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|
/*
* Mach Operating System
* Copyright (c) 1993,1992,1991,1990 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
#if MACH_KDB
#include <string.h>
#include <mach/boolean.h>
#include <vm/vm_map.h>
#include <kern/thread.h>
#include <kern/task.h>
#include <machine/db_machdep.h>
#include <machine/machspl.h>
#include <ddb/db_access.h>
#include <ddb/db_command.h>
#include <ddb/db_output.h>
#include <ddb/db_sym.h>
#include <ddb/db_variables.h>
#include <ddb/db_task_thread.h>
#include "trap.h"
long
db_i386_reg_value(
struct db_variable *vp,
db_expr_t *valuep,
int flag,
struct db_var_aux_param *ap); /* forward */
/*
* Machine register set.
*/
struct db_variable db_regs[] = {
{ "cs", (long *)&ddb_regs.cs, db_i386_reg_value },
{ "ds", (long *)&ddb_regs.ds, db_i386_reg_value },
{ "es", (long *)&ddb_regs.es, db_i386_reg_value },
{ "fs", (long *)&ddb_regs.fs, db_i386_reg_value },
{ "gs", (long *)&ddb_regs.gs, db_i386_reg_value },
{ "ss", (long *)&ddb_regs.ss, db_i386_reg_value },
{ "eax",(long *)&ddb_regs.eax, db_i386_reg_value },
{ "ecx",(long *)&ddb_regs.ecx, db_i386_reg_value },
{ "edx",(long *)&ddb_regs.edx, db_i386_reg_value },
{ "ebx",(long *)&ddb_regs.ebx, db_i386_reg_value },
{ "esp",(long *)&ddb_regs.uesp,db_i386_reg_value },
{ "ebp",(long *)&ddb_regs.ebp, db_i386_reg_value },
{ "esi",(long *)&ddb_regs.esi, db_i386_reg_value },
{ "edi",(long *)&ddb_regs.edi, db_i386_reg_value },
{ "eip",(long *)&ddb_regs.eip, db_i386_reg_value },
{ "efl",(long *)&ddb_regs.efl, db_i386_reg_value },
};
struct db_variable *db_eregs = db_regs + sizeof(db_regs)/sizeof(db_regs[0]);
/*
* Stack trace.
*/
#define INKERNEL(va) (((vm_offset_t)(va)) >= VM_MIN_KERNEL_ADDRESS)
struct i386_frame {
struct i386_frame *f_frame;
long f_retaddr;
long f_arg0;
};
#define TRAP 1
#define INTERRUPT 2
#define SYSCALL 3
db_addr_t db_user_trap_symbol_value = 0;
db_addr_t db_kernel_trap_symbol_value = 0;
db_addr_t db_interrupt_symbol_value = 0;
db_addr_t db_return_to_iret_symbol_value = 0;
db_addr_t db_syscall_symbol_value = 0;
boolean_t db_trace_symbols_found = FALSE;
struct i386_kregs {
char *name;
long offset;
} i386_kregs[] = {
{ "ebx", (long)(&((struct i386_kernel_state *)0)->k_ebx) },
{ "esp", (long)(&((struct i386_kernel_state *)0)->k_esp) },
{ "ebp", (long)(&((struct i386_kernel_state *)0)->k_ebp) },
{ "edi", (long)(&((struct i386_kernel_state *)0)->k_edi) },
{ "esi", (long)(&((struct i386_kernel_state *)0)->k_esi) },
{ "eip", (long)(&((struct i386_kernel_state *)0)->k_eip) },
{ 0 },
};
long *
db_lookup_i386_kreg(
char *name,
int *kregp)
{
struct i386_kregs *kp;
for (kp = i386_kregs; kp->name; kp++) {
if (strcmp(name, kp->name) == 0)
return (long *)((long)kregp + kp->offset);
}
return 0;
}
long
db_i386_reg_value(
struct db_variable *vp,
db_expr_t *valuep,
int flag,
db_var_aux_param_t ap)
{
long *dp = 0;
db_expr_t null_reg = 0;
thread_t thread = ap->thread;
extern unsigned int_stack_high;
if (db_option(ap->modif, 'u')) {
if (thread == THREAD_NULL) {
if ((thread = current_thread()) == THREAD_NULL)
db_error("no user registers\n");
}
if (thread == current_thread()) {
if (ddb_regs.cs & 0x3)
dp = vp->valuep;
