From 06b13cd7d45923b1f08d939935f1c213416186ef Mon Sep 17 00:00:00 2001 From: Thomas Schwinge Date: Wed, 30 Nov 2011 16:54:25 +0100 Subject: open_issues/glibc/t/t-tls -> open_issues/glibc/t/tls. --- open_issues/glibc/t/t-tls.mdwn | 66 ------------------------------------------ open_issues/glibc/t/tls.mdwn | 66 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 66 insertions(+), 66 deletions(-) delete mode 100644 open_issues/glibc/t/t-tls.mdwn create mode 100644 open_issues/glibc/t/tls.mdwn (limited to 'open_issues/glibc') diff --git a/open_issues/glibc/t/t-tls.mdwn b/open_issues/glibc/t/t-tls.mdwn deleted file mode 100644 index 14ef36e4..00000000 --- a/open_issues/glibc/t/t-tls.mdwn +++ /dev/null @@ -1,66 +0,0 @@ -[[!meta copyright="Copyright © 2011 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_glibc open_issue_libpthread]] - -# To Do - - * Discuss d2431f633e6139a62e1575ec18830f7e81160cf0 with Samuel. - - * `TLS_INIT_TP_EXPENSIVE` is unused; Hurd def. can be removed. - - -# Documentation - -[[!taglink open_issue_documentation]] - - * IRC, freenode, #hurd, 2011-11-26 - - In glibc multiarch support (strcasecmp for i686 SSE3, etc.) - there is access to memory via gs: -- this will need to be changed for - us, right? - depends on the access - * `optimized strcasecmp and strncasecmp for x86-32` - (multiarch), - 76e3966e9efc3808a9e7ad09121c5dfc1211c20b + - 6abf346582ba678f4850a88b4a5950593841df1d + - 5583a0862cf94f71cbcde91c4043a20af65facca. `gs` - access. - + movl __libc_tsd_LOCALE@GOTNTPOFF(%ebx), %eax - that's handled by the linker fine - it's only the things held in the tcb_t structure which can pose - problem - tcbhead_t? - I'm looking at this. - So, at gs:0, there is the TCB. - And we have the same layout as NPTL/Linux, just that we - don't have as much data there as they have. - We're missing multiple_threads, sysinfo, sttack_guard, - pointer_guard, gscope_flag, private_futex, __private_tm[5]. - So, if one of these is referenced (be it my name or by - numeric offset), this is invalid for us. - Anything else should work equivalently. - yes - usually the only numeric offset being used is 0 - so it would simply not build - And the other offsers are generated via tcb-offsets.sym. - glibc's elf/stackguard-macros.h is wrong for us (but not - used anywhere apart from elf/tst-stackguard1.c, I think). - __thread __locale_t __libc_tsd_LOCALE = &_nl_global_locale; - -- this means that a __libc_tsd_LOCALE values will be in the TLS - segment, and this is what is being accessed from the assembler code - with %gs:__libc_tsd_LOCALE@NTPOFF, and the linker will resolve this. - yes - see in the nm output, the libc_tsd symbols - these provide the offsets - youpi: Thank you, I'm now understanding this part of TLS - much better. - have you had a look at the tls.pdf from Uli ? - all the gory details are there :) diff --git a/open_issues/glibc/t/tls.mdwn b/open_issues/glibc/t/tls.mdwn new file mode 100644 index 00000000..14ef36e4 --- /dev/null +++ b/open_issues/glibc/t/tls.mdwn @@ -0,0 +1,66 @@ +[[!meta copyright="Copyright © 2011 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_glibc open_issue_libpthread]] + +# To Do + + * Discuss d2431f633e6139a62e1575ec18830f7e81160cf0 with Samuel. + + * `TLS_INIT_TP_EXPENSIVE` is unused; Hurd def. can be removed. + + +# Documentation + +[[!taglink open_issue_documentation]] + + * IRC, freenode, #hurd, 2011-11-26 + + In glibc multiarch support (strcasecmp for i686 SSE3, etc.) + there is access to memory via gs: -- this will need to be changed for + us, right? + depends on the access + * `optimized strcasecmp and strncasecmp for x86-32` + (multiarch), + 76e3966e9efc3808a9e7ad09121c5dfc1211c20b + + 6abf346582ba678f4850a88b4a5950593841df1d + + 5583a0862cf94f71cbcde91c4043a20af65facca. `gs` + access. + + movl __libc_tsd_LOCALE@GOTNTPOFF(%ebx), %eax + that's handled by the linker fine + it's only the things held in the tcb_t structure which can pose + problem + tcbhead_t? + I'm looking at this. + So, at gs:0, there is the TCB. + And we have the same layout as NPTL/Linux, just that we + don't have as much data there as they have. + We're missing multiple_threads, sysinfo, sttack_guard, + pointer_guard, gscope_flag, private_futex, __private_tm[5]. + So, if one of these is referenced (be it my name or by + numeric offset), this is invalid for us. + Anything else should work equivalently. + yes + usually the only numeric offset being used is 0 + so it would simply not build + And the other offsers are generated via tcb-offsets.sym. + glibc's elf/stackguard-macros.h is wrong for us (but not + used anywhere apart from elf/tst-stackguard1.c, I think). + __thread __locale_t __libc_tsd_LOCALE = &_nl_global_locale; + -- this means that a __libc_tsd_LOCALE values will be in the TLS + segment, and this is what is being accessed from the assembler code + with %gs:__libc_tsd_LOCALE@NTPOFF, and the linker will resolve this. + yes + see in the nm output, the libc_tsd symbols + these provide the offsets + youpi: Thank you, I'm now understanding this part of TLS + much better. + have you had a look at the tls.pdf from Uli ? + all the gory details are there :) -- cgit v1.2.3