mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-16 10:20:30 +00:00
fcbb889fdb
Set curthread->td_stopsched when entering kdb via any vector. Previously, it was only set when entering via panic, so when entering kdb another way, mutexes and such were still "live", and an attempt to lock an already locked mutex would panic. Reviewed by: kib, cem Discussed with: jhb Tested by: pho MFC after: 2 months Sponsored by: Dell EMC Isilon Differential Revision: https://reviews.freebsd.org/D17687
717 lines
15 KiB
C
717 lines
15 KiB
C
/*-
|
|
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
|
|
*
|
|
* Copyright (c) 2004 The FreeBSD Project
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|
* IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
|
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include "opt_kdb.h"
|
|
#include "opt_stack.h"
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/cons.h>
|
|
#include <sys/kdb.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/pcpu.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/sbuf.h>
|
|
#include <sys/smp.h>
|
|
#include <sys/stack.h>
|
|
#include <sys/sysctl.h>
|
|
|
|
#include <machine/kdb.h>
|
|
#include <machine/pcb.h>
|
|
|
|
#ifdef SMP
|
|
#include <machine/smp.h>
|
|
#endif
|
|
|
|
u_char __read_frequently kdb_active = 0;
|
|
static void *kdb_jmpbufp = NULL;
|
|
struct kdb_dbbe *kdb_dbbe = NULL;
|
|
static struct pcb kdb_pcb;
|
|
struct pcb *kdb_thrctx = NULL;
|
|
struct thread *kdb_thread = NULL;
|
|
struct trapframe *kdb_frame = NULL;
|
|
|
|
#ifdef BREAK_TO_DEBUGGER
|
|
#define KDB_BREAK_TO_DEBUGGER 1
|
|
#else
|
|
#define KDB_BREAK_TO_DEBUGGER 0
|
|
#endif
|
|
|
|
#ifdef ALT_BREAK_TO_DEBUGGER
|
|
#define KDB_ALT_BREAK_TO_DEBUGGER 1
|
|
#else
|
|
#define KDB_ALT_BREAK_TO_DEBUGGER 0
|
|
#endif
|
|
|
|
static int kdb_break_to_debugger = KDB_BREAK_TO_DEBUGGER;
|
|
static int kdb_alt_break_to_debugger = KDB_ALT_BREAK_TO_DEBUGGER;
|
|
|
|
KDB_BACKEND(null, NULL, NULL, NULL, NULL);
|
|
SET_DECLARE(kdb_dbbe_set, struct kdb_dbbe);
|
|
|
|
static int kdb_sysctl_available(SYSCTL_HANDLER_ARGS);
|
|
static int kdb_sysctl_current(SYSCTL_HANDLER_ARGS);
|
|
static int kdb_sysctl_enter(SYSCTL_HANDLER_ARGS);
|
|
static int kdb_sysctl_panic(SYSCTL_HANDLER_ARGS);
|
|
static int kdb_sysctl_trap(SYSCTL_HANDLER_ARGS);
|
|
static int kdb_sysctl_trap_code(SYSCTL_HANDLER_ARGS);
|
|
static int kdb_sysctl_stack_overflow(SYSCTL_HANDLER_ARGS);
|
|
|
|
static SYSCTL_NODE(_debug, OID_AUTO, kdb, CTLFLAG_RW, NULL, "KDB nodes");
|
|
|
|
SYSCTL_PROC(_debug_kdb, OID_AUTO, available, CTLTYPE_STRING | CTLFLAG_RD, NULL,
|
|
0, kdb_sysctl_available, "A", "list of available KDB backends");
|
|
|
|
SYSCTL_PROC(_debug_kdb, OID_AUTO, current, CTLTYPE_STRING | CTLFLAG_RW, NULL,
|
|
0, kdb_sysctl_current, "A", "currently selected KDB backend");
|
|
|
|
SYSCTL_PROC(_debug_kdb, OID_AUTO, enter,
|
|
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, NULL, 0,
