338 lines
8.2 KiB
C
338 lines
8.2 KiB
C
/*
|
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
|
* Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
|
|
*/
|
|
#include <linux/kallsyms.h>
|
|
#include <linux/kprobes.h>
|
|
#include <linux/uaccess.h>
|
|
#include <linux/hardirq.h>
|
|
#include <linux/kdebug.h>
|
|
#include <linux/module.h>
|
|
#include <linux/ptrace.h>
|
|
#include <linux/kexec.h>
|
|
#include <linux/bug.h>
|
|
#include <linux/nmi.h>
|
|
#include <linux/sysfs.h>
|
|
|
|
#include <asm/stacktrace.h>
|
|
|
|
#include "dumpstack.h"
|
|
|
|
|
|
static char x86_stack_ids[][8] = {
|
|
[DEBUG_STACK - 1] = "#DB",
|
|
[NMI_STACK - 1] = "NMI",
|
|
[DOUBLEFAULT_STACK - 1] = "#DF",
|
|
[STACKFAULT_STACK - 1] = "#SS",
|
|
[MCE_STACK - 1] = "#MC",
|
|
#if DEBUG_STKSZ > EXCEPTION_STKSZ
|
|
[N_EXCEPTION_STACKS ...
|
|
N_EXCEPTION_STACKS + DEBUG_STKSZ / EXCEPTION_STKSZ - 2] = "#DB[?]"
|
|
#endif
|
|
};
|
|
|
|
int x86_is_stack_id(int id, char *name)
|
|
{
|
|
return x86_stack_ids[id - 1] == name;
|
|
}
|
|
|
|
static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
|
|
unsigned *usedp, char **idp)
|
|
{
|
|
unsigned k;
|
|
|
|
/*
|
|
* Iterate over all exception stacks, and figure out whether
|
|
* 'stack' is in one of them:
|
|
*/
|
|
for (k = 0; k < N_EXCEPTION_STACKS; k++) {
|
|
unsigned long end = per_cpu(orig_ist, cpu).ist[k];
|
|
/*
|
|
* Is 'stack' above this exception frame's end?
|
|
* If yes then skip to the next frame.
|
|
*/
|
|
if (stack >= end)
|
|
continue;
|
|
/*
|
|
* Is 'stack' above this exception frame's start address?
|
|
* If yes then we found the right frame.
|
|
*/
|
|
if (stack >= end - EXCEPTION_STKSZ) {
|
|
/*
|
|
* Make sure we only iterate through an exception
|
|
* stack once. If it comes up for the second time
|
|
* then there's something wrong going on - just
|
|
* break out and return NULL:
|
|
*/
|
|
if (*usedp & (1U << k))
|
|
break;
|
|
*usedp |= 1U << k;
|
|
*idp = x86_stack_ids[k];
|
|
return (unsigned long *)end;
|
|
}
|
|
/*
|
|
* If this is a debug stack, and if it has a larger size than
|
|
* the usual exception stacks, then 'stack' might still
|
|
* be within the lower portion of the debug stack:
|
|
*/
|
|
#if DEBUG_STKSZ > EXCEPTION_STKSZ
|
|
if (k == DEBUG_STACK - 1 && stack >= end - DEBUG_STKSZ) {
|
|
unsigned j = N_EXCEPTION_STACKS - 1;
|
|
|
|
/*
|
|
* Black magic. A large debug stack is composed of
|
|
* multiple exception stack entries, which we
|
|
* iterate through now. Dont look:
|
|
*/
|
|
do {
|
|
++j;
|
|
end -= EXCEPTION_STKSZ;
|
|
x86_stack_ids[j][4] = '1' +
|
|
(j - N_EXCEPTION_STACKS);
|
|
} while (stack < end - EXCEPTION_STKSZ);
|
|
if (*usedp & (1U << j))
|
|
break;
|
|
*usedp |= 1U << j;
|
|
*idp = x86_stack_ids[j];
|
|
return (unsigned long *)end;
|
|
}
|
|
#endif
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static inline int
|
|
in_irq_stack(unsigned long *stack, unsigned long *irq_stack,
|
|
unsigned long *irq_stack_end)
|
|
{
|
|
return (stack >= irq_stack && stack < irq_stack_end);
|
|
}
|
|
|
|
/*
|
|
* We are returning from the irq stack and go to the previous one.
