NetBSD-5.0.2/sys/arch/i386/i386/db_trace.c
/* $NetBSD: db_trace.c,v 1.60 2008/07/02 19:49:58 rmind Exp $ */
/*
* Mach Operating System
* Copyright (c) 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 the
* rights to redistribute these changes.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: db_trace.c,v 1.60 2008/07/02 19:49:58 rmind Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/user.h>
#include <machine/db_machdep.h>
#include <machine/frame.h>
#include <machine/trap.h>
#include <ddb/db_sym.h>
#include <ddb/db_access.h>
#include <ddb/db_variables.h>
#include <ddb/db_output.h>
#include <ddb/db_interface.h>
/*
* Machine set.
*/
#define dbreg(xx) (long *)offsetof(db_regs_t, tf_ ## xx)
static int db_i386_regop(const struct db_variable *, db_expr_t *, int);
const struct db_variable db_regs[] = {
{ "ds", dbreg(ds), db_i386_regop, NULL },
{ "es", dbreg(es), db_i386_regop, NULL },
{ "fs", dbreg(fs), db_i386_regop, NULL },
{ "gs", dbreg(gs), db_i386_regop, NULL },
{ "edi", dbreg(edi), db_i386_regop, NULL },
{ "esi", dbreg(esi), db_i386_regop, NULL },
{ "ebp", dbreg(ebp), db_i386_regop, NULL },
{ "ebx", dbreg(ebx), db_i386_regop, NULL },
{ "edx", dbreg(edx), db_i386_regop, NULL },
{ "ecx", dbreg(ecx), db_i386_regop, NULL },
{ "eax", dbreg(eax), db_i386_regop, NULL },
{ "eip", dbreg(eip), db_i386_regop, NULL },
{ "cs", dbreg(cs), db_i386_regop, NULL },
{ "eflags", dbreg(eflags), db_i386_regop, NULL },
{ "esp", dbreg(esp), db_i386_regop, NULL },
{ "ss", dbreg(ss), db_i386_regop, NULL },
};
const struct db_variable * const db_eregs =
db_regs + sizeof(db_regs)/sizeof(db_regs[0]);
static int
db_i386_regop (const struct db_variable *vp, db_expr_t *val, int opcode)
{
db_expr_t *regaddr =
(db_expr_t *)(((uint8_t *)DDB_REGS) + ((size_t)vp->valuep));
switch (opcode) {
case DB_VAR_GET:
*val = *regaddr;
break;
case DB_VAR_SET:
*regaddr = *val;
break;
default:
panic("db_i386_regop: unknown op %d", opcode);
}
return 0;
}
/*
* Stack trace.
*/
#define INKERNEL(va) (((vaddr_t)(va)) >= VM_MIN_KERNEL_ADDRESS)
struct i386_frame {
struct i386_frame *f_frame;
int f_retaddr;
int f_arg0;
};
#define NONE 0
#define TRAP 1
#define SYSCALL 2
#define INTERRUPT 3
#define INTERRUPT_TSS 4
#define TRAP_TSS 5
#define MAXNARG 16
db_addr_t db_trap_symbol_value = 0;
db_addr_t db_syscall_symbol_value = 0;
db_addr_t db_kdintr_symbol_value = 0;
bool db_trace_symbols_found = false;
#if 0
static void
db_find_trace_symbols(void)
{
db_expr_t value;
if (db_value_of_name("_trap", &value))
db_trap_symbol_value = (db_addr_t) value;
if (db_value_of_name("_kdintr", &value))
db_kdintr_symbol_value = (db_addr_t) value;
if (db_value_of_name("_syscall", &value))
db_syscall_symbol_value = (db_addr_t) value;
db_trace_symbols_found = true;
}
#endif
/*
* Figure out how many arguments were passed into the frame at "fp".