|
|
kdb_sysctl_enter, "I", "set to enter the debugger");
|
|
|
|
SYSCTL_PROC(_debug_kdb, OID_AUTO, panic,
|
|
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, NULL, 0,
|
|
kdb_sysctl_panic, "I", "set to panic the kernel");
|
|
|
|
SYSCTL_PROC(_debug_kdb, OID_AUTO, trap,
|
|
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, NULL, 0,
|
|
kdb_sysctl_trap, "I", "set to cause a page fault via data access");
|
|
|
|
SYSCTL_PROC(_debug_kdb, OID_AUTO, trap_code,
|
|
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, NULL, 0,
|
|
kdb_sysctl_trap_code, "I", "set to cause a page fault via code access");
|
|
|
|
SYSCTL_PROC(_debug_kdb, OID_AUTO, stack_overflow,
|
|
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, NULL, 0,
|
|
kdb_sysctl_stack_overflow, "I", "set to cause a stack overflow");
|
|
|
|
SYSCTL_INT(_debug_kdb, OID_AUTO, break_to_debugger,
|
|
CTLFLAG_RWTUN | CTLFLAG_SECURE,
|
|
&kdb_break_to_debugger, 0, "Enable break to debugger");
|
|
|
|
SYSCTL_INT(_debug_kdb, OID_AUTO, alt_break_to_debugger,
|
|
CTLFLAG_RWTUN | CTLFLAG_SECURE,
|
|
&kdb_alt_break_to_debugger, 0, "Enable alternative break to debugger");
|
|
|
|
/*
|
|
* Flag to indicate to debuggers why the debugger was entered.
|
|
*/
|
|
const char * volatile kdb_why = KDB_WHY_UNSET;
|
|
|
|
static int
|
|
kdb_sysctl_available(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
struct kdb_dbbe **iter;
|
|
struct sbuf sbuf;
|
|
int error;
|
|
|
|
sbuf_new_for_sysctl(&sbuf, NULL, 64, req);
|
|
SET_FOREACH(iter, kdb_dbbe_set) {
|
|
if ((*iter)->dbbe_active == 0)
|
|
sbuf_printf(&sbuf, "%s ", (*iter)->dbbe_name);
|
|
}
|
|
error = sbuf_finish(&sbuf);
|
|
sbuf_delete(&sbuf);
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
kdb_sysctl_current(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
char buf[16];
|
|
int error;
|
|
|
|
if (kdb_dbbe != NULL)
|
|
strlcpy(buf, kdb_dbbe->dbbe_name, sizeof(buf));
|
|
else
|
|
*buf = '\0';
|
|
error = sysctl_handle_string(oidp, buf, sizeof(buf), req);
|
|
if (error != 0 || req->newptr == NULL)
|
|
return (error);
|
|
if (kdb_active)
|
|
return (EBUSY);
|
|
return (kdb_dbbe_select(buf));
|
|
}
|
|
|
|
static int
|
|
kdb_sysctl_enter(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
int error, i;
|
|
|
|
error = sysctl_wire_old_buffer(req, sizeof(int));
|
|
if (error == 0) {
|
|
i = 0;
|
|
error = sysctl_handle_int(oidp, &i, 0, req);
|
|
}
|
|
if (error != 0 || req->newptr == NULL)
|
|
return (error);
|
|
if (kdb_active)
|
|
return (EBUSY);
|
|
kdb_enter(KDB_WHY_SYSCTL, "sysctl debug.kdb.enter");
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
kdb_sysctl_panic(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
int error, i;
|
|
|
|
error = sysctl_wire_old_buffer(req, sizeof(int));
|
|
if (error == 0) {
|
|
i = 0;
|
|
error = sysctl_handle_int(oidp, &i, 0, req);
|
|
}
|
|
if (error != 0 || req->newptr == NULL)
|
|
return (error);
|
|
