100 or id +500 would work + <braunr> we need to make sure it's true + <braunr> always true + <teythoon> so how many bits do we have for the message id in mach? + <teythoon> (mig?) + <braunr> mach shouldn't care, it's entirely a mig thing + <braunr> well yes and no + <braunr> mach defines the message header, which includes the message id + <braunr> see mach/message.h + <braunr> mach_msg_id_t msgh_id; + <braunr> typedef integer_t mach_msg_id_t; + <teythoon> well, if that is like a 32 bit integer, then allow -id-1 as + reply and forbid ids > 2^x / 2 + <braunr> yes + <braunr> seems reasonable + <teythoon> that'd give us an smooth upgrade path, no? + <braunr> i think so + + +## IRC, freenode, #hurd, 2013-08-28 + + <youpi> teythoon: Mmm, your patch series does not make e.g. ext2fs provide + a diskfs_get_source, does it? + + +## IRC, freenode, #hurd, 2013-08-29 + + <teythoon> youpi: that is correct + <youpi> teythoon: Mmm, I must be missing something then: as such the patch + series introduces an RPC, but only EOPNOTSUPP is ever returned in all + cases for now? + <youpi> ah + <youpi> /* Guess based on the last argument. */ + <youpi> since ext2fs & such report their options with store last, it seems + ok indeed + <youpi> it still seems a bit lame not to return that information in + get_source + <teythoon> yes + <teythoon> well, if it had been just for me, I would not have created that + rpc, but only guessing was frowned uppon iirc + <teythoon> then again, maybe this should be used and then the mtab + translator could skip any translators that do not provide this + information to filter out non-"filesystem" translators + <youpi> guessing is usually trap-prone, yes + <youpi> if it is to be used by mtab, then maybe it should be documented as + being used by mtab + <youpi> otherwise symlink would set a source, for instance + <youpi> while we don't really want it here + <teythoon> why would the symlink translator answer to such requests? it is + not a filesystem-like translator + <youpi> no, but the name & documentation of the RPC doesn't tell it's only + for filesystem-like translators + <youpi> well, the documentation does say "filesystem" + <youpi> but it does not clearly specify that one shouldn't implement + get_source if one is not a filesystme + <youpi> "If the concept of a source is applicable" works for a symlink + <youpi> that could be the same for eth-filter, etc. + <teythoon> right + <youpi> Mmm, that said it's fsys.defs + <youpi> not io.defs + <youpi> teythoon: it is the fact that we get EOPNOTSUPP (i.e. fsys + interface supported, just not that call), and not MIG_BAD_ID (i.e. fsys + interface not supported), that filters out symlink & such, right? + <teythoon> that's what I was thinking, but that's based on my + interpretation of EOPNOPSUPP of course ;) + <youpi> teythoon: I believe that for whatever is a bit questionable, even + if you put yourself on the side that people will probably agree on, the + discussion will still take place so we make sure it's the right side :) + <youpi> (re: start/end_code) + <teythoon> I'm not sure I follow + <teythoon> youpi: /proc/pid/stat seems to be used a lot: + http://codesearch.debian.net/search?q=%22%2Fproc%2F.*%2Fstat%22 + <teythoon> that does not mean that start/endcode is used, but still it + seems like a good thing to mimic Linux closely + <youpi> stat is used a lot for cpu usage for instance, yes + <youpi> start/endcode, I really wonder who is using it + <youpi> using it for kernel thread detection looks weird to me :) + <youpi> (questionable): I mean that even if you take the time to put + yourself on the side that people will probably agree on, the discussion + will happen + <youpi> it has to happen so people know they agree on it + <youpi> I've seen that a lot in various projects (not only CS-related) + <teythoon> ok, I think I got it + <teythoon> it's to document the reasons for (not) doing something? + <youpi> something like this, yes + <youpi> even if you look right, people will try to poke holes + <youpi> just to make sure :) + <teythoon> btw, I think it's rather unusual that our storeio experiments + would produce such different results + <teythoon> you're right about the block device, no idea why I got a + character file there + <teythoon> I used settrans -ca /tmp/hello.unzipped /hurd/storeio -T + gunzip:file /tmp/hello + <teythoon> also I tried stacking the translator on /tmp/hello directly, + from what I've gathered that should be possible, but I failed + <teythoon> ftr I use the exec server with all my patches, so the unzipping + code has been removed from it + <youpi> ah, I probably still have it + <youpi> it shouldn't matter here, though + <teythoon> I agree + <youpi> how would you stack it? + <youpi> I've never had a look at that + <youpi> I'm not sure attaching the translator to the node is done before or + after the translator has a change to open its target + <teythoon> right + <teythoon> but it could be done, if storeio used the reference to the + underlying node, no? + <youpi> yes + <youpi> btw, you had said at some point that you had issues with running + remap. Was the issue what you fixed with your patches? + * youpi realizes that he should have shown the remap.c source code during + his presentation + <teythoon> well, I tried to remap /servers/exec (iirc) and that failed + <teythoon> then again, I recently played with remap and all seemed fine + <teythoon> but I'm sure it has nothing to do with my patches + <youpi> ok + <teythoon> those I came up with investigating fakeroot-hurd + <teythoon> and I saw that this also aplies to remap.sh + <teythoon> *while + <youpi> yep, they're basically the same + <teythoon> btw, I somehow feel settrans is being abused for chroot and + friends, there is no translator setting involved + <youpi> chroot, the command? or the settrans option? + <youpi> I don't understand what you are pointing at + <teythoon> the settrans option being used by fakeroot, remap and (most + likely) our chroot + <youpi> our chroot is just a file_reparent call + <youpi> fakeroot and remap do start a translator + <teythoon> yes, but it is not being bound to a node, which is (how I + understand it) what settrans does + <teythoon> the point being that if settrans is being invoked with --chroot, + it does something completely different (see the big if (chroot) {...