|
|
* If the previous stack is also in the irq stack, then bp in the first
|
|
* frame of the irq stack points to the previous, interrupted one.
|
|
* Otherwise we have another level of indirection: We first save
|
|
* the bp of the previous stack, then we switch the stack to the irq one
|
|
* and save a new bp that links to the previous one.
|
|
* (See save_args())
|
|
*/
|
|
static inline unsigned long
|
|
fixup_bp_irq_link(unsigned long bp, unsigned long *stack,
|
|
unsigned long *irq_stack, unsigned long *irq_stack_end)
|
|
{
|
|
#ifdef CONFIG_FRAME_POINTER
|
|
struct stack_frame *frame = (struct stack_frame *)bp;
|
|
|
|
if (!in_irq_stack(stack, irq_stack, irq_stack_end))
|
|
return (unsigned long)frame->next_frame;
|
|
#endif
|
|
return bp;
|
|
}
|
|
|
|
/*
|
|
* x86-64 can have up to three kernel stacks:
|
|
* process stack
|
|
* interrupt stack
|
|
* severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
|
|
*/
|
|
|
|
void dump_trace(struct task_struct *task, struct pt_regs *regs,
|
|
unsigned long *stack, unsigned long bp,
|
|
const struct stacktrace_ops *ops, void *data)
|
|
{
|
|
const unsigned cpu = get_cpu();
|
|
unsigned long *irq_stack_end =
|
|
(unsigned long *)per_cpu(irq_stack_ptr, cpu);
|
|
unsigned used = 0;
|
|
struct thread_info *tinfo;
|
|
int graph = 0;
|
|
|
|
if (!task)
|
|
task = current;
|
|
|
|
if (!stack) {
|
|
unsigned long dummy;
|
|
stack = &dummy;
|
|
if (task && task != current)
|
|
stack = (unsigned long *)task->thread.sp;
|
|
}
|
|
|
|
#ifdef CONFIG_FRAME_POINTER
|
|
if (!bp) {
|
|
if (task == current) {
|
|
/* Grab bp right from our regs */
|
|
get_bp(bp);
|
|
} else {
|
|
/* bp is the last reg pushed by switch_to */
|
|
bp = *(unsigned long *) task->thread.sp;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Print function call entries in all stacks, starting at the
|
|
* current stack address. If the stacks consist of nested
|
|
* exceptions
|
|
*/
|
|
tinfo = task_thread_info(task);
|
|
for (;;) {
|
|
char *id;
|
|
unsigned long *estack_end;
|
|
estack_end = in_exception_stack(cpu, (unsigned long)stack,
|
|
&used, &id);
|
|
|
|
if (estack_end) {
|
|
if (ops->stack(data, id) < 0)
|
|
break;
|
|
|
|
bp = print_context_stack(tinfo, stack, bp, ops,
|
|
data, estack_end, &graph);
|
|
ops->stack(data, "<EOE>");
|
|
/*
|
|
* We link to the next stack via the
|
|
* second-to-last pointer (index -2 to end) in the
|
|
* exception stack:
|
|
*/
|
|
stack = (unsigned long *) estack_end[-2];
|
|
continue;
|
|
}
|
|
if (irq_stack_end) {
|
|
unsigned long *irq_stack;
|
|
irq_stack = irq_stack_end -
|
|
(IRQ_STACK_SIZE - 64) / sizeof(*irq_stack);
|
|
|
|
if (in_irq_stack(stack, irq_stack, irq_stack_end)) {
|
|
if (ops->stack(data, "IRQ") < 0)
|
|
break;
|
|
bp = print_context_stack(tinfo, stack, bp,
|
|
ops, data, irq_stack_end, &graph);
|
|
/*
|
|
* We link to the next stack (which would be
|
|
* the process stack normally) the last
|
|
* pointer (index -1 to end) in the IRQ stack:
|
|
*/
|
|
stack = (unsigned long *) (irq_stack_end[-1]);
|
|
bp = fixup_bp_irq_link(bp, stack, irq_stack,
|
|
irq_stack_end);
|
|
irq_stack_end = NULL;
|
|
ops->stack(data, "EOI");
|
|
continue;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* This handles the process stack:
|
|
*/
|
|
bp = print_context_stack(tinfo, stack, bp, ops, data, NULL, &graph);
|
|
put_cpu();
|
|
}
|
|
EXPORT_SYMBOL(dump_trace);
|
|
|
|
void
|
|
show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
|
|
unsigned long *sp, unsigned long bp, char *log_lvl)
|
|
{
|
|
unsigned long *stack;
|
|
int i;
|
|
const int cpu = smp_processor_id();
|
|
unsigned long *irq_stack_end =
|
|
(unsigned long *)(per_cpu(irq_stack_ptr, cpu));
|
|
unsigned long *irq_stack =
|
|
(unsigned long *)(per_cpu(irq_stack_ptr, cpu) - IRQ_STACK_SIZE);
|
|
|
|
/*
|
|
* debugging aid: "show_stack(NULL, NULL);" prints the
|
|
* back trace for this cpu.