else if (ddb_regs.ebp < int_stack_high)
db_error("cannot get/set user registers in nested interrupt\n");
}
} else {
if (thread == THREAD_NULL || thread == current_thread()) {
dp = vp->valuep;
} else if ((thread->state & TH_SWAPPED) == 0 &&
thread->kernel_stack) {
dp = db_lookup_i386_kreg(vp->name,
(long *)(STACK_IKS(thread->kernel_stack)));
if (dp == 0)
dp = &null_reg;
} else if ((thread->state & TH_SWAPPED) &&
thread->swap_func != thread_exception_return) {
/*.....this breaks t/t $taskN.0...*/
/* only EIP is valid */
if (vp->valuep == (long *) &ddb_regs.eip) {
dp = (long *)(&thread->swap_func);
} else {
dp = &null_reg;
}
}
}
if (dp == 0) {
if (thread->pcb == 0)
db_error("no pcb\n");
dp = (long *)((long)(&thread->pcb->iss) +
((long)vp->valuep - (long)&ddb_regs));
}
if (flag == DB_VAR_SET)
*dp = *valuep;
else
*valuep = *dp;
}
void
db_find_trace_symbols(void)
{
db_expr_t value;
#ifdef __ELF__
#define P
#else
#define P "_"
#endif
if (db_value_of_name(P"user_trap", &value))
db_user_trap_symbol_value = (db_addr_t) value;
if (db_value_of_name(P"kernel_trap", &value))
db_kernel_trap_symbol_value = (db_addr_t) value;
if (db_value_of_name(P"interrupt", &value))
db_interrupt_symbol_value = (db_addr_t) value;
if (db_value_of_name(P"return_to_iret", &value))
db_return_to_iret_symbol_value = (db_addr_t) value;
if (db_value_of_name(P"syscall", &value))
db_syscall_symbol_value = (db_addr_t) value;
#undef P
db_trace_symbols_found = TRUE;
}
/*
* Figure out how many arguments were passed into the frame at "fp".
*/
int db_numargs_default = 5;
int
db_numargs(
struct i386_frame *fp,
task_t task)
{
long *argp;
long inst;
long args;
extern char etext[];
argp = (long *)db_get_task_value((long)&fp->f_retaddr, sizeof(long), FALSE, task);
if (argp < (long *)VM_MIN_KERNEL_ADDRESS || argp > (long *)etext)
args = db_numargs_default;
else if (!DB_CHECK_ACCESS((long)argp, sizeof(long), task))
args = db_numargs_default;
else {
inst = db_get_task_value((long)argp, sizeof(long), FALSE, task);
if ((inst & 0xff) == 0x59) /* popl %ecx */
args = 1;
else if ((inst & 0xffff) == 0xc483) /* addl %n, %esp */
args = ((inst >> 16) & 0xff) / 4;
else
args = db_numargs_default;
}
return args;
}
struct interrupt_frame {
struct i386_frame *if_frame; /* point to next frame */
long if_retaddr; /* return address to _interrupt */
long if_unit; /* unit number */
spl_t if_spl; /* saved spl */
long if_iretaddr; /* _return_to_{iret,iret_i} */
long if_edx; /* old sp(iret) or saved edx(iret_i) */
long if_ecx; /* saved ecx(iret_i) */
long if_eax; /* saved eax(iret_i) */
long if_eip; /* saved eip(iret_i) */
long if_cs; /* saved cs(iret_i) */
long if_efl; /* saved efl(iret_i) */
};
/*
* Figure out the next frame up in the call stack.
* For trap(), we print the address of the faulting instruction and
* proceed with the calling frame. We return the ip that faulted.
* If the trap was caused by jumping through a bogus pointer, then
* the next line in the backtrace will list some random function as
* being called. It should get the argument list correct, though.
* It might be possible to dig out from the next frame up the name
* of the function that faulted, but that could get hairy.