} + blocks) + <teythoon> to a point that it might be better of in a separate command + <youpi> Mmm, indeed, a lot of the options don't make sense for chroot + + +## IRC, freenode, #hurd, 2013-09-06 + + <braunr> teythoon: do you personally prefer /proc being able to implement + /proc/self on its own, or using the magic server to tell clients to + resolve those specific cases themselves ? + <pinotree> imho solving the "who's the sender of an rpc" could solve both + the SCM_CREDS implementation and the self case in procfs + +[[open_issues/SENDMSG_SCM_CREDS]], +[[hurd/translator/procfs/jkoenig/discussion]], *`/proc/self`*. + + <braunr> pinotree: yes + <braunr> but that would require servers impersonating users to some extent + <braunr> and this seems against the hurd philosophy + <pinotree> and there was also the fact that you could create a + fake/different port when sending an rpc + <braunr> to fake what ? + <pinotree> the sender identiy + <pinotree> *identity + <braunr> what ? + <braunr> you mean intermediate servers can do that + <teythoon> braunr: I don't know if I understand all the implications of + your question, but the magic server is the only hurd server that actually + implements fsys_forward (afaics), so why not use that? + <braunr> teythoon: my question was rather about the principle + <braunr> do people find it acceptable to entrust a server with their + authority or not + <braunr> on the hurd, it's clearly wrong + <braunr> but then it means you need special cases everywhere, usually + handled by glibc + <braunr> and that's something i find wrong too + <braunr> it restricts extensibility + <braunr> the user can always change its libc at runtime, but in practice, + it's harder to perform than simply doing it in the server + <teythoon> braunr: then I think I didn't get the question at all + <braunr> teythoon: it's kind of the same issue that you had with the mtab + translator + <braunr> about showing or not some entries the user normally doesn't have + access to + <braunr> this problem occurs when there is more than one server on the + execution path and the servers beyond the first one need credentials to + reply something meaningful + <braunr> the /proc/self case is a perfect one + <braunr> (conceptually, it's client -> procfs -> symlink) + <braunr> 1/ procfs tells the client it needs to handle this specially, + which is what the hurd does with magic + <braunr> 2/ procfs assumes the identity of the client and the symlink + translator can act as expected because of that + <braunr> teythoon: what way do you find better ? + <teythoon> braunr: by "procfs assumes the identity" you mean procfs + impersonating the user? + <braunr> yes + <teythoon> braunr: tbh I still do not see how this can be implemented at + all b/c the /proc/self symlink is not about identity (which can be + derived from the peropen struct initially created by fsys_getroot) but + the pid of the callee (which afaics is nowhere to be found) + <teythoon> s/callee/caller/ + <teythoon> the one doing the rpc + <braunr> impersonating the user isn't only about identity + <braunr> actually, it's impersonating the client + <teythoon> yes, client is the term >,< + <braunr> so basically, asking proc about the properties of the process + being impersonated + <teythoon> proc o_O + <braunr> it's not hard, it's just a big turn in the way the system would + function + <braunr> teythoon: ? + <teythoon> you lost me somewhere + <braunr> the client is the process + <braunr> not the user + <teythoon> in order to implement /proc/self properly, one has to get the + process id of the process doing the /proc/self lookup, right? + <braunr> yes + <braunr> actually, we would even slice it more and have the client be a + thread + <teythoon> so how do you get to that piece of information at all? + <braunr> the server inherits a special port designating the client, which + allows it to query proc about its properties, and assume it's identity in + servers such as auth + <braunr> its* + <teythoon> ah, but that kind of functionality isn't there at the moment, is + it? + <braunr> it's not, by design + <teythoon> right, hence my confusion + <braunr> instead, servers use the magic translator to send a "retry with + special handling" message to clients + <teythoon> right, so the procfs could bounce that back to the libc handler + that of course knows its pid + <braunr> yes + <teythoon> right, so now at last I got the whole question :) + <braunr> :) + <teythoon> ugh, I just found the FS_RETRY_MAGICAL handler in the libc :-/ + <braunr> ? + <braunr> why "ugh" ? + <teythoon> well, I'm inclined to think this is the bad kind of magic ;) + <braunr> do i need to look at the code to understand ? + <teythoon> ok, so I think option 1/ is easily implemented, option 2/ has + consequences that I cannot fully comprehend + <braunr> same for me + <teythoon> no, but you yourself said that you do not like that kind of + logic being implemented in the libc + <braunr> well + <braunr> easily + <braunr> i'm not so sure + <braunr> it's easy to code, but i assume checking for magic replies has its + cost + <teythoon> why not? the code is doing a big switch over the retryname + supplied by the server + <teythoon> we could stuff getpid() logic in there + <braunr> 14:50 < braunr> it's easy to code, but i assume checking for magic + replies has its cost + <teythoon> what kind of cost? computational cost? + <braunr> yes + <braunr> the big switch you mentioned + <braunr> run every time a client gets a reply + <braunr> (unless i'm mistaken) + <teythoon> a only for RETRY_MAGICAL replies + <braunr> but you need to test for it + <teythoon> switch (retryname[0]) + <teythoon> { + <teythoon> case '/': + <teythoon> ... + <teythoon> that should compile to a jump table, so the cost of adding + another case should be minimal, no? + <braunr> yes + <braunr> but + <braunr> it's even less than that + <braunr> the real cost is checking for RETRY_MAGICAL + <braunr> 14:55 < teythoon> a only for RETRY_MAGICAL replies + <braunr> so it's basically a if + <braunr> one if, right ? + <teythoon> no, it's switch'ing over doretry + <teythoon> you should pull up the code and see for yourself. it's in + hurd/lookup-retry.c + <braunr> ok + <braunr> well no, that's not what i'm looking for + <teythoon> it's not o_O + <braunr> i'm looking for what triggers the call to lookup_retry + <braunr> teythoon: hm ok, it's for lookups only, that's decent + <braunr> teythoon: 1/ has the least security implications + <teythoon> yes + <braunr> it could slightly be improved with e.g. a well defined interface + so a user could preload a library to extend it + <teythoon> extend the whole magic lookup thing? + <braunr> yes + <teythoon> but that is no immediate concern, you are trying to fix + /proc/self, right? + <braunr> no, i'm thinking about the big picture for x15/propel, keeping the + current design or doing something else + <teythoon> oh, okay + <braunr> solving /proc/self looks actually very easy + <teythoon> well, I'd say this depends a lot on your trust model then + <teythoon> do you consider servers trusted? + <teythoon> (btw, will there be mutual authentication of clients/servers in + propel?) + <braunr> there were very interesting discussions about that during the + l4hurd project + <braunr> iirc, shapiro insisted that using a server without trusting it + (and there were specific terminology about trusting/relying/etc..) is + nonsense + <braunr> teythoon: i haven't thought too much about that yet, for now it's + supposed to be similar to what the hurd does + <teythoon> hm, then again trust is not an on/off thing imho + <braunr> ? + <teythoon> trusting someone to impersonate yourself is a very high level of + trust + <teythoon> s/is/requires/ + <teythoon> the mobile code paper suggests that mutual authentication might + be a good thing, and I tend to agree + <braunr> i'll have to read that again + <braunr> teythoon: for now (well, when i have time to work on it again + .. :)) + <braunr> i'm focusing on the low level stuff, in a way that won't disturb + such high level features + <braunr> teythoon: have you found something related to a thread-specific + port in the proc server ? + <braunr> hurd/process.defs:297: /* You are not expected to understand + this. */ + <braunr> \o/ + <teythoon> braunr: no, why would I (the thread related question) + <teythoon> braunr: yes, that comment also cought my eye :/ + <braunr> teythoon: because you read a lot of the proc code lately + <braunr> so maybe your view of it is better detailed than mine + + +## IRC, freenode, #hurd, 2013-09-13 + + * youpi crosses fingers + <youpi> yay, still boots + <youpi> teythoon: I'm getting a few spurious entries in /proc/mounts + <youpi> none /servers/socket/26 /hurd/pfinet interface=/dev/eth0, etc. + <youpi> /dev/ttyp0 /dev/ttyp0 /hurd/term name,/dev/ptyp0,type,pty-master 0 + 0 + <youpi> /dev/sd1 /dev/cons ext2fs + writable,no-atime,no-inherit-dir-group,store-type=typed 0 0 + <youpi> fortunately mount drops most of them + <youpi> but not /dev/cons + <youpi> spurious entries in df are getting more and more common on linux + too anyway... + <youpi> ah, after a console restart, I don't have it any more + <youpi> I'm getting df: `/dev/cons': Operation not supported instead + + +## IRC, freenode, #hurd, 2013-09-16 + + <youpi> teythoon: e2fsck does not seem to be seeing that a given filesystem + is mounted + <youpi> /dev/sd0s1 on /boot type ext2 (rw,no-inherit-dir-group) + <youpi> and still # e2fsck -C 0 /dev/sd0s1 + <youpi> e2fsck 1.42.8 (20-Jun-2013) + <youpi> /dev/sd0s1 was not cleanly unmounted, check forced. + <youpi> (yes, both /etc/mtab and /run/mtab point to /proc/mounts) + <tschwinge> Yes, that is a "known" problem. + <youpi> tschwinge: no, it's supposed to be fixed by the mtab translator :) + <pinotree> youpi: glibc's paths.h points to /var/run/mtab (for us) + <tschwinge> youpi: Oh. But this is by means of mtab presence, and not by + proper locking? (Which is at least something, of course!) + <youpi> /var/run points to /run + <youpi> tschwinge: yes + <youpi> anyway, got to run + + +## IRC, freenode, #hurd, 2013-09-20 + + <braunr> teythoon: how come i see three mtab translators running ? + <braunr> 6 now oO + <braunr> looks like df -h spawns a few every time + <teythoon> yes, weird... + <braunr> accessing /proc/mounts does actually + <braunr> teythoon: more bug fixing for you :) + + +## IRC, freenode, #hurd, 2013-09-23 + + <teythoon> so it might be a problem with either libnetfs (which afaics has + never supported passive translator records before) or procfs, but tbh I + haven't investigated this yet + +[[open_issues/libnetfs_passive_translators]]. diff --git a/hurd/translator/netio.mdwn b/hurd/translator/netio.mdwn index 12a3f55c..885b1cc0 100644 --- a/hurd/translator/netio.mdwn +++ b/hurd/translator/netio.mdwn @@ -11,15 +11,16 @@ License|/fdl]]."]]"""]] `netio` is a translator designed for creating socket ports through the filesystem. +This is supposed to be replaced by the better [[socketio]]. + # Source [[source_repositories/incubator]], netio/master -This is supposed to be replaced by the better socketio. # Usage: -e.g. +For example: -cat /tmp/netio/tcp/ftp.gnu.org/21 + $ cat < ~/tmp/netio/tcp/ftp.gnu.org/21 diff --git a/hurd/translator/nsmux.mdwn b/hurd/translator/nsmux.mdwn index d156772b..6b3be79c 100644 --- a/hurd/translator/nsmux.mdwn +++ b/hurd/translator/nsmux.mdwn @@ -1,12 +1,12 @@ -[[!meta copyright="Copyright © 2009 Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2009, 2013 Free Software Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license -is included in the section entitled -[[GNU Free Documentation License|/fdl]]."]]"""]] +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] # nsmux @@ -119,3 +119,24 @@ of the simplest use-case of namespace-based translator selection in the form of translator `nsmux`. The filter is partially implemented and this is the immediate goal. Propagating translators down directories is the next objective. + + +## Open Issues + +### IRC, freenode, #hurd, 2013-08-22 + +[[!tag open_issue_hurd]] + + < youpi> err, is nsmux supposed to work at all? + < youpi> a mere ls doesn't work + < youpi> I'm running it as a user + < youpi> echo * does work though + < teythoon> ah, yes, nsmux,,is,,funny :p + < youpi> well, perhaps but I can't make it work + < youpi> well, the trivial ,,hello does work + < youpi> but ,,tarfs doesn't seem to be working for instance + < youpi> same for ,,mboxfs + < youpi> ,,xmlfs seems to somehow work a bit, but not very far... + < youpi> so it seems just nobody is