/*
* 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/utsname.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 <asm/stacktrace.h>
int panic_on_unrecovered_nmi;
int kstack_depth_to_print = 24;
static unsigned int code_bytes = 64;
static int die_counter;
void printk_address(unsigned long address, int reliable)
{
printk(" [<%p>] %s%pS\n", (void *) address,
reliable ? "" : "? ", (void *) address);
}
static inline int valid_stack_ptr(struct thread_info *tinfo,
void *p, unsigned int size, void *end)
{
void *t = tinfo;
if (end) {
if (p < end && p >= (end-THREAD_SIZE))
return 1;
else
return 0;
}
return p > t && p < t + THREAD_SIZE - size;
}
/* The form of the top of the frame on the stack */
struct stack_frame {
struct stack_frame *next_frame;
unsigned long return_address;
};
static inline unsigned long
print_context_stack(struct thread_info *tinfo,
unsigned long *stack, unsigned long bp,
const struct stacktrace_ops *ops, void *data,
unsigned long *end)
{
struct stack_frame *frame = (struct stack_frame *)bp;
while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) {
unsigned long addr;
addr = *stack;
if (__kernel_text_address(addr)) {
if ((unsigned long) stack == bp + sizeof(long)) {
ops->address(data, addr, 1);
frame = frame->next_frame;
bp = (unsigned long) frame;
} else {
ops->address(data, addr, bp == 0);
}
}
stack++;
}
return bp;
}
void dump_trace(struct task_struct *task, struct pt_regs *regs,
unsigned long *stack, unsigned long bp,
const struct stacktrace_ops *ops, void *data)
{
if (!task)
task = current;
if (!stack) {
unsigned long dummy;
stack = &dummy;
if (task != current)
stack = (unsigned long *)task->thread.sp;
}
#ifdef CONFIG_FRAME_POINTER
if (!bp) {
if (task == current) {
/* Grab bp right from our regs */
asm("movl %%ebp, %0" : "=r" (bp) :);
} else {
/* bp is the last reg pushed by switch_to */
bp = *(unsigned long *) task->thread.sp;
}
}
#endif
for (;;) {
struct thread_info *context;
context = (struct thread_info *)
((unsigned long)stack & (~(THREAD_SIZE - 1)));
bp = print_context_stack(context, stack, bp, ops, data, NULL);
/*
* Should be after the line below, but somewhere
* in early boot context comes out corrupted and we
* can't reference it:
*/
if (ops->stack(data, "IRQ") < 0)
break;
stack = (unsigned long *)context->previous_esp;
if (!stack)
break;
touch_nmi_watchdog();
}
}
EXPORT_SYMBOL(dump_trace);
static void
print_trace_warning_symbol(void *data, char *msg, unsigned long symbol)
{
printk(data);
print_symbol(msg, symbol);
printk("\n");
}
static void print_trace_warning(void *data, char *msg)
{
printk("%s%s\n", (char *)data, msg);
}
static int print_trace_stack(void *data, char *name)
{
return 0;
}
/*
* Print one address/symbol entries per line.
*/
static void print_trace_address(void *data, unsigned long addr, int reliable)
{
printk("%s [<%08lx>] ", (char *)data, addr);
if (!reliable)
printk("? ");
print_symbol("%s\n", addr);
touch_nmi_watchdog();
}
static const struct stacktrace_ops print_trace_ops = {
.warning = print_trace_warning,
.warning_symbol = print_trace_warning_symbol,
.stack = print_trace_stack,
.address = print_trace_address,
};
static void
show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
unsigned long *stack, unsigned long bp, char *log_lvl)
{
dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
printk("%s =======================\n", log_lvl);
}
void show_trace(struct task_struct *task, struct pt_regs *regs,
unsigned long *stack, unsigned long bp)
{
show_trace_log_lvl(task, regs, stack, bp, "");
}
static 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;
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 (kstack_end(stack))
break;
if (i && ((i % 8) == 0))
printk("\n%s ", log_lvl);
printk("%08lx ", *stack++);
}
printk("\n%sCall Trace:\n", log_lvl);
show_trace_log_lvl(task, regs, sp, bp, log_lvl);
}
void show_stack(struct task_struct *task, unsigned long *sp)
{
printk(" ");
show_stack_log_lvl(task, NULL, sp, 0, "");
}
/*
* The architecture-independent dump_stack generator
*/
void dump_stack(void)
{
unsigned long bp = 0;
unsigned long stack;
#ifdef CONFIG_FRAME_POINTER
if (!bp)
asm("movl %%ebp, %0" : "=r" (bp):);
#endif
printk("Pid: %d, comm: %.20s %s %s %.*s\n",
current->pid, current->comm, print_tainted(),
init_utsname()->release,
(int)strcspn(init_utsname()->version, " "),
init_utsname()->version);
show_trace(current, NULL, &stack, bp);
}
EXPORT_SYMBOL(dump_stack);
void show_registers(struct pt_regs *regs)
{
int i;
print_modules();
__show_regs(regs, 0);
printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)",
TASK_COMM_LEN, current->comm, task_pid_nr(current),
current_thread_info(), current, task_thread_info(current));
/*
* When in-kernel, we also print out the stack and code at the
* time of the fault..