|
|
*/
|
|
|
|
if (sp == NULL) {
|
|
if (task)
|
|
sp = (unsigned long *)task->thread.sp;
|
|
else
|
|
sp = (unsigned long *)&sp;
|
|
}
|
|
|
|
stack = sp;
|
|
for (i = 0; i < kstack_depth_to_print; i++) {
|
|
if (stack >= irq_stack && stack <= irq_stack_end) {
|
|
if (stack == irq_stack_end) {
|
|
stack = (unsigned long *) (irq_stack_end[-1]);
|
|
printk(" <EOI> ");
|
|
}
|
|
} else {
|
|
if (((long) stack & (THREAD_SIZE-1)) == 0)
|
|
break;
|
|
}
|
|
if (i && ((i % STACKSLOTS_PER_LINE) == 0))
|
|
printk("\n%s", log_lvl);
|
|
printk(" %016lx", *stack++);
|
|
touch_nmi_watchdog();
|
|
}
|
|
printk("\n");
|
|
show_trace_log_lvl(task, regs, sp, bp, log_lvl);
|
|
}
|
|
|
|
void show_registers(struct pt_regs *regs)
|
|
{
|
|
int i;
|
|
unsigned long sp;
|
|
const int cpu = smp_processor_id();
|
|
struct task_struct *cur = current;
|
|
|
|
sp = regs->sp;
|
|
printk("CPU %d ", cpu);
|
|
__show_regs(regs, 1);
|
|
printk("Process %s (pid: %d, threadinfo %p, task %p)\n",
|
|
cur->comm, cur->pid, task_thread_info(cur), cur);
|
|
|
|
/*
|
|
* When in-kernel, we also print out the stack and code at the
|
|
* time of the fault..
|
|
*/
|
|
if (!user_mode(regs)) {
|
|
unsigned int code_prologue = code_bytes * 43 / 64;
|
|
unsigned int code_len = code_bytes;
|
|
unsigned char c;
|
|
u8 *ip;
|
|
|
|
printk(KERN_EMERG "Stack:\n");
|
|
show_stack_log_lvl(NULL, regs, (unsigned long *)sp,
|
|
regs->bp, KERN_EMERG);
|
|
|
|
printk(KERN_EMERG "Code: ");
|
|
|
|
ip = (u8 *)regs->ip - code_prologue;
|
|
if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
|
|
/* try starting at IP */
|
|
ip = (u8 *)regs->ip;
|
|
code_len = code_len - code_prologue + 1;
|
|
}
|
|
for (i = 0; i < code_len; i++, ip++) {
|
|
if (ip < (u8 *)PAGE_OFFSET ||
|
|
probe_kernel_address(ip, c)) {
|
|
printk(" Bad RIP value.");
|
|
break;
|
|
}
|
|
if (ip == (u8 *)regs->ip)
|
|
printk("<%02x> ", c);
|
|
else
|
|
printk("%02x ", c);
|
|
}
|
|
}
|
|
printk("\n");
|
|
}
|
|
|
|
int is_valid_bugaddr(unsigned long ip)
|
|
{
|
|
unsigned short ud2;
|
|
|
|
if (__copy_from_user(&ud2, (const void __user *) ip, sizeof(ud2)))
|
|
return 0;
|
|
|
|
return ud2 == 0x0b0f;
|
|
}
|
|
|