*/
void
db_nextframe(
struct i386_frame **lfp, /* in/out */
struct i386_frame **fp, /* in/out */
db_addr_t *ip, /* out */
long frame_type, /* in */
thread_t thread) /* in */
{
struct i386_saved_state *saved_regs;
struct interrupt_frame *ifp;
task_t task = (thread != THREAD_NULL)? thread->task: TASK_NULL;
switch(frame_type) {
case TRAP:
/*
* We know that trap() has 1 argument and we know that
* it is an (struct i386_saved_state *).
*/
saved_regs = (struct i386_saved_state *)
db_get_task_value((long)&((*fp)->f_arg0),sizeof(long),FALSE,task);
db_printf(">>>>> %s (%d) at ",
trap_name(saved_regs->trapno), saved_regs->trapno);
db_task_printsym(saved_regs->eip, DB_STGY_PROC, task);
db_printf(" <<<<<\n");
*fp = (struct i386_frame *)saved_regs->ebp;
*ip = (db_addr_t)saved_regs->eip;
break;
case INTERRUPT:
if (*lfp == 0) {
db_printf(">>>>> interrupt <<<<<\n");
goto miss_frame;
}
db_printf(">>>>> interrupt at ");
ifp = (struct interrupt_frame *)(*lfp);
*fp = ifp->if_frame;
if (ifp->if_iretaddr == db_return_to_iret_symbol_value)
*ip = ((struct i386_interrupt_state *) ifp->if_edx)->eip;
else
*ip = (db_addr_t) ifp->if_eip;
db_task_printsym(*ip, DB_STGY_PROC, task);
db_printf(" <<<<<\n");
break;
case SYSCALL:
if (thread != THREAD_NULL && thread->pcb) {
*ip = (db_addr_t) thread->pcb->iss.eip;
*fp = (struct i386_frame *) thread->pcb->iss.ebp;
break;
}
/* falling down for unknown case */
default:
miss_frame:
*ip = (db_addr_t)
db_get_task_value((long)&(*fp)->f_retaddr, sizeof(long), FALSE, task);
*lfp = *fp;
*fp = (struct i386_frame *)
db_get_task_value((long)&(*fp)->f_frame, sizeof(long), FALSE, task);
break;
}
}
void
db_i386_stack_trace(
thread_t th,
struct i386_frame *frame,
db_addr_t callpc,
db_expr_t count,
int flags); /* forward */
#define F_USER_TRACE 1
#define F_TRACE_THREAD 2
void
db_stack_trace_cmd(
db_expr_t addr,
boolean_t have_addr,
db_expr_t count,
char *modif)
{
boolean_t trace_thread = FALSE;
struct i386_frame *frame;
db_addr_t callpc;
int flags = 0;
thread_t th;
{
char *cp = modif;
char c;
while ((c = *cp++) != 0) {
if (c == 't')
trace_thread = TRUE;
if (c == 'u')
flags |= F_USER_TRACE;
}
}
if (!have_addr && !trace_thread) {
frame = (struct i386_frame *)ddb_regs.ebp;
callpc = (db_addr_t)ddb_regs.eip;
th = current_thread();
} else if (trace_thread) {
if (have_addr) {
th = (thread_t) addr;
if (!db_check_thread_address_valid((db_addr_t)th))
return;
} else {
th = db_default_thread;
if (th == THREAD_NULL)
th = current_thread();
if (th == THREAD_NULL) {
db_printf("no active thread\n");
return;
}
}
if (th == current_thread()) {
frame = (struct i386_frame *)ddb_regs.ebp;
callpc = (db_addr_t)ddb_regs.eip;
} else {
if (th->pcb == 0) {
db_printf("thread has no pcb\n");
return;
}
if ((th->state & TH_SWAPPED) || th->kernel_stack == 0) {
struct i386_saved_state *iss = &th->pcb->iss;
db_printf("Continuation ");
db_task_printsym((db_expr_t)th->swap_func,
DB_STGY_PROC,
th->task);
db_printf("\n");
frame = (struct i386_frame *) (iss->ebp);
callpc = (db_addr_t) (iss->eip);
} else {
struct i386_kernel_state *iks;
iks = STACK_IKS(th->kernel_stack);
frame = (struct i386_frame *) (iks->k_ebp);
callpc = (db_addr_t) (iks->k_eip);