caring about putting READMEs wherever + appropriate + < youpi> e.g. examples in socketio/ ... diff --git a/hurd/translator/pfinet.mdwn b/hurd/translator/pfinet.mdwn index f6f69ea4..bf535b21 100644 --- a/hurd/translator/pfinet.mdwn +++ b/hurd/translator/pfinet.mdwn @@ -1,5 +1,5 @@ -[[!meta copyright="Copyright © 2002, 2004, 2005, 2007, 2008, 2011 Free Software -Foundation, Inc."]] +[[!meta copyright="Copyright © 2002, 2004, 2005, 2007, 2008, 2011, 2013 Free +Software Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this @@ -33,6 +33,9 @@ installation. * [[DHCP]]. + * [[IPv6]]. + + * [[eth-filter]]: Firewall. + * [[Implementation]]. - * [[IPv6]]. diff --git a/hurd/translator/pfinet/implementation.mdwn b/hurd/translator/pfinet/implementation.mdwn index 9bcf62ef..3e66c870 100644 --- a/hurd/translator/pfinet/implementation.mdwn +++ b/hurd/translator/pfinet/implementation.mdwn @@ -27,6 +27,170 @@ implementation. <youpi> oh <braunr> http://jl-icase.home.comcast.net/~jl-icase/LinuxTCP2.html +## IRC, freenode, #hurd, 2013-09-03 + +In context of the item on [[/contributing]]. + + <rekado> About this task: "Make pfinet OK with the ethernet device going + away." --- how can I test this? How can I remove the ethernet device? + <pinotree> settrans on the ethernet device, handled by the netdde + translator + <pinotree> that is, make it go away (settrans -fg) + <rekado> Ah, I see. + <rekado> Thanks + <pinotree> check its status before with showtrans + <pinotree> then, after having made it go away, set it again + <rekado> I don't think I'm doing this right... After `settrans -fg + /dev/eth0` I should not be able to access the network anymore, but it + still works. + <rekado> How can I figure out which of the four network devices is actually + used? + <braunr> rekado: the file system is used to open files, i.e. access + services + <braunr> it's not used to revoke access + <braunr> once pfinet has obtained a port to the network device, it keeps it + <rekado> oh, yes, of course. Sorry, this is all very + [1;5C[1;5C[1;5C[1;5Cnew to me. + <rekado> I'm not sure what the problem is that this task describes. In + what way is pfinet "not OK" with the ethernet device going away? + <braunr> rekado: the idea is to make pfinet able to cope with a driver + crash + <rekado> Can I trigger a driver crash for test purposes? (Or do I have to + build a purposefully broken driver first?) + <braunr> use kill + <rekado> Oh, good. + <braunr> iirc, netdde doesn't restart correctly :x + <braunr> you'll probably have to fix it a bit + <braunr> i guess there is some persistent state that prevents it from + reinitializing correctly + <rekado> okay + <rekado> I may need one more pointer: where can I find the netdde code? + Grep'ing around I only see it only mentioned as an argument to + /hurd/devnode; also: should I work in some incubator branch or directly + in the hurd repo? + <braunr> rekado: incubator branch + <rekado> Okay. Thank you for your patience. I'll play with this in the + next few days. + <braunr> enjoy + <rekado> :) + + +### IRC, freenode, #hurd, 2013-09-05 + + <rekado> When I kill the /hurd/netdde process I can no longer access the + network (as expected); + <rekado> To restore connectivity I run "settrans -g eth0 /hurd/devnode -M + /dev/netdde eth0" from the /dev directory. + <rekado> When I access the network again everything is fine. (I do see a + message telling me "irq handler 11: release an dead delivery port" + <rekado> ) + <rekado> Is it the goal to avoid having to run settrans again to run netdde + after it crashes or is killed? + <youpi> you don't need to run settrans again + <youpi> that should get triggered automatically + <rekado> Hmm, after killing netdde I get "Resource lost" when using wget. + <rekado> It doesn't seem to be restarted automatically. + <youpi> try again + <youpi> the first wget makes pfinet try to use netdde and fail, thus crash + <youpi> the second wil respawn pfinet + <youpi> ideally pfinet shouldn't die, that's a TODO mentioned in the + "contributing page" + <rekado> Ah, so that's what should be prevented. + <youpi> it's just a matter of making pfinet be fine with errors from the + eth translator, and simply reopen it instead of dying + <rekado> That's the thing I've been trying to figure out. + <rekado> when I run wget a second (or third) time I get a different error; + "Name or service not known." + <rekado> It's only okay again when I use settrans + <youpi> maybe the devnode translator also needs some fixing + <youpi> it's odd that I don't have the issue though + <rekado> I'm using the qemu image, updated just yesterday. + <youpi> same here + <youpi> anyway, now you know where to put your hands :) + <rekado> yes, thanks a lot. + + +### IRC, freenode, #hurd, 2013-09-07 + + <rekado> in pfinet/ethernet.c:ethernet_open there's an assertion: + edev->ether_port == MACH_PORT_NULL + <rekado> This is violated when netdde was killed and the device is + reopened. + <rekado> I'm not sure what should be done: destroy the port before + reopening or drop the assertion? + <rekado> If I drop the assertion, Mach seems to handle this just fine. + <rekado> Says "irq handler 11: release an [sic] dead delivery port" and + then carries on without problems. + <rekado> Is this a warning or an error, or can this be ignored? + <rekado> (or none of the above?) + + +### IRC, freenode, #hurd, 2013-09-08 + + <rekado> I have a simple patch for pfinet that lets it recover from an + error in ethernet_xmit when /hurd/netdde and /hurd/devnode have been + killed. + <rekado> It doesn't work, though, when only netdde has been killed. + <rekado> With devnode still around device_open fails with "(ipc/send) + invalid destination port" + <rekado> I don't know where device_open is defined and why this error is + returned. + <rekado> I guess the error refers to the "master_device" port returned by + file_name_lookup() in ethernet_open() + <rekado> Why would file_name_lookup() return an invalid port when netdde is + dead but devnode is still running? + <braunr> rekado: maybe because devnode needs to perform a fresh lookup as + well + + +### IRC, freenode, #hurd, 2013-09-09 + + <rekado> braunr: re devnode: devnode only performs a single lookup in + parse_opt(), i.e. at start-up. + <rekado> I'll try to understand devnode enough to patch