2 * Copyright (C) 1991, 1992 Linus Torvalds
3 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
5 #include <linux/kallsyms.h>
6 #include <linux/kprobes.h>
7 #include <linux/uaccess.h>
8 #include <linux/utsname.h>
9 #include <linux/hardirq.h>
10 #include <linux/kdebug.h>
11 #include <linux/module.h>
12 #include <linux/ptrace.h>
13 #include <linux/ftrace.h>
14 #include <linux/kexec.h>
15 #include <linux/bug.h>
16 #include <linux/nmi.h>
17 #include <linux/sysfs.h>
19 #include <asm/stacktrace.h>
22 int panic_on_unrecovered_nmi;
24 unsigned int code_bytes = 64;
25 int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE;
26 static int die_counter;
28 void printk_address(unsigned long address, int reliable)
30 pr_cont(" [<%p>] %s%pB\n",
31 (void *)address, reliable ? "" : "? ", (void *)address);
34 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
36 print_ftrace_graph_addr(unsigned long addr, void *data,
37 const struct stacktrace_ops *ops,
38 struct thread_info *tinfo, int *graph)
40 struct task_struct *task;
41 unsigned long ret_addr;
44 if (addr != (unsigned long)return_to_handler)
48 index = task->curr_ret_stack;
50 if (!task->ret_stack || index < *graph)
54 ret_addr = task->ret_stack[index].ret;
56 ops->address(data, ret_addr, 1);
62 print_ftrace_graph_addr(unsigned long addr, void *data,
63 const struct stacktrace_ops *ops,
64 struct thread_info *tinfo, int *graph)
69 * x86-64 can have up to three kernel stacks:
72 * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
75 static inline int valid_stack_ptr(struct thread_info *tinfo,
76 void *p, unsigned int size, void *end)
80 if (p < end && p >= (end-THREAD_SIZE))
85 return p > t && p < t + THREAD_SIZE - size;
89 print_context_stack(struct thread_info *tinfo,
90 unsigned long *stack, unsigned long bp,
91 const struct stacktrace_ops *ops, void *data,
92 unsigned long *end, int *graph)
94 struct stack_frame *frame = (struct stack_frame *)bp;
96 while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) {
100 if (__kernel_text_address(addr)) {
101 if ((unsigned long) stack == bp + sizeof(long)) {
102 ops->address(data, addr, 1);
103 frame = frame->next_frame;
104 bp = (unsigned long) frame;
106 ops->address(data, addr, 0);
108 print_ftrace_graph_addr(addr, data, ops, tinfo, graph);
114 EXPORT_SYMBOL_GPL(print_context_stack);
117 print_context_stack_bp(struct thread_info *tinfo,
118 unsigned long *stack, unsigned long bp,
119 const struct stacktrace_ops *ops, void *data,
120 unsigned long *end, int *graph)
122 struct stack_frame *frame = (struct stack_frame *)bp;
123 unsigned long *ret_addr = &frame->return_address;
125 while (valid_stack_ptr(tinfo, ret_addr, sizeof(*ret_addr), end)) {
126 unsigned long addr = *ret_addr;
128 if (!__kernel_text_address(addr))
131 ops->address(data, addr, 1);
132 frame = frame->next_frame;
133 ret_addr = &frame->return_address;
134 print_ftrace_graph_addr(addr, data, ops, tinfo, graph);
137 return (unsigned long)frame;
139 EXPORT_SYMBOL_GPL(print_context_stack_bp);
141 static int print_trace_stack(void *data, char *name)
143 printk("%s <%s> ", (char *)data, name);
148 * Print one address/symbol entries per line.
150 static void print_trace_address(void *data, unsigned long addr, int reliable)
152 touch_nmi_watchdog();
154 printk_address(addr, reliable);
157 static const struct stacktrace_ops print_trace_ops = {
158 .stack = print_trace_stack,
159 .address = print_trace_address,
160 .walk_stack = print_context_stack,
164 show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
165 unsigned long *stack, unsigned long bp, char *log_lvl)
167 printk("%sCall Trace:\n", log_lvl);
168 dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
171 void show_trace(struct task_struct *task, struct pt_regs *regs,
172 unsigned long *stack, unsigned long bp)
174 show_trace_log_lvl(task, regs, stack, bp, "");
177 void show_stack(struct task_struct *task, unsigned long *sp)
179 unsigned long bp = 0;
183 * Stack frames below this one aren't interesting. Don't show them
184 * if we're printing for %current.
186 if (!sp && (!task || task == current)) {
188 bp = stack_frame(current, NULL);
191 show_stack_log_lvl(task, NULL, sp, bp, "");
195 * The architecture-independent dump_stack generator
197 void dump_stack(void)
202 bp = stack_frame(current, NULL);
203 printk("Pid: %d, comm: %.20s %s %s %.*s\n",
204 current->pid, current->comm, print_tainted(),
205 init_utsname()->release,
206 (int)strcspn(init_utsname()->version, " "),
207 init_utsname()->version);
208 show_trace(NULL, NULL, &stack, bp);
210 EXPORT_SYMBOL(dump_stack);
212 static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED;
213 static int die_owner = -1;
214 static unsigned int die_nest_count;
216 unsigned __kprobes long oops_begin(void)
223 /* racy, but better than risking deadlock. */
224 raw_local_irq_save(flags);
225 cpu = smp_processor_id();
226 if (!arch_spin_trylock(&die_lock)) {
227 if (cpu == die_owner)
228 /* nested oops. should stop eventually */;
230 arch_spin_lock(&die_lock);
238 EXPORT_SYMBOL_GPL(oops_begin);
240 void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
242 if (regs && kexec_should_crash(current))
247 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
250 /* Nest count reaches zero, release the lock. */
251 arch_spin_unlock(&die_lock);
252 raw_local_irq_restore(flags);
258 panic("Fatal exception in interrupt");
260 panic("Fatal exception");
264 int __kprobes __die(const char *str, struct pt_regs *regs, long err)
271 "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
272 #ifdef CONFIG_PREEMPT
278 #ifdef CONFIG_DEBUG_PAGEALLOC
279 printk("DEBUG_PAGEALLOC");
282 if (notify_die(DIE_OOPS, str, regs, err,
283 current->thread.trap_nr, SIGSEGV) == NOTIFY_STOP)
289 if (user_mode_vm(regs)) {
291 ss = regs->ss & 0xffff;
293 sp = kernel_stack_pointer(regs);
296 printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip);
297 print_symbol("%s", regs->ip);
298 printk(" SS:ESP %04x:%08lx\n", ss, sp);
300 /* Executive summary in case the oops scrolled away */
301 printk(KERN_ALERT "RIP ");
302 printk_address(regs->ip, 1);
303 printk(" RSP <%016lx>\n", regs->sp);
309 * This is gone through when something in the kernel has done something bad
310 * and is about to be terminated:
312 void die(const char *str, struct pt_regs *regs, long err)
314 unsigned long flags = oops_begin();
317 if (!user_mode_vm(regs))
318 report_bug(regs->ip, regs);
320 if (__die(str, regs, err))
322 oops_end(flags, regs, sig);
325 static int __init kstack_setup(char *s)
333 ret = kstrtoul(s, 0, &val);
336 kstack_depth_to_print = val;
339 early_param("kstack", kstack_setup);
341 static int __init code_bytes_setup(char *s)
349 ret = kstrtoul(s, 0, &val);
354 if (code_bytes > 8192)
359 __setup("code_bytes=", code_bytes_setup);