}
}
} else {
frame = (struct i386_frame *)addr;
th = (db_default_thread)? db_default_thread: current_thread();
callpc = (db_addr_t)db_get_task_value((long)&frame->f_retaddr, sizeof(long),
FALSE,
(th == THREAD_NULL) ? TASK_NULL : th->task);
}
db_i386_stack_trace( th, frame, callpc, count, flags );
}
void
db_i386_stack_trace(
thread_t th,
struct i386_frame *frame,
db_addr_t callpc,
db_expr_t count,
int flags)
{
task_t task;
boolean_t kernel_only;
long *argp;
long user_frame = 0;
struct i386_frame *lastframe;
int frame_type;
char *filename;
int linenum;
extern unsigned long db_maxoff;
if (count == -1)
count = 65535;
kernel_only = (flags & F_USER_TRACE) == 0;
task = (th == THREAD_NULL) ? TASK_NULL : th->task;
if (!db_trace_symbols_found)
db_find_trace_symbols();
if (!INKERNEL((unsigned long)callpc) && !INKERNEL((unsigned long)frame)) {
db_printf(">>>>> user space <<<<<\n");
user_frame++;
}
lastframe = 0;
while (count-- && frame != 0) {
int narg;
char * name;
db_expr_t offset;
if (INKERNEL((unsigned long)callpc) && user_frame == 0) {
db_addr_t call_func = 0;
db_sym_t sym_tmp;
db_symbol_values(0,
sym_tmp = db_search_task_symbol(callpc,
DB_STGY_XTRN,
(db_addr_t *)&offset,
TASK_NULL),
&name, (db_expr_t *)&call_func);
db_free_symbol(sym_tmp);
if ((db_user_trap_symbol_value && call_func == db_user_trap_symbol_value) ||
(db_kernel_trap_symbol_value && call_func == db_kernel_trap_symbol_value)) {
frame_type = TRAP;
narg = 1;
} else if (db_interrupt_symbol_value && call_func == db_interrupt_symbol_value) {
frame_type = INTERRUPT;
goto next_frame;
} else if (db_syscall_symbol_value && call_func == db_syscall_symbol_value) {
frame_type = SYSCALL;
goto next_frame;
} else {
frame_type = 0;
narg = db_numargs(frame, task);
}
} else if (INKERNEL((unsigned long)callpc) ^ INKERNEL((unsigned long)frame)) {
frame_type = 0;
narg = -1;
} else {
frame_type = 0;
narg = db_numargs(frame, task);
}
db_find_task_sym_and_offset(callpc, &name,
(db_addr_t *)&offset, task);
if (name == 0 || offset > db_maxoff) {
db_printf("0x%x(", callpc);
offset = 0;
} else
db_printf("%s(", name);
argp = &frame->f_arg0;
while (narg > 0) {
db_printf("%x", db_get_task_value((long)argp,sizeof(long),FALSE,task));
argp++;
if (--narg != 0)
db_printf(",");
}
if (narg < 0)
db_printf("...");
db_printf(")");
if (offset) {
db_printf("+%x", offset);
}
if (db_line_at_pc(0, &filename, &linenum, callpc)) {
db_printf(" [%s", filename);
if (linenum > 0)
db_printf(":%d", linenum);
db_printf("]");
}
db_printf("\n");
next_frame:
db_nextframe(&lastframe, &frame, &callpc, frame_type, th);
if (frame == 0) {
/* end of chain */
break;
}
if (!INKERNEL(lastframe) ||
(!INKERNEL((unsigned long)callpc) && !INKERNEL((unsigned long)frame)))
user_frame++;
if (user_frame == 1) {
db_printf(">>>>> user space <<<<<\n");
if (kernel_only)
break;
}
if (frame <= lastframe) {
if (INKERNEL(lastframe) && !INKERNEL(frame))
continue;
db_printf("Bad frame pointer: 0x%x\n", frame);
break;
}
}
}
#define CTHREADS_SUPPORT 1
#if CTHREADS_SUPPORT
thread_t
db_find_kthread(
vm_offset_t ustack_base,
vm_size_t ustack_top,
task_t task)
{
thread_t thread;