it. + <braunr> rekado: that's the problem + <braunr> it should perform a lookup every time it's opened + +[[!message-id "1378730237-8091-1-git-send-email-rekado@elephly.net"]], +[[!message-id "1378731824-8928-1-git-send-email-rekado@elephly.net"]]. + + <rekado> I submitted two patches to the mailing list. I've tested them on + Debian GNU/Hurd but based them on the incubator/dde branch. + <teythoon> rekado: awesome, reliability fixes are very much welcome + + +### IRC, freenode, #hurd, 2013-09-18 + + <rekado> youpi: my apologies for the delay in getting back to you with + improvements to my pfinet/devnode patches. Been very busy. + <braunr> rekado: development pace on the hurd has always been slow, no need + to apologize + +## MAC Addresses + +[[!tag open_issue_hurd]] + + +### IRC, freenode, #hurd, 2013-09-21 + + <jproulx> what command will show me the MAC address of an interface? + <youpi> ah, too bad inetutils-ifconfig doesn't seem to be showing it + <youpi> I don't think we already have a tool for that + <youpi> it would be a matter of patching inetutils-ifconfig + + +## Routing Tables + +[[!tag open_issue_hurd]] + + +### IRC, freenode, #hurd, 2013-09-21 + + <jproulx> Hmmm, OK I can work around that, what about routing tables, can I + see them? can I add routes besides the pfinet -g default route? + <youpi> I don't think there is a tool for that yet + <youpi> it's not plugged inside pfinet anyway + # Reimplementation, [[!GNU_Savannah_task 5469]] @@ -58,3 +222,6 @@ implementation. <youpi> I used it for the stubdomains in Xen <youpi> (it = lwip) <braunr> ok + +Cloudius OSv apparently have isolated/re-used a BSD networking stack, +<http://www.osv.io/>, <https://github.com/cloudius-systems/osv>. diff --git a/hurd/translator/pflocal.mdwn b/hurd/translator/pflocal.mdwn index dc2434dc..fdcc39f1 100644 --- a/hurd/translator/pflocal.mdwn +++ b/hurd/translator/pflocal.mdwn @@ -1,13 +1,35 @@ -[[!meta copyright="Copyright © 2000, 2008 Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2000, 2008, 2013 Free Software Foundation, +Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license -is included in the section entitled -[[GNU Free Documentation License|/fdl]]."]]"""]] +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] The implementation of the `pflocal` server is in the `pflocal` directory, and uses [[`libpipe`|libpipe]] (shared code with the [[named_pipe|fifo]] implementation). + + +# Open Issues + +## `SO_REUSEADDR` + +### IRC, freenode, #hurd, 2013-09-19 + + <gnu_srs> Hi, is SO_REUSEADDR supported at all on Hurd? I can only find two + entries: + <gnu_srs> in libdde-linux26 and pfinet/linux-src, and the functionality + seems to be unimplemented. + <pinotree> gnu_srs: pfinet supports it + <youpi> gnu_srs: grep talks about pfinet/linux-src/net/core/sock.c: + case SO_REUSEADDR: + <youpi> two times + <gnu_srs> Yes, and that is the implementation? + <gnu_srs> I wrote a test for AF_INET and it works, but not for AF_UNIX + (maybe not so interesting case). + <pinotree> pflocal does not support it + <gnu_srs> Is that of interest at all? diff --git a/hurd/translator/proc.mdwn b/hurd/translator/proc.mdwn new file mode 100644 index 00000000..d5e0960c --- /dev/null +++ b/hurd/translator/proc.mdwn @@ -0,0 +1,75 @@ +[[!meta copyright="Copyright © 2012, 2013 Free Software Foundation, Inc."]] + +[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable +id="license" text="Permission is granted to copy, distribute and/or modify this +document under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no Invariant +Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] + +The *proc server* (or, *process server*) implements some aspects of [[Unix]] +processes. + +It is stated by `/hurd/init`. + + +# "Unusual" PIDs + +[[!tag open_issue_hurd]] + + +## IRC, freenode, #hurd, 2012-08-10 + + <braunr> too bad the proc server has pid 0 + <braunr> top & co won't show it + + +## IRC, OFTC, #debian-hurd, 2012-09-18 + + <pinotree> youpi: did you see + https://enc.com.au/2012/09/careful-with-pids/' + <pinotree> ? + <youpi> nope + + +## IRC, OFTC, #debian-hurd, 2013-06-23 + + <teythoon> I've got this idea about the pid 1 issue you mentioned + <teythoon> can't we just make init pid 1? + <teythoon> I mean the mapping is rather arbitrary, we could make our init + pid 2 or something and start sysvs init as pid 1 + <pinotree> not totally sure it is that arbitrary up to the first 4-5 pids + <teythoon> y is that? + <pinotree> at least i see in hurd's code that /hurd/init is assumed as + pid=1 + <teythoon> hurds init that has to stick around for the fs translator sync? + <pinotree> hurd's init does the basic server startup + <pinotree> iirc it also takes care of shutdown/reboot + <teythoon> that's what I meant + <teythoon> and if it wouldn't have to stick around for the translator sync + it could just exec sysvinit + <teythoon> I just think it's easier to patch hurd than to remove the + assumption that init is pid 1 from sysvinit + + +## IRC, freenode, #hurd, 2013-09-13 + + <braunr> teythoon: also, as a feature request, i'd like the proc server not + to have pid 0, if you have any time to do that + <braunr> so it appears in top and friends + <teythoon> braunr: noted, that should be easy + <teythoon> not using 0 is probably a good thing, many things use pid 0 as + something special + + +# Process Discovery + +## IRC, freenode, #hurd, 2013-08-26 + + < teythoon> somewhat related, I do not like the way the proc server just + creates processes for new mach tasks it discovers + < teythoon> that does not play well with subhurds for example + < braunr> teythoon: i agree with you on proc process-to-task mapping + < braunr> that's something i intend to completely rework on propel + < braunr> in a way similar to how pid namespaces work on linux diff --git a/hurd/translator/procfs/jkoenig/discussion.mdwn b/hurd/translator/procfs/jkoenig/discussion.mdwn index b5517b90..fc071337 100644 --- a/hurd/translator/procfs/jkoenig/discussion.mdwn +++ b/hurd/translator/procfs/jkoenig/discussion.mdwn @@ -14,12 +14,13 @@ License|/fdl]]."]]"""]] [[!toc]] -# Miscellaneous +# `/proc/version` -IRC, #hurd, around September 2010 +[[!taglink open_issue_documentation]]: edit and move to [[FAQ]]. + + +## IRC, freenode, #hurd, around 2010-09 - <youpi> jkoenig: is it not possible to provide a /proc/self which points at - the client's pid? <pinotree> (also, shouldn't /proc/version say something else than "Linux"?) <youpi> to make linux tools work, no :/ <youpi> kfreebsd does that too @@ -33,10 +34,103 @@ IRC, #hurd, around September 2010 <youpi> Linux version 2.6.16 (des@freebsd.org) (gcc version 4.3.5) #4 Sun Dec 18 04:30:00 CET 1977 <pinotree> k - <giselher> I had some problems with killall5 to read the pid from /proc, Is - this now more reliable? - <youpi> I haven't tested with jkoenig's implementation - [...] + + +## IRC, freenode, #hurd, 2013-06-04 + + <safinaskar> ?