*/
static int
db_numargs(int *retaddrp)
{
int *argp;
int inst;
int args;
extern char etext[];
argp = (int *)db_get_value((int)retaddrp, 4, false);
if (argp < (int *)VM_MIN_KERNEL_ADDRESS || argp > (int *)etext) {
args = 10;
} else {
inst = db_get_value((int)argp, 4, false);
if ((inst & 0xff) == 0x59) /* popl %ecx */
args = 1;
else if ((inst & 0xffff) == 0xc483) /* addl %n, %esp */
args = ((inst >> 16) & 0xff) / 4;
else
args = 10;
}
return (args);
}
static db_sym_t
db_frame_info(int *frame, db_addr_t callpc, const char **namep, db_expr_t *offp,
int *is_trap, int *nargp)
{
db_expr_t offset;
db_sym_t sym;
int narg;
const char *name;
sym = db_search_symbol(callpc, DB_STGY_ANY, &offset);
db_symbol_values(sym, &name, NULL);
if (sym == (db_sym_t)0)
return (db_sym_t)0;
*is_trap = NONE;
narg = MAXNARG;
if (INKERNEL((int)frame) && name) {
/*
* XXX traps should be based off of the Xtrap*
* locations rather than on trap, since some traps
* (e.g., npxdna) don't go through trap()
*/
#ifdef __ELF__
if (!strcmp(name, "trap_tss")) {
*is_trap = TRAP_TSS;
narg = 0;
} else if (!strcmp(name, "trap")) {
*is_trap = TRAP;
narg = 0;
} else if (!strcmp(name, "syscall_plain") ||
!strcmp(name, "syscall_fancy")) {
*is_trap = SYSCALL;
narg = 0;
} else if (name[0] == 'X') {
if (!strncmp(name, "Xintr", 5) ||
!strncmp(name, "Xresume", 7) ||
!strncmp(name, "Xstray", 6) ||
!strncmp(name, "Xhold", 5) ||
!strncmp(name, "Xrecurse", 8) ||
!strcmp(name, "Xdoreti") ||
!strncmp(name, "Xsoft", 5)) {
*is_trap = INTERRUPT;
narg = 0;
} else if (!strncmp(name, "Xtss_", 5)) {
*is_trap = INTERRUPT_TSS;
narg = 0;
}
}
#else
if (!strcmp(name, "_trap_tss")) {
*is_trap = TRAP_TSS;
narg = 0;
} else if (!strcmp(name, "_trap")) {
*is_trap = TRAP;
narg = 0;
} else if (!strcmp(name, "_syscall")) {
*is_trap = SYSCALL;
narg = 0;
} else if (name[0] == '_' && name[1] == 'X') {
if (!strncmp(name, "_Xintr", 6) ||
!strncmp(name, "_Xresume", 8) ||
!strncmp(name, "_Xstray", 7) ||
!strncmp(name, "_Xhold", 6) ||
!strncmp(name, "_Xrecurse", 9) ||
!strcmp(name, "_Xdoreti") ||
!strncmp(name, "_Xsoft", 6)) {
*is_trap = INTERRUPT;
narg = 0;
} else if (!strncmp(name, "_Xtss_", 6)) {
*is_trap = INTERRUPT_TSS;
narg = 0;
}
}
#endif /* __ELF__ */
}
if (offp != NULL)
*offp = offset;
if (nargp != NULL)
*nargp = narg;
if (namep != NULL)
*namep = name;
return sym;
}
/*
* 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.
*/
static int
db_nextframe(
int **nextframe, /* IN/OUT */
int **retaddr, /* IN/OUT */
int **arg0, /* OUT */
db_addr_t *ip, /* OUT */
int *argp, /* IN */
int is_trap, void (*pr)(const char *, ...))
