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/*
* 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/export.h>
#include <linux/ptrace.h>
#include <linux/kexec.h>
#include <linux/sysfs.h>
#include <linux/bug.h>
#include <linux/nmi.h>
#include <asm/stacktrace.h>
static char *exception_stack_names[N_EXCEPTION_STACKS] = {
[ DOUBLEFAULT_STACK-1 ] = "#DF",
[ NMI_STACK-1 ] = "NMI",
[ DEBUG_STACK-1 ] = "#DB",
[ MCE_STACK-1 ] = "#MC",
};
static unsigned long exception_stack_sizes[N_EXCEPTION_STACKS] = {
[0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ,
[DEBUG_STACK - 1] = DEBUG_STKSZ
};
void stack_type_str(enum stack_type type, const char **begin, const char **end)
{
BUILD_BUG_ON(N_EXCEPTION_STACKS != 4);
switch (type) {
case STACK_TYPE_IRQ:
*begin = "IRQ";
*end = "EOI";
break;
case STACK_TYPE_EXCEPTION ... STACK_TYPE_EXCEPTION_LAST:
*begin = exception_stack_names[type - STACK_TYPE_EXCEPTION];
*end = "EOE";
break;
default:
*begin = NULL;
*end = NULL;
}
}
static bool in_exception_stack(unsigned long *stack, struct stack_info *info)
{
unsigned long *begin, *end;
struct pt_regs *regs;
unsigned k;
BUILD_BUG_ON(N_EXCEPTION_STACKS != 4);
for (k = 0; k < N_EXCEPTION_STACKS; k++) {
end = (unsigned long *)raw_cpu_ptr(&orig_ist)->ist[k];
begin = end - (exception_stack_sizes[k] / sizeof(long));
regs = (struct pt_regs *)end - 1;
if (stack < begin || stack >= end)
continue;
info->type = STACK_TYPE_EXCEPTION + k;
info->begin = begin;
info->end = end;
info->next_sp = (unsigned long *)regs->sp;
return true;
}
return false;
}
static bool in_irq_stack(unsigned long *stack, struct stack_info *info)
{
unsigned long *end = (unsigned long *)this_cpu_read(irq_stack_ptr);
unsigned long *begin = end - (IRQ_STACK_SIZE / sizeof(long));
/*
* This is a software stack, so 'end' can be a valid stack pointer.
* It just means the stack is empty.
*/
if (stack < begin || stack > end)
return false;
info->type = STACK_TYPE_IRQ;
info->begin = begin;
info->end = end;
/*
* The next stack pointer is the first thing pushed by the entry code
* after switching to the irq stack.
*/
info->next_sp = (unsigned long *)*(end - 1);
return true;
}
int get_stack_info(unsigned long *stack, struct task_struct *task,
struct stack_info *info, unsigned long *visit_mask)
{
if (!stack)
goto unknown;
task = task ? : current;
if (in_task_stack(stack, task, info))
goto recursion_check;
if (task != current)
goto unknown;
if (in_exception_stack(stack, info))
goto recursion_check;
if (in_irq_stack(stack, info))
goto recursion_check;
goto unknown;
recursion_check:
/*
* Make sure we don't iterate through any given stack more than once.
* If it comes up a second time then there's something wrong going on:
* just break out and report an unknown stack type.
*/
if (visit_mask) {
if (*visit_mask & (1UL << info->type))
goto unknown;
*visit_mask |= 1UL << info->type;
}
return 0;
unknown:
info->type = STACK_TYPE_UNKNOWN;
return -EINVAL;
}
void show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
unsigned long *sp, char *log_lvl)
{
unsigned long *irq_stack_end;
unsigned long *irq_stack;
unsigned long *stack;
int i;
if (!try_get_task_stack(task))
return;
irq_stack_end = (unsigned long *)this_cpu_read(irq_stack_ptr);
irq_stack = irq_stack_end - (IRQ_STACK_SIZE / sizeof(long));
sp = sp ? : get_stack_pointer(task, regs);
stack = sp;
for (i = 0; i < kstack_depth_to_print; i++) {
unsigned long word;
if (stack >= irq_stack && stack <= irq_stack_end) {
if (stack == irq_stack_end) {
stack = (unsigned long *) (irq_stack_end[-1]);
pr_cont(" <EOI> ");
}
} else {
if (kstack_end(stack))
break;
}
if (probe_kernel_address(stack, word))
break;
if ((i % STACKSLOTS_PER_LINE) == 0) {
if (i != 0)
pr_cont("\n");
printk("%s %016lx", log_lvl, word);
} else
pr_cont(" %016lx", word);
stack++;
touch_nmi_watchdog();
}
pr_cont("\n");
show_trace_log_lvl(task, regs, sp, log_lvl);
put_task_stack(task);
}
void show_regs(struct pt_regs *regs)
{
int i;
show_regs_print_info(KERN_DEFAULT);
__show_regs(regs, 1);
/*
* 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_DEFAULT "Stack:\n");
show_stack_log_lvl(current, regs, NULL, KERN_DEFAULT);
printk(KERN_DEFAULT "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)) {
pr_cont(" Bad RIP value.");
break;
}
if (ip == (u8 *)regs->ip)
pr_cont("<%02x> ", c);
else
pr_cont("%02x ", c);
}
}
pr_cont("\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;
}
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