*/
if (!user_mode_vm(regs)) {
unsigned int code_prologue = code_bytes * 43 / 64;
unsigned int code_len = code_bytes;
unsigned char c;
u8 *ip;
printk("\n" KERN_EMERG "Stack: ");
show_stack_log_lvl(NULL, regs, ®s->sp, 0, 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 EIP */
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 EIP 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 (ip < PAGE_OFFSET)
return 0;
if (probe_kernel_address((unsigned short *)ip, ud2))
return 0;
return ud2 == 0x0b0f;
}
static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED;
static int die_owner = -1;
static unsigned int die_nest_count;
unsigned __kprobes long oops_begin(void)
{
unsigned long flags;
oops_enter();
if (die_owner != raw_smp_processor_id()) {
console_verbose();
raw_local_irq_save(flags);
__raw_spin_lock(&die_lock);
die_owner = smp_processor_id();
die_nest_count = 0;
bust_spinlocks(1);
} else {
raw_local_irq_save(flags);
}
die_nest_count++;
return flags;
}
void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
{
bust_spinlocks(0);
die_owner = -1;
add_taint(TAINT_DIE);
__raw_spin_unlock(&die_lock);
raw_local_irq_restore(flags);
if (!regs)
return;
if (kexec_should_crash(current))
crash_kexec(regs);
if (in_interrupt())
panic("Fatal exception in interrupt");
if (panic_on_oops)
panic("Fatal exception");
oops_exit();
do_exit(signr);
}
int __kprobes __die(const char *str, struct pt_regs *regs, long err)
{
unsigned short ss;
unsigned long sp;
printk(KERN_EMERG "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
#ifdef CONFIG_PREEMPT
printk("PREEMPT ");
#endif
#ifdef CONFIG_SMP
printk("SMP ");
#endif
#ifdef CONFIG_DEBUG_PAGEALLOC
printk("DEBUG_PAGEALLOC");
#endif
printk("\n");
if (notify_die(DIE_OOPS, str, regs, err,
current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
return 1;
show_registers(regs);
/* Executive summary in case the oops scrolled away */
sp = (unsigned long) (®s->sp);
savesegment(ss, ss);
if (user_mode(regs)) {
sp = regs->sp;
ss = regs->ss & 0xffff;
}
printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip);
print_symbol("%s", regs->ip);
printk(" SS:ESP %04x:%08lx\n", ss, sp);
return 0;
}
/*
* This is gone through when something in the kernel has done something bad
* and is about to be terminated:
*/
void die(const char *str, struct pt_regs *regs, long err)
{
unsigned long flags = oops_begin();
if (die_nest_count < 3) {
report_bug(regs->ip, regs);
if (__die(str, regs, err))
regs = NULL;
} else {
printk(KERN_EMERG "Recursive die() failure, output suppressed\n");
}
oops_end(flags, regs, SIGSEGV);
}
static DEFINE_SPINLOCK(nmi_print_lock);
void notrace __kprobes
die_nmi(char *str, struct pt_regs *regs, int do_panic)
{
if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
return;
spin_lock(&nmi_print_lock);
/*
* We are in trouble anyway, lets at least try
* to get a message out:
*/
bust_spinlocks(1);
printk(KERN_EMERG "%s", str);
printk(" on CPU%d, ip %08lx, registers:\n",
smp_processor_id(), regs->ip);
show_registers(regs);
if (do_panic)
panic("Non maskable interrupt");
console_silent();
spin_unlock(&nmi_print_lock);
bust_spinlocks(0);
/*
* If we are in kernel we are probably nested up pretty bad
* and might aswell get out now while we still can:
*/
if (!user_mode_vm(regs)) {
current->thread.trap_no = 2;
crash_kexec(regs);
}
do_exit(SIGSEGV);
}
static int __init kstack_setup(char *s)
{
kstack_depth_to_print = simple_strtoul(s, NULL, 0);
return 1;
}
__setup("kstack=", kstack_setup);
static int __init code_bytes_setup(char *s)
{
code_bytes = simple_strtoul(s, NULL, 0);
if (code_bytes > 8192)
code_bytes = 8192;
return 1;
}
__setup("code_bytes=", code_bytes_setup);