panic("kdb_sysctl_panic");
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
kdb_sysctl_trap(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
int error, i;
|
|
int *addr = (int *)0x10;
|
|
|
|
error = sysctl_wire_old_buffer(req, sizeof(int));
|
|
if (error == 0) {
|
|
i = 0;
|
|
error = sysctl_handle_int(oidp, &i, 0, req);
|
|
}
|
|
if (error != 0 || req->newptr == NULL)
|
|
return (error);
|
|
return (*addr);
|
|
}
|
|
|
|
static int
|
|
kdb_sysctl_trap_code(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
int error, i;
|
|
void (*fp)(u_int, u_int, u_int) = (void *)0xdeadc0de;
|
|
|
|
error = sysctl_wire_old_buffer(req, sizeof(int));
|
|
if (error == 0) {
|
|
i = 0;
|
|
error = sysctl_handle_int(oidp, &i, 0, req);
|
|
}
|
|
if (error != 0 || req->newptr == NULL)
|
|
return (error);
|
|
(*fp)(0x11111111, 0x22222222, 0x33333333);
|
|
return (0);
|
|
}
|
|
|
|
static void kdb_stack_overflow(volatile int *x) __noinline;
|
|
static void
|
|
kdb_stack_overflow(volatile int *x)
|
|
{
|
|
|
|
if (*x > 10000000)
|
|
return;
|
|
kdb_stack_overflow(x);
|
|
*x += PCPU_GET(cpuid) / 1000000;
|
|
}
|
|
|
|
static int
|
|
kdb_sysctl_stack_overflow(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
int error, i;
|
|
volatile int x;
|
|
|
|
error = sysctl_wire_old_buffer(req, sizeof(int));
|
|
if (error == 0) {
|
|
i = 0;
|
|
error = sysctl_handle_int(oidp, &i, 0, req);
|
|
}
|
|
if (error != 0 || req->newptr == NULL)
|
|
return (error);
|
|
x = 0;
|
|
kdb_stack_overflow(&x);
|
|
return (0);
|
|
}
|
|
|
|
|
|
void
|
|
kdb_panic(const char *msg)
|
|
{
|
|
|
|
printf("KDB: panic\n");
|
|
panic("%s", msg);
|
|
}
|
|
|
|
void
|
|
kdb_reboot(void)
|
|
{
|
|
|
|
printf("KDB: reboot requested\n");
|
|
shutdown_nice(0);
|
|
}
|
|
|
|
/*
|
|
* Solaris implements a new BREAK which is initiated by a character sequence
|
|
* CR ~ ^b which is similar to a familiar pattern used on Sun servers by the
|
|
* Remote Console.
|
|
*
|
|
* Note that this function may be called from almost anywhere, with interrupts
|
|
* disabled and with unknown locks held, so it must not access data other than
|
|
* its arguments. Its up to the caller to ensure that the state variable is
|
|
* consistent.
|
|
*/
|
|
#define KEY_CR 13 /* CR '\r' */
|
|
#define KEY_TILDE 126 /* ~ */
|
|
#define KEY_CRTLB 2 /* ^B */
|
|
#define KEY_CRTLP 16 /* ^P */
|
|
#define KEY_CRTLR 18 /* ^R */
|
|
|
|
/* States of th KDB "alternate break sequence" detecting state machine. */
|
|
enum {
|
|
KDB_ALT_BREAK_SEEN_NONE,
|
|
KDB_ALT_BREAK_SEEN_CR,
|
|
KDB_ALT_BREAK_SEEN_CR_TILDE,
|
|
};
|
|
|
|
int
|
|
kdb_break(void)
|
|
{
|
|
|
|
if (!kdb_break_to_debugger)
|
|
return (0);
|
|
kdb_enter(KDB_WHY_BREAK, "Break to debugger");
|
|
return (KDB_REQ_DEBUGGER);
|
|
}
|
|
|
|
static int
|
|
kdb_alt_break_state(int key, int *state)
|
|
{
|
|
int brk;
|
|
|
|
/* All states transition to KDB_ALT_BREAK_SEEN_CR on a CR. */
|
|
if (key == KEY_CR) {
|
|