queue_iterate(&task->thread_list, thread, thread_t, thread_list) {
vm_offset_t usp = thread->pcb->iss.uesp/*ebp works*/;
if (usp >= ustack_base && usp < ustack_top)
return thread;
}
return THREAD_NULL;
}
static void db_cproc_state(
int state,
char s[4])
{
if (state == 0) {
*s++ = 'R';
} else {
if (state & 1) *s++ = 'S';
if (state & 2) *s++ = 'B';
if (state & 4) *s++ = 'C';
}
*s = 0;
}
/* offsets in a cproc structure */
/* TODO: longs? */
int db_cproc_next_offset = 0 * 4;
int db_cproc_incarnation_offset = 1 * 4;
int db_cproc_list_offset = 2 * 4;
int db_cproc_wait_offset = 3 * 4;
int db_cproc_context_offset = 5 * 4;
int db_cproc_state_offset = 7 * 4;
int db_cproc_stack_base_offset = 10 * 4 + sizeof(mach_msg_header_t);
int db_cproc_stack_size_offset = 11 * 4 + sizeof(mach_msg_header_t);
/* offsets in a cproc_switch context structure */
int db_cprocsw_framep_offset = 3 * 4;
int db_cprocsw_pc_offset = 4 * 4;
#include <machine/setjmp.h>
extern jmp_buf_t *db_recover;
void db_trace_cproc(
vm_offset_t cproc,
thread_t thread)
{
jmp_buf_t db_jmpbuf;
jmp_buf_t *prev = db_recover;
task_t task;
db_addr_t pc, fp;
task = (thread == THREAD_NULL)? TASK_NULL: thread->task;
if (!_setjmp(db_recover = &db_jmpbuf)) {
char pstate[4];
unsigned int s, w, n, c, cth;
s = db_get_task_value(cproc + db_cproc_state_offset, 4, FALSE, task);
w = db_get_task_value(cproc + db_cproc_wait_offset, 4, FALSE, task);
n = db_get_task_value(cproc + db_cproc_next_offset, 4, FALSE, task);
c = db_get_task_value(cproc + db_cproc_context_offset, 4, FALSE, task);
cth = db_get_task_value(cproc + db_cproc_incarnation_offset, 4, FALSE, task);
db_cproc_state(s, pstate);
db_printf("CThread %x (cproc %x) %s", cth, cproc, pstate);
if (w) db_printf(" awaits %x", w);
if (n) db_printf(" next %x", n);
db_printf("\n");
if ((s != 0) && (c != 0)) {
pc = db_get_task_value(c + db_cprocsw_pc_offset, 4, FALSE, task);
fp = c + db_cprocsw_framep_offset;
} else {
db_addr_t sb;
vm_size_t ss;
sb = db_get_task_value(cproc + db_cproc_stack_base_offset, sizeof(db_expr_t), FALSE, task);
ss = db_get_task_value(cproc + db_cproc_stack_size_offset, sizeof(db_expr_t), FALSE, task);
db_printf(" Stack base: %x\n", sb);
/*
* Lessee now..
*/
thread = db_find_kthread(sb, sb+ss, task);
if (thread != THREAD_NULL) {
pc = thread->pcb->iss.eip;
fp = thread->pcb->iss.ebp;
} else
fp = -1;
}
if (fp != -1)
db_i386_stack_trace(thread, (struct i386_frame*)fp, pc,
-1, F_USER_TRACE);
}
db_recover = prev;
}
void db_all_cprocs(
task_t task,
db_expr_t cproc_list)
{
jmp_buf_t db_jmpbuf;
jmp_buf_t *prev = db_recover;
thread_t thread;
db_expr_t cproc, next;
if (task != TASK_NULL) {
thread = (thread_t) queue_first(&task->thread_list);
} else
thread = current_thread();
if (cproc_list != 0)
next = cproc_list;
else
if (!db_value_of_name("unix::cproc_list", &next)) {
db_printf("No cprocs.\n");
return;
}
while (next) {
if (_setjmp(db_recover = &db_jmpbuf))
break;
cproc = db_get_task_value(next, 4, FALSE, TASK_NULL);
if (cproc == 0) break;
next = cproc + db_cproc_list_offset;
db_trace_cproc(cproc, thread);
}
db_recover = prev;
}
#endif /* CTHREADS_SUPPORT */
#endif /* MACH_KDB */
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