{
struct trapframe *tf;
struct i386tss *tss;
struct i386_frame *fp;
struct intrframe *ifp;
int traptype, trapno, err, i;
switch (is_trap) {
case NONE:
*ip = (db_addr_t)
db_get_value((int)*retaddr, 4, false);
fp = (struct i386_frame *)
db_get_value((int)*nextframe, 4, false);
if (fp == NULL)
return 0;
*nextframe = (int *)&fp->f_frame;
*retaddr = (int *)&fp->f_retaddr;
*arg0 = (int *)&fp->f_arg0;
break;
case TRAP_TSS:
case INTERRUPT_TSS:
tss = (struct i386tss *)*argp;
*ip = tss->__tss_eip;
fp = (struct i386_frame *)tss->tss_ebp;
if (fp == NULL)
return 0;
*nextframe = (int *)&fp->f_frame;
*retaddr = (int *)&fp->f_retaddr;
*arg0 = (int *)&fp->f_arg0;
if (is_trap == INTERRUPT_TSS)
(*pr)("--- interrupt via task gate ---\n");
else
(*pr)("--- trap via task gate ---\n");
break;
case TRAP:
case SYSCALL:
case INTERRUPT:
default:
/* The only argument to trap() or syscall() is the trapframe. */
tf = *(struct trapframe **)argp;
switch (is_trap) {
case TRAP:
(*pr)("--- trap (number %d) ---\n", tf->tf_trapno);
break;
case SYSCALL:
(*pr)("--- syscall (number %d) ---\n", tf->tf_eax);
break;
case INTERRUPT:
(*pr)("--- interrupt ---\n");
/*
* Get intrframe address as saved when switching
* to interrupt stack, and convert to trapframe
* (add 4). See frame.h.
*/
tf = (struct trapframe *)(*(argp - 1) + 4);
break;
}
*ip = (db_addr_t)tf->tf_eip;
fp = (struct i386_frame *)tf->tf_ebp;
if (fp == NULL)
return 0;
*nextframe = (int *)&fp->f_frame;
*retaddr = (int *)&fp->f_retaddr;
*arg0 = (int *)&fp->f_arg0;
break;
}
/*
* A bit of a hack. Since %ebp may be used in the stub code,
* walk the stack looking for a valid interrupt frame. Such
* a frame can be recognized by always having
* err 0 or IREENT_MAGIC and trapno T_ASTFLT.
*/
if (db_frame_info(*nextframe, (db_addr_t)*ip, NULL, NULL, &traptype,
NULL) != (db_sym_t)0
&& traptype == INTERRUPT) {
for (i = 0; i < 4; i++) {
ifp = (struct intrframe *)(argp + i);
err = db_get_value((int)&ifp->__if_err, 4, false);
trapno = db_get_value((int)&ifp->__if_trapno, 4, false);
if ((err == 0 || err == IREENT_MAGIC) && trapno == T_ASTFLT) {
*nextframe = (int *)ifp - 1;
break;
}
}
if (i == 4) {
(*pr)("DDB lost frame for ");
db_printsym(*ip, DB_STGY_ANY, pr);
(*pr)(", trying %p\n",argp);
*nextframe = argp;
}
}
return 1;
}
static bool
db_intrstack_p(const void *vp)
{
const struct cpu_info *ci;
CPU_INFO_ITERATOR cii;
for (CPU_INFO_FOREACH(cii, ci)) {
const char *cp = ci->ci_intrstack;
if (cp == NULL) {
continue;
}
if ((cp - INTRSTACKSIZE + 4) <= (const char *)vp &&
(const char *)vp <= cp) {
return true;
}
}
return false;
}
void
db_stack_trace_print(db_expr_t addr, bool have_addr, db_expr_t count,
const char *modif, void (*pr)(const char *, ...))
