1 /* 2 * Copyright (C) 1991, 1992 Linus Torvalds 3 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs 4 */ 5 #include <linux/kallsyms.h> 6 #include <linux/kprobes.h> 7 #include <linux/uaccess.h> 8 #include <linux/hardirq.h> 9 #include <linux/kdebug.h> 10 #include <linux/module.h> 11 #include <linux/ptrace.h> 12 #include <linux/kexec.h> 13 #include <linux/sysfs.h> 14 #include <linux/bug.h> 15 #include <linux/nmi.h> 16 17 #include <asm/stacktrace.h> 18 19 20 void dump_trace(struct task_struct *task, struct pt_regs *regs, 21 unsigned long *stack, unsigned long bp, 22 const struct stacktrace_ops *ops, void *data) 23 { 24 int graph = 0; 25 26 if (!task) 27 task = current; 28 29 if (!stack) { 30 unsigned long dummy; 31 32 stack = &dummy; 33 if (task && task != current) 34 stack = (unsigned long *)task->thread.sp; 35 } 36 37 if (!bp) 38 bp = stack_frame(task, regs); 39 40 for (;;) { 41 struct thread_info *context; 42 43 context = (struct thread_info *) 44 ((unsigned long)stack & (~(THREAD_SIZE - 1))); 45 bp = ops->walk_stack(context, stack, bp, ops, data, NULL, &graph); 46 47 stack = (unsigned long *)context->previous_esp; 48 if (!stack) 49 break; 50 if (ops->stack(data, "IRQ") < 0) 51 break; 52 touch_nmi_watchdog(); 53 } 54 } 55 EXPORT_SYMBOL(dump_trace); 56 57 void 58 show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, 59 unsigned long *sp, unsigned long bp, char *log_lvl) 60 { 61 unsigned long *stack; 62 int i; 63 64 if (sp == NULL) { 65 if (task) 66 sp = (unsigned long *)task->thread.sp; 67 else 68 sp = (unsigned long *)&sp; 69 } 70 71 stack = sp; 72 for (i = 0; i < kstack_depth_to_print; i++) { 73 if (kstack_end(stack)) 74 break; 75 if (i && ((i % STACKSLOTS_PER_LINE) == 0)) 76 pr_cont("\n"); 77 pr_cont(" %08lx", *stack++); 78 touch_nmi_watchdog(); 79 } 80 pr_cont("\n"); 81 show_trace_log_lvl(task, regs, sp, bp, log_lvl); 82 } 83 84 85 void show_regs(struct pt_regs *regs) 86 { 87 int i; 88 89 __show_regs(regs, !user_mode_vm(regs)); 90 91 pr_emerg("Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)\n", 92 TASK_COMM_LEN, current->comm, task_pid_nr(current), 93 current_thread_info(), current, task_thread_info(current)); 94 /* 95 * When in-kernel, we also print out the stack and code at the 96 * time of the fault.. 97 */ 98 if (!user_mode_vm(regs)) { 99 unsigned int code_prologue = code_bytes * 43 / 64; 100 unsigned int code_len = code_bytes; 101 unsigned char c; 102 u8 *ip; 103 104 pr_emerg("Stack:\n"); 105 show_stack_log_lvl(NULL, regs, ®s->sp, 0, KERN_EMERG); 106 107 pr_emerg("Code:"); 108 109 ip = (u8 *)regs->ip - code_prologue; 110 if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) { 111 /* try starting at IP */ 112 ip = (u8 *)regs->ip; 113 code_len = code_len - code_prologue + 1; 114 } 115 for (i = 0; i < code_len; i++, ip++) { 116 if (ip < (u8 *)PAGE_OFFSET || 117 probe_kernel_address(ip, c)) { 118 pr_cont(" Bad EIP value."); 119 break; 120 } 121 if (ip == (u8 *)regs->ip) 122 pr_cont(" <%02x>", c); 123 else 124 pr_cont(" %02x", c); 125 } 126 } 127 pr_cont("\n"); 128 } 129 130 int is_valid_bugaddr(unsigned long ip) 131 { 132 unsigned short ud2; 133 134 if (ip < PAGE_OFFSET) 135 return 0; 136 if (probe_kernel_address((unsigned short *)ip, ud2)) 137 return 0; 138 139 return ud2 == 0x0b0f; 140 } 141