@?#@?$?@#???!?!?!?!??!?!?!?! why /proc/version on gnu system + reports "Linux version 2.6.1 (GNU 0.3...)"? + <braunr> safinaskar: because /proc/version is a linux thing + <braunr> applications using it don't expect to see anything else than linux + when parsing + <braunr> think of it as your web brower allowing you to set the user-agent + <safinaskar> braunr: yes, i just thought about user-agent, too + <safinaskar> braunr: but freebsd doesn't report it is linux (as well as i + know) + <braunr> their choice + <braunr> we could change it, but frankly, we don't care + <safinaskar> so why "uname" says "GNU" and not "Linux"? + <braunr> uname is posix + <braunr> note that /proc/version also includes GNU and GNU Mach/Hurd + versions + <safinaskar> if some program read the word "Linux" from /proc/version, it + will assume it is linux. so, i think it is bad idea + <braunr> why ? + <safinaskar> there is no standard /proc across unixen + <braunr> if a program reads /proc/version, it expects to be run on linux + <safinaskar> every unix implement his own /proc + <safinaskar> so, we don't need to create /proc which is fully compatible + with linux + <braunr> procfs doesn't by default + <safinaskar> instead, we can make /proc, which is partially compatible with + linux + <braunr> debiansets the -c compatibility flag + <braunr> that's what we did + <safinaskar> but /proc/version should really report kernel name and its + version + <braunr> why ? + <braunr> (and again, it does) + <safinaskar> because this is why /proc/version created + <pinotree> no? + <braunr> on linux, yes + <braunr> pinotree: hm ? + <safinaskar> and /proc/version should not contain the "Linux" word, because + this is not Linux + <braunr> pinotree: no to what ? :) + <braunr> safinaskar: *sigh* + <braunr> i explained the choice to you + <pinotree> safinaskar: if you are using /proc/version to get the kernel + name and version, you're doing bad already + <braunr> disagree if you want + <braunr> but there is a point to using the word Linux there + <pinotree> safinaskar: there's the proper aposix api for that, which is + uname + <safinaskar> pinotree: okey. so why we ever implement /proc/version? + <braunr> it's a linux thing + <braunr> they probably wanted more than what the posix api was intended to + do + <safinaskar> okey, so why we need this linux thing? there is a lot of + linux thing which is useful in hurd. but not this thing. because this + is not linux. if we support /proc/version, we should not write "Linux" + to it + <pinotree> and even on freebsd their linprocfs (mounted on /proc) is not + mounted by default + <braunr> 10:37 < braunr> applications using it don't expect to see anything + else than linux when parsing + <braunr> 10:37 < braunr> think of it as your web brower allowing you to set + the user-agent + <braunr> safinaskar: the answer hasn't changed + <safinaskar> pinotree: but they don't export /proc/version with "Linux" + word in it anyway + <pinotree> safinaskar: they do + <safinaskar> pinotree: ??? their /proc/version contain Linux? + <pinotree> Linux version 2.6.16 (des@freebsd.org) (gcc version 4.6.3) #4 + Sun Dec 18 04:30:00 CET 1977 + <kilobug> safinaskar: it's like all web browsers reporting "mozilla" in + their UA, it may be silly, but it's how it is for + compatibility/historical reasons, and it's just not worth the trouble of + changing it + <pinotree> that's on a debian gnu/kfreebsd machine + <pinotree> and on a freebsd machine it is the same + <braunr> safinaskar: you should understand that parsing this string allows + correctly walking the rest of the /proc tree + <pinotree> and given such filesystem on freebsd is called "linprocfs", you + can already have a guess what it is for + <kilobug> safinaskar: saying "Linux version 2.6.1" just means "I'm + compatible with Linux 2.6.1 interfaces", like saying "Mozilla/5.0 (like + Gecko)" in the UA means "I'm a modern browser" + <safinaskar> so, is there really a lot of programs which expect "Linux" + word in /proc/version even on non-linux platforms? + <braunr> no + <braunr> but when they do, they do + + +# `/proc/self` + +## IRC, freenode, #hurd, around 2010-09 + + <youpi> jkoenig: is it not possible to provide a /proc/self which points at + the client's pid? <pinotree> looks like he did 'self' too, see rootdir_entries[] in rootdir.c <youpi> but it doesn't point at self <antrik> youpi: there is no way to provide /proc/self, because the server @@ -56,10 +150,12 @@ IRC, #hurd, around September 2010 <youpi> it "just" needs to be commited :) <antrik> in either case, it can't hurt to bring this up again :-) +[[mtab/discussion]], *IRC, freenode, #hurd, 2013-09-07*. + # root group -IRC, #hurd, around October 2010 +## IRC, freenode, #hurd, around October 2010 <pinotree> the only glitch is that files/dirs have the right user as owner, but always with root group @@ -67,7 +163,7 @@ IRC, #hurd, around October 2010 # `/proc/[PID]/stat` being 400 and not 444, and some more -IRC, freenode, #hurd, 2011-03-27 +## IRC, freenode, #hurd, 2011-03-27 <pochu> is there a reason for /proc/$pid/stat to be 400 and not 444 like on Linux? @@ -112,7 +208,8 @@ IRC, freenode, #hurd, 2011-03-27 /proc uses rather than rely on CLK_TCK <jkoenig> (so we can choose whatever reasonable value we want) -IRC, freenode, #hurd, 2011-03-28 + +## IRC, freenode, #hurd, 2011-03-28 <antrik> jkoenig: does procfs expose any information that is not available to everyone through the proc server?... @@ -165,7 +262,8 @@ IRC, freenode, #hurd, 2011-03-28 <antrik> (though I never got around to look at his buggy code...) <jkoenig> ok -IRC, freenode, #hurd, 2011-07-22 + +## IRC, freenode, #hurd, 2011-07-22 <pinotree> hm, why /proc/$pid/stat is 600 