| /* |
| * 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> |
| |
| const char *stack_type_name(enum stack_type type) |
| { |
| if (type == STACK_TYPE_IRQ) |
| return "IRQ"; |
| |
| if (type == STACK_TYPE_SOFTIRQ) |
| return "SOFTIRQ"; |
| |
| return NULL; |
| } |
| |
| static bool in_hardirq_stack(unsigned long *stack, struct stack_info *info) |
| { |
| unsigned long *begin = (unsigned long *)this_cpu_read(hardirq_stack); |
| unsigned long *end = begin + (THREAD_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; |
| |
| /* |
| * See irq_32.c -- the next stack pointer is stored at the beginning of |
| * the stack. |
| */ |
| info->next_sp = (unsigned long *)*begin; |
| |
| return true; |
| } |
| |
| static bool in_softirq_stack(unsigned long *stack, struct stack_info *info) |
| { |
| unsigned long *begin = (unsigned long *)this_cpu_read(softirq_stack); |
| unsigned long *end = begin + (THREAD_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_SOFTIRQ; |
| info->begin = begin; |
| info->end = end; |
| |
| /* |
| * The next stack pointer is stored at the beginning of the stack. |
| * See irq_32.c. |
| */ |
| info->next_sp = (unsigned long *)*begin; |
| |
| 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_hardirq_stack(stack, info)) |
| goto recursion_check; |
| |
| if (in_softirq_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)) { |
| printk_deferred_once(KERN_WARNING "WARNING: stack recursion on stack type %d\n", info->type); |
| goto unknown; |
| } |
| *visit_mask |= 1UL << info->type; |
| } |
| |
| return 0; |
| |
| unknown: |
| info->type = STACK_TYPE_UNKNOWN; |
| return -EINVAL; |
| } |
| |
| void show_regs(struct pt_regs *regs) |
| { |
| int i; |
| |
| show_regs_print_info(KERN_EMERG); |
| __show_regs(regs, !user_mode(regs)); |
| |
| /* |
| * 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; |
| |
| show_trace_log_lvl(current, regs, NULL, KERN_EMERG); |
| |
| pr_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)) { |
| pr_cont(" Bad EIP 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 (ip < PAGE_OFFSET) |
| return 0; |
| if (probe_kernel_address((unsigned short *)ip, ud2)) |
| return 0; |
| |
| return ud2 == 0x0b0f; |
| } |