*state = KDB_ALT_BREAK_SEEN_CR;
|
|
return (0);
|
|
}
|
|
|
|
brk = 0;
|
|
switch (*state) {
|
|
case KDB_ALT_BREAK_SEEN_CR:
|
|
*state = KDB_ALT_BREAK_SEEN_NONE;
|
|
if (key == KEY_TILDE)
|
|
*state = KDB_ALT_BREAK_SEEN_CR_TILDE;
|
|
break;
|
|
case KDB_ALT_BREAK_SEEN_CR_TILDE:
|
|
*state = KDB_ALT_BREAK_SEEN_NONE;
|
|
if (key == KEY_CRTLB)
|
|
brk = KDB_REQ_DEBUGGER;
|
|
else if (key == KEY_CRTLP)
|
|
brk = KDB_REQ_PANIC;
|
|
else if (key == KEY_CRTLR)
|
|
brk = KDB_REQ_REBOOT;
|
|
break;
|
|
case KDB_ALT_BREAK_SEEN_NONE:
|
|
default:
|
|
*state = KDB_ALT_BREAK_SEEN_NONE;
|
|
break;
|
|
}
|
|
return (brk);
|
|
}
|
|
|
|
static int
|
|
kdb_alt_break_internal(int key, int *state, int force_gdb)
|
|
{
|
|
int brk;
|
|
|
|
if (!kdb_alt_break_to_debugger)
|
|
return (0);
|
|
brk = kdb_alt_break_state(key, state);
|
|
switch (brk) {
|
|
case KDB_REQ_DEBUGGER:
|
|
if (force_gdb)
|
|
kdb_dbbe_select("gdb");
|
|
kdb_enter(KDB_WHY_BREAK, "Break to debugger");
|
|
break;
|
|
|
|
case KDB_REQ_PANIC:
|
|
if (force_gdb)
|
|
kdb_dbbe_select("gdb");
|
|
kdb_panic("Panic sequence on console");
|
|
break;
|
|
|
|
case KDB_REQ_REBOOT:
|
|
kdb_reboot();
|
|
break;
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
kdb_alt_break(int key, int *state)
|
|
{
|
|
|
|
return (kdb_alt_break_internal(key, state, 0));
|
|
}
|
|
|
|
/*
|
|
* This variation on kdb_alt_break() is used only by dcons, which has its own
|
|
* configuration flag to force GDB use regardless of the global KDB
|
|
* configuration.
|
|
*/
|
|
int
|
|
kdb_alt_break_gdb(int key, int *state)
|
|
{
|
|
|
|
return (kdb_alt_break_internal(key, state, 1));
|
|
}
|
|
|
|
/*
|
|
* Print a backtrace of the calling thread. The backtrace is generated by
|
|
* the selected debugger, provided it supports backtraces. If no debugger
|
|
* is selected or the current debugger does not support backtraces, this
|
|
* function silently returns.
|
|
*/
|
|
void
|
|
kdb_backtrace(void)
|
|
{
|
|
|
|
if (kdb_dbbe != NULL && kdb_dbbe->dbbe_trace != NULL) {
|
|
printf("KDB: stack backtrace:\n");
|
|
kdb_dbbe->dbbe_trace();
|
|
}
|
|
#ifdef STACK
|
|
else {
|
|
struct stack st;
|
|
|
|
printf("KDB: stack backtrace:\n");
|
|
stack_zero(&st);
|
|
stack_save(&st);
|
|
stack_print_ddb(&st);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Similar to kdb_backtrace() except that it prints a backtrace of an
|
|
* arbitrary thread rather than the calling thread.
|
|
*/
|
|
void
|
|
kdb_backtrace_thread(struct thread *td)
|
|
{
|
|
|
|
if (kdb_dbbe != NULL && kdb_dbbe->dbbe_trace_thread != NULL) {
|
|
printf("KDB: stack backtrace of thread %d:\n", td->td_tid);
|
|
kdb_dbbe->dbbe_trace_thread(td);
|
|
}
|
|
#ifdef STACK
|
|
else {
|
|
struct stack st;
|
|
|
|
printf("KDB: stack backtrace of thread %d:\n", td->td_tid);
|
|
stack_zero(&st);
|
|
stack_save_td(&st, td);
|
|
stack_print_ddb(&st);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Set/change the current backend.