instead of 644 of linux? <jkoenig> pinotree, it reveals information which, while not that sensitive, @@ -186,7 +284,7 @@ IRC, freenode, #hurd, 2011-07-22 # `/proc/mounts`, `/proc/[PID]/mounts` -IRC, freenode, #hurd, 2011-07-25 +## IRC, freenode, #hurd, 2011-07-25 < pinotree> jkoenig: btw, what do you think about providing empty /proc/mounts and /proc/$pid/mounts files? @@ -209,16 +307,31 @@ IRC, freenode, #hurd, 2011-07-25 A [[mtab]] translator now exists. -# `/proc/[PID]/auxv`, `/proc/[PID]/exe`, `/proc/[PID]/mem` +## IRC, freenode, #hurd, 2013-09-20 + + <pinotree> teythoon: should procfs now have $pid/mounts files pointing to + ../mounts? + <teythoon> pinotree: probably yes + + +# `/proc/[PID]/auxv` + +Needed by glibc's `pldd` tool (commit +11988f8f9656042c3dfd9002ac85dff33173b9bd). + + +# `/proc/[PID]/exe` Needed by glibc's `pldd` tool (commit 11988f8f9656042c3dfd9002ac85dff33173b9bd). -# `/proc/self/exe` +## `/proc/self/exe` [[!message-id "alpine.LFD.2.02.1110111111260.2016@akari"]]. Needed by glibc's `stdlib/tst-secure-getenv.c`. +`HAVE_PROC_SELF_EXE` in `[GCC]/libjava/configure.ac`. +Also used in `[GCC]/libgfortran/runtime/main.c`:`store_exe_path`. Is it generally possible to use something like the following instead? Disadvantage is that every program using this needs to be patched. @@ -316,32 +429,25 @@ This is used in `[LLVM]/lib/Support/Unix/Path.inc`. report why the test suite failed -# `/proc/[PID]/cwd` +## `/proc/self/maps` -## IRC, freenode, #hurd, 2012-06-30 - - * pinotree has a local work to add the /proc/$pid/cwd symlink, but relying - on "internal" (but exported) glibc functions +`HAVE_PROC_SELF_MAPS` in `[GCC]/libjava/configure.ac`. +Also used in `[GCC]/intl/relocatable.c`:`find_shared_library_fullname` for +`#ifdef __linux__`. -# "Unusual" PIDs +# `/proc/[PID]/mem` -Not actually related to procfs, but here seems to be a convenient place for -filing these: - - -## IRC, freenode, #hurd, 2012-08-10 +Needed by glibc's `pldd` tool (commit +11988f8f9656042c3dfd9002ac85dff33173b9bd). - <braunr> too bad the proc server has pid 0 - <braunr> top & co won't show it +# `/proc/[PID]/cwd` -## IRC, OFTC, #debian-hurd, 2012-09-18 +## IRC, freenode, #hurd, 2012-06-30 - <pinotree> youpi: did you see - https://enc.com.au/2012/09/careful-with-pids/' - <pinotree> ? - <youpi> nope + * pinotree has a local work to add the /proc/$pid/cwd symlink, but relying + on "internal" (but exported) glibc functions # CPU Usage diff --git a/hurd/translator/socketio.mdwn b/hurd/translator/socketio.mdwn index 99a28416..de5cf252 100644 --- a/hurd/translator/socketio.mdwn +++ b/hurd/translator/socketio.mdwn @@ -11,15 +11,36 @@ License|/fdl]]."]]"""]] `socketio` is a translator designed for creating socket ports through the filesystem. +This is supposed to replace [[netio]]. + # Source [[source_repositories/incubator]], socketio/master -This is supposed to replace netio. # Usage: -e.g. +For example: + + $ cat < ~/tmp/socketio/tcp/ftp.gnu.org/21 + + +# Open Issues + +## IRC, freenode, #hurd, 2013-06-30 + +[[!tag open_issue_hurd]] -cat /tmp/socketio/tcp/ftp.gnu.org/21 + <youpi> http://lists.gnu.org/archive/html/bug-hurd/2003-05/msg00069.html + <youpi> this was supposed to be much better than our current netio + <youpi> (which doesn't really have any documentation btw) + <teythoon> + http://web.archive.org/web/20060117085538/http://duesseldorf.ccc.de/~moritz/files/socketio.c.gz + <teythoon> youpi: socketio looks nice. any reason in particular why you are + working on it? + <youpi> teythoon: I was looking at the firewall stuff, and wondering about + Zheng Da's work, and seen netio, thus wondered "what is it about + already?" and found there was no documentation, so dug into the mailing + list archives, only to find it was supposed to be precated in favour of + socketio, etc. :) diff --git a/hurd/translator/tmpfs/tmpfs_vs_defpager.mdwn b/hurd/translator/tmpfs/tmpfs_vs_defpager.mdwn index 5228515f..16a23405 100644 --- a/hurd/translator/tmpfs/tmpfs_vs_defpager.mdwn +++ b/hurd/translator/tmpfs/tmpfs_vs_defpager.mdwn @@ -1,4 +1,5 @@ -[[!meta copyright="Copyright © 2010, 2011 Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2010, 2011, 2013 Free Software Foundation, +Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this @@ -270,3 +271,129 @@ See also: [[open_issues/resource_management_problems/pagers]]. <antrik> only problem is that the current defpager implementation can't really handle that... <antrik> at least that's my understanding of the situation + + +# IRC, freenode, #hurd, 2013-07-05 + + <teythoon> btw, why does the tmpfs translator have to talk to the pager? + <teythoon> to get more control about how the memory is paged out? + <teythoon> read lot's of irc logs about tmpfs on the wiki, but I couldn't + find the answer to that + <mcsim> teythoon: did you read this? + http://www.gnu.org/software/hurd/hurd/translator/tmpfs/tmpfs_vs_defpager.html + <teythoon> mcsim: I did + <mcsim> teythoon: Last discussion, i think has very good point. + <mcsim> To provide memory objects you should implement pager interface + <mcsim> And if you implement pager interface you are the one who is asked + to write data to backing storage to evict them + <mcsim> But tmpfs doesn't do this + <teythoon> mmm, clients doing mmap... + <mcsim> teythoon: You don't have mmap + <mcsim> teythoon: mmap is implemented on top of mach interface + <mcsim> teythoon: I mean you don't have mmap at this level + <teythoon> mcsim: sure, but that's close enough for me at this point + <mcsim> teythoon: diskfs interface requires implementor to provide a memory + object port (send right) + <mcsim> Guest8183: Why tmpfs requires defpager + <Guest8183> how did you get to talk about that ? + <mcsim> I was just asked + <teythoon> Guest8183: it's just so unsettling that tmpfs has to be started + as root :/ + <Guest8183> teythoon: why ? + *** Guest8183 (~rbraun@dalaran.sceen.net) is now known as braunr_ + <teythoon> braunr_: b/c starting translators isn't a privileged operation, + and starting a tmpfs translator that doesn't even access any device but + "just" memory shouldn't require any special privileges as well imho + <teythoon> so why is tmpfs not based on say libnetfs? b/c it is used for + d-i and someone (apt?) mmaps stuff? + <pinotree> being libdiskfs-based isn't much