{
int *frame, *lastframe;
int *retaddr, *arg0;
int *argp;
db_addr_t callpc;
int is_trap = NONE;
bool kernel_only = true;
bool trace_thread = false;
bool lwpaddr = false;
#if 0
if (!db_trace_symbols_found)
db_find_trace_symbols();
#endif
{
const char *cp = modif;
char c;
while ((c = *cp++) != 0) {
if (c == 'a') {
lwpaddr = true;
trace_thread = true;
}
if (c == 't')
trace_thread = true;
if (c == 'u')
kernel_only = false;
}
}
if (!have_addr) {
frame = (int *)ddb_regs.tf_ebp;
callpc = (db_addr_t)ddb_regs.tf_eip;
} else {
if (trace_thread) {
struct proc *p;
struct user *u;
struct lwp *l;
if (lwpaddr) {
l = (struct lwp *)addr;
p = l->l_proc;
(*pr)("trace: pid %d ", p->p_pid);
} else {
(*pr)("trace: pid %d ", (int)addr);
p = p_find(addr, PFIND_LOCKED);
if (p == NULL) {
(*pr)("not found\n");
return;
}
l = LIST_FIRST(&p->p_lwps);
KASSERT(l != NULL);
}
(*pr)("lid %d ", l->l_lid);
if (!(l->l_flag & LW_INMEM)) {
(*pr)("swapped out\n");
return;
}
u = l->l_addr;
if (p == curproc && l == curlwp) {
frame = (int *)ddb_regs.tf_ebp;
callpc = (db_addr_t)ddb_regs.tf_eip;
(*pr)("at %p\n", frame);
} else {
frame = (int *)u->u_pcb.pcb_ebp;
callpc = (db_addr_t)
db_get_value((int)(frame + 1), 4, false);
(*pr)("at %p\n", frame);
frame = (int *)*frame; /* XXXfvdl db_get_value? */
}
} else {
frame = (int *)addr;
callpc = (db_addr_t)
db_get_value((int)(frame + 1), 4, false);
frame = (int *)*frame; /* XXXfvdl db_get_value? */
}
}
retaddr = frame + 1;
arg0 = frame + 2;
lastframe = 0;
while (count && frame != 0) {
int narg;
const char * name;
db_expr_t offset;
db_sym_t sym;
char *argnames[MAXNARG], **argnp = NULL;
db_addr_t lastcallpc;
name = "?";
is_trap = NONE;
offset = 0;
sym = db_frame_info(frame, callpc, &name, &offset, &is_trap,
&narg);
if (lastframe == 0 && sym == (db_sym_t)0) {
/* Symbol not found, peek at code */
int instr = db_get_value(callpc, 4, false);
offset = 1;
if ((instr & 0x00ffffff) == 0x00e58955 ||
/* enter: pushl %ebp, movl %esp, %ebp */
(instr & 0x0000ffff) == 0x0000e589
/* enter+1: movl %esp, %ebp */) {
offset = 0;
}
}
if (is_trap == NONE) {
if (db_sym_numargs(sym, &narg, argnames))
argnp = argnames;
else
narg = db_numargs(frame);
}
(*pr)("%s(", name);
if (lastframe == 0 && offset == 0 && !have_addr) {
/*
* We have a breakpoint before the frame is set up
* Use %esp instead
*/
argp = &((struct i386_frame *)(ddb_regs.tf_esp-4))->f_arg0;
} else {
argp = frame + 2;
}
while (narg) {
if (argnp)
(*pr)("%s=", *argnp++);
(*pr)("%lx", db_get_value((int)argp, 4, false));
argp++;
if (--narg != 0)
(*pr)(",");
}
(*pr)(") at ");
db_printsym(callpc, DB_STGY_PROC, pr);
(*pr)("\n");
if (lastframe == 0 && offset == 0 && !have_addr) {
/* Frame really belongs to next callpc */
struct i386_frame *fp = (void *)(ddb_regs.tf_esp-4);
lastframe = (int *)fp;
callpc = (db_addr_t)
db_get_value((db_addr_t)&fp->f_retaddr, 4, false);
continue;
}
lastframe = frame;
lastcallpc = callpc;
if (!db_nextframe(&frame, &retaddr, &arg0,
&callpc, frame + 2, is_trap, pr))
break;
if (INKERNEL((int)frame)) {
/* staying in kernel */
if (!db_intrstack_p(frame) &&
db_intrstack_p(lastframe)) {
(*pr)("--- switch to interrupt stack ---\n");
} else if (frame < lastframe ||
(frame == lastframe && callpc == lastcallpc)) {
(*pr)("Bad frame pointer: %p\n", frame);
break;
}
} else if (INKERNEL((int)lastframe)) {
/* switch from user to kernel */
if (kernel_only)
break; /* kernel stack only */
} else {
/* in user */
if (frame <= lastframe) {
(*pr)("Bad user frame pointer: %p\n",
frame);
break;
}
}
--count;
}
if (count && is_trap != NONE) {
db_printsym(callpc, DB_STGY_XTRN, pr);
(*pr)(":\n");
}
}