|
|
*/
|
|
int
|
|
kdb_dbbe_select(const char *name)
|
|
{
|
|
struct kdb_dbbe *be, **iter;
|
|
|
|
SET_FOREACH(iter, kdb_dbbe_set) {
|
|
be = *iter;
|
|
if (be->dbbe_active == 0 && strcmp(be->dbbe_name, name) == 0) {
|
|
kdb_dbbe = be;
|
|
return (0);
|
|
}
|
|
}
|
|
return (EINVAL);
|
|
}
|
|
|
|
/*
|
|
* Enter the currently selected debugger. If a message has been provided,
|
|
* it is printed first. If the debugger does not support the enter method,
|
|
* it is entered by using breakpoint(), which enters the debugger through
|
|
* kdb_trap(). The 'why' argument will contain a more mechanically usable
|
|
* string than 'msg', and is relied upon by DDB scripting to identify the
|
|
* reason for entering the debugger so that the right script can be run.
|
|
*/
|
|
void
|
|
kdb_enter(const char *why, const char *msg)
|
|
{
|
|
|
|
if (kdb_dbbe != NULL && kdb_active == 0) {
|
|
if (msg != NULL)
|
|
printf("KDB: enter: %s\n", msg);
|
|
kdb_why = why;
|
|
breakpoint();
|
|
kdb_why = KDB_WHY_UNSET;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Initialize the kernel debugger interface.
|
|
*/
|
|
void
|
|
kdb_init(void)
|
|
{
|
|
struct kdb_dbbe *be, **iter;
|
|
int cur_pri, pri;
|
|
|
|
kdb_active = 0;
|
|
kdb_dbbe = NULL;
|
|
cur_pri = -1;
|
|
SET_FOREACH(iter, kdb_dbbe_set) {
|
|
be = *iter;
|
|
pri = (be->dbbe_init != NULL) ? be->dbbe_init() : -1;
|
|
be->dbbe_active = (pri >= 0) ? 0 : -1;
|
|
if (pri > cur_pri) {
|
|
cur_pri = pri;
|
|
kdb_dbbe = be;
|
|
}
|
|
}
|
|
if (kdb_dbbe != NULL) {
|
|
printf("KDB: debugger backends:");
|
|
SET_FOREACH(iter, kdb_dbbe_set) {
|
|
be = *iter;
|
|
if (be->dbbe_active == 0)
|
|
printf(" %s", be->dbbe_name);
|
|
}
|
|
printf("\n");
|
|
printf("KDB: current backend: %s\n",
|
|
kdb_dbbe->dbbe_name);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Handle contexts.
|
|
*/
|
|
void *
|
|
kdb_jmpbuf(jmp_buf new)
|
|
{
|
|
void *old;
|
|
|
|
old = kdb_jmpbufp;
|
|
kdb_jmpbufp = new;
|
|
return (old);
|
|
}
|
|
|
|
void
|
|
kdb_reenter(void)
|
|
{
|
|
|
|
if (!kdb_active || kdb_jmpbufp == NULL)
|
|
return;
|
|
|
|
printf("KDB: reentering\n");
|
|
kdb_backtrace();
|
|
longjmp(kdb_jmpbufp, 1);
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
void
|
|
kdb_reenter_silent(void)
|
|
{
|
|
|
|
if (!kdb_active || kdb_jmpbufp == NULL)
|
|
return;
|
|
|
|
longjmp(kdb_jmpbufp, 1);
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
/*
|
|
* Thread-related support functions.