the issue, iirc + <pinotree> http://lists.gnu.org/archive/html/bug-hurd/2013-03/msg00014.html + too + <kilobug> teythoon: AFAIK apt uses mmap, yes + <braunr_> teythoon: right + <braunr_> a ramfs is actually tricky to implement well + <mcsim> braunr_: What do you mean under "to implement well"? + <braunr_> as efficiently as possible + <braunr_> i.e. being as close as possible to the page cache for minimum + overhead + <mcsim> braunr: AFAIK ramfs should not use swap partition, so page cache + shouldn't be relevant for it. + <braunr> i'm talking about a ramfs in general + <braunr> not the specific linux ramfs + <braunr> in linux, what they call ramfs is the tiny version of tmpfs that + doesn't use swap + <braunr> i actually don't like "tmpfs" much + <braunr> memfs may be more appropriate + <braunr> anyway + <mcsim> braunr: I see. And do you consider defpager variant as "close as + possible to the page cache"? + <braunr> not far at least + <braunr> if we were able to use it for memory obects, it would be nice + <braunr> but defpager only gets attached to objects when they're evicted + <braunr> before that, anonymous (or temporary, in mach terminology) objects + have no backing store + <braunr> this was probably designed without having tmpfs in mind + <braunr> i wonder if it's possible to create a memory object without a + backing store + <mcsim> what should happen to it if kernel decides to evict it? + <braunr> it sets the default pager as its backing store and pushes it out + <mcsim> that's how it works now, but you said "create a memory object + without a backing store" + <braunr> mach can do that + <braunr> i was wondering if we could do that too from userspace + <mcsim> mach does not evict such objects, unless it bound a defpager to + them + <mcsim> but how can you handle this in userspace? + <braunr> i mean, create a memory object with a null control port + <braunr> mcsim: is that clearer ? + <mcsim> suppose you create such object, how kernel will evict it if kernel + does not know who is responsible for eviction of this object? + <braunr> it does + <braunr> 16:41 < braunr> it sets the default pager as its backing store and + pushes it out + <braunr> that's how i intend to do it on x15 at least + <braunr> but it's much simpler there because uvm provides better separation + between anonymous and file memory + <braunr> whereas they're much too similar in mach vm + <mcsim> than what the difference between current situation, when you + explicitly invoke defpager to create object and implicit method you + propose? + <braunr> you don't need a true defpager unless you actually have swap + <mcsim> ok + <mcsim> now I see + <braunr> it also saves the communication overhead when initializing the + object + <mcsim> thank you + <braunr> which may be important since we use ramfs for speed mostly + <mcsim> agree + <braunr> it should also simplify the defpager implementation, since it + would only have a single client, the kernel + <braunr> which may also be important with regard to global design + <braunr> one thing which is in my opinion very wrong with mach is that it + may be a client + <braunr> a well designed distributed system should normally not allow on + component to act as both client and server toward another + <braunr> i.e. the kernel should only be a server, not a client + <braunr> and there should be a well designed server hierarchy to avoid + deadlocks + <braunr> (such as the one we had in libpager because of that) + <mcsim> And how about filesystem? It acts both as server and as client + <braunr> yes + <braunr> but not towards the same other component + <braunr> application -> file system -> kernel + <braunr> no "<->" + <braunr> the qnx documentation explains that quite well + <braunr> let me see if i can find the related description + <mcsim> Basically, I've got your point. And I would rather agree that + kernel should not act as client + <braunr> mcsim: + http://www.qnx.com/developers/docs/6.4.0/neutrino/sys_arch/ipc.html#Robust + <braunr> one way to implement that (and qnx does that too) is to make + pagers act as client only + <braunr> they sleep in the kernel, waiting for a reply + <braunr> and when the kernel needs to evict something, a reply is sent + <braunr> (qnx doesn't actually do that for paging, but it's a general idea) + <mcsim> braunr: how hierarchy of senders is enforced? + <braunr> it's not + <braunr> developers must take care + <braunr> same as locking, be careful about it diff --git a/hurd/translator/ufs.mdwn b/hurd/translator/ufs.mdwn new file mode 100644 index 00000000..4d611e95 --- /dev/null +++ b/hurd/translator/ufs.mdwn @@ -0,0 +1,38 @@ +[[!meta copyright="Copyright © 2013 Free Software Foundation, Inc."]] + +[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable +id="license" text="Permission is granted to copy, distribute and/or modify this +document under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no Invariant +Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] + +The `ufs` translator supports some kind of the Unix File System. Beware, we're +not aware of anybody having used/tested it in ages, so maybe it is very broken +and will eat your data. + + +# IRC, freenode, #hurd, 2013-08-30 + +[[!tag open_issue_hurd]] + + <Arne`> There might be a copyright problem: <nalaginrut> well, there seems + BSD-4clauses in the code: + http://git.savannah.gnu.org/cgit/hurd/hurd.git/tree/ufs/alloc.c + <Arne`> braunr, tschwinge: Do you have any info on that? 4-clause BSD and + GPL on the same code are a license incompatibility… + <tschwinge> Arne`: I've put it onto my (long) TODO list. + <tschwinge> Easiest solution might be: rm -rf ufs. + <nalaginrut> will these affected code rewritten? or just modify license? + <mark_weaver> only the regents of the University of California could choose + to modify the license. + <youpi> nalaginrut: one can't modify a licence if one is not the author + <youpi> we can simply dump the code + <mark_weaver> s/author/owner/ + <tschwinge> As I suppose ufs is unused/untested for a decade or so, I'd + have no issues with simply removing it from the tree, together with + ufs-fsck and ufs-utils. + <pinotree> tschwinge: or maybe extract the ufs stuff in an own repo, to be + imported as branch in incubator or own hurd/ufs.git? + <tschwinge> Sure, why not. |