|
|
*/
|
|
struct pcb *
|
|
kdb_thr_ctx(struct thread *thr)
|
|
{
|
|
#if defined(SMP) && defined(KDB_STOPPEDPCB)
|
|
struct pcpu *pc;
|
|
#endif
|
|
|
|
if (thr == curthread)
|
|
return (&kdb_pcb);
|
|
|
|
#if defined(SMP) && defined(KDB_STOPPEDPCB)
|
|
STAILQ_FOREACH(pc, &cpuhead, pc_allcpu) {
|
|
if (pc->pc_curthread == thr &&
|
|
CPU_ISSET(pc->pc_cpuid, &stopped_cpus))
|
|
return (KDB_STOPPEDPCB(pc));
|
|
}
|
|
#endif
|
|
return (thr->td_pcb);
|
|
}
|
|
|
|
struct thread *
|
|
kdb_thr_first(void)
|
|
{
|
|
struct proc *p;
|
|
struct thread *thr;
|
|
|
|
FOREACH_PROC_IN_SYSTEM(p) {
|
|
if (p->p_flag & P_INMEM) {
|
|
thr = FIRST_THREAD_IN_PROC(p);
|
|
if (thr != NULL)
|
|
return (thr);
|
|
}
|
|
}
|
|
return (NULL);
|
|
}
|
|
|
|
struct thread *
|
|
kdb_thr_from_pid(pid_t pid)
|
|
{
|
|
struct proc *p;
|
|
|
|
FOREACH_PROC_IN_SYSTEM(p) {
|
|
if (p->p_flag & P_INMEM && p->p_pid == pid)
|
|
return (FIRST_THREAD_IN_PROC(p));
|
|
}
|
|
return (NULL);
|
|
}
|
|
|
|
struct thread *
|
|
kdb_thr_lookup(lwpid_t tid)
|
|
{
|
|
struct thread *thr;
|
|
|
|
thr = kdb_thr_first();
|
|
while (thr != NULL && thr->td_tid != tid)
|
|
thr = kdb_thr_next(thr);
|
|
return (thr);
|
|
}
|
|
|
|
struct thread *
|
|
kdb_thr_next(struct thread *thr)
|
|
{
|
|
struct proc *p;
|
|
|
|
p = thr->td_proc;
|
|
thr = TAILQ_NEXT(thr, td_plist);
|
|
do {
|
|
if (thr != NULL)
|
|
return (thr);
|
|
p = LIST_NEXT(p, p_list);
|
|
if (p != NULL && (p->p_flag & P_INMEM))
|
|
thr = FIRST_THREAD_IN_PROC(p);
|
|
} while (p != NULL);
|
|
return (NULL);
|
|
}
|
|
|
|
int
|
|
kdb_thr_select(struct thread *thr)
|
|
{
|
|
if (thr == NULL)
|
|
return (EINVAL);
|
|
kdb_thread = thr;
|
|
kdb_thrctx = kdb_thr_ctx(thr);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Enter the debugger due to a trap.
|
|
*/
|
|
int
|
|
kdb_trap(int type, int code, struct trapframe *tf)
|
|
{
|
|
#ifdef SMP
|
|
cpuset_t other_cpus;
|
|
#endif
|
|
struct kdb_dbbe *be;
|
|
register_t intr;
|
|
int handled;
|
|
int did_stop_cpus;
|
|
|
|
be = kdb_dbbe;
|
|
if (be == NULL || be->dbbe_trap == NULL)
|
|
return (0);
|
|
|
|
/* We reenter the debugger through kdb_reenter(). */
|
|
if (kdb_active)
|
|
return (0);
|
|
|
|
intr = intr_disable();
|
|
|
|
if (!SCHEDULER_STOPPED()) {
|
|
#ifdef SMP
|
|
other_cpus = all_cpus;
|
|
CPU_NAND(&other_cpus, &stopped_cpus);
|
|
CPU_CLR(PCPU_GET(cpuid), &other_cpus);
|
|
stop_cpus_hard(other_cpus);
|
|
#endif
|
|
curthread->td_stopsched = 1;
|
|
did_stop_cpus = 1;
|
|
} else
|
|
did_stop_cpus = 0;
|
|
|
|
kdb_active++;
|
|
|
|
kdb_frame = tf;
|
|
|
|
/* Let MD code do its thing first... */
|
|
kdb_cpu_trap(type, code);
|
|
|
|
makectx(tf, &kdb_pcb);
|
|
kdb_thr_select(curthread);
|
|
|
|
cngrab();
|
|
|
|
for (;;) {
|
|
handled = be->dbbe_trap(type, code);
|
|
if (be == kdb_dbbe)
|
|
break;
|
|
be = kdb_dbbe;
|
|
if (be == NULL || be->dbbe_trap == NULL)
|
|
break;
|
|
printf("Switching to %s back-end\n", be->dbbe_name);
|
|
}
|
|
|
|
cnungrab();
|
|
|
|
kdb_active--;
|
|
|
|
if (did_stop_cpus) {
|
|
curthread->td_stopsched = 0;
|
|
#ifdef SMP
|
|
CPU_AND(&other_cpus, &stopped_cpus);
|
|
restart_cpus(other_cpus);
|
|
#endif
|
|
}
|
|
|
|
intr_restore(intr);
|
|
|
|
return (handled);
|
|
}
|