diff options
Diffstat (limited to 'arch/i386/kernel/traps.c')
| -rw-r--r-- | arch/i386/kernel/traps.c | 177 |
1 files changed, 114 insertions, 63 deletions
diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c index 0e498369f35e..7e9edafffd8a 100644 --- a/arch/i386/kernel/traps.c +++ b/arch/i386/kernel/traps.c @@ -11,7 +11,6 @@ * 'Traps.c' handles hardware traps and faults after we have saved some * state in 'asm.s'. */ -#include <linux/config.h> #include <linux/sched.h> #include <linux/kernel.h> #include <linux/string.h> @@ -28,6 +27,7 @@ #include <linux/utsname.h> #include <linux/kprobes.h> #include <linux/kexec.h> +#include <linux/unwind.h> #ifdef CONFIG_EISA #include <linux/ioport.h> @@ -47,7 +47,7 @@ #include <asm/desc.h> #include <asm/i387.h> #include <asm/nmi.h> - +#include <asm/unwind.h> #include <asm/smp.h> #include <asm/arch_hooks.h> #include <asm/kdebug.h> @@ -92,6 +92,11 @@ asmlinkage void spurious_interrupt_bug(void); asmlinkage void machine_check(void); static int kstack_depth_to_print = 24; +#ifdef CONFIG_STACK_UNWIND +static int call_trace = 1; +#else +#define call_trace (-1) +#endif ATOMIC_NOTIFIER_HEAD(i386die_chain); int register_die_notifier(struct notifier_block *nb) @@ -99,13 +104,13 @@ int register_die_notifier(struct notifier_block *nb) vmalloc_sync_all(); return atomic_notifier_chain_register(&i386die_chain, nb); } -EXPORT_SYMBOL(register_die_notifier); +EXPORT_SYMBOL(register_die_notifier); /* used modular by kdb */ int unregister_die_notifier(struct notifier_block *nb) { return atomic_notifier_chain_unregister(&i386die_chain, nb); } -EXPORT_SYMBOL(unregister_die_notifier); +EXPORT_SYMBOL(unregister_die_notifier); /* used modular by kdb */ static inline int valid_stack_ptr(struct thread_info *tinfo, void *p) { @@ -114,28 +119,13 @@ static inline int valid_stack_ptr(struct thread_info *tinfo, void *p) } /* - * Print CONFIG_STACK_BACKTRACE_COLS address/symbol entries per line. + * Print one address/symbol entries per line. */ -static inline int print_addr_and_symbol(unsigned long addr, char *log_lvl, - int printed) +static inline void print_addr_and_symbol(unsigned long addr, char *log_lvl) { - if (!printed) - printk(log_lvl); - -#if CONFIG_STACK_BACKTRACE_COLS == 1 printk(" [<%08lx>] ", addr); -#else - printk(" <%08lx> ", addr); -#endif - print_symbol("%s", addr); - - printed = (printed + 1) % CONFIG_STACK_BACKTRACE_COLS; - if (printed) - printk(" "); - else - printk("\n"); - return printed; + print_symbol("%s\n", addr); } static inline unsigned long print_context_stack(struct thread_info *tinfo, @@ -143,28 +133,44 @@ static inline unsigned long print_context_stack(struct thread_info *tinfo, char *log_lvl) { unsigned long addr; - int printed = 0; /* nr of entries already printed on current line */ #ifdef CONFIG_FRAME_POINTER while (valid_stack_ptr(tinfo, (void *)ebp)) { addr = *(unsigned long *)(ebp + 4); - printed = print_addr_and_symbol(addr, log_lvl, printed); + print_addr_and_symbol(addr, log_lvl); + /* + * break out of recursive entries (such as + * end_of_stack_stop_unwind_function): + */ + if (ebp == *(unsigned long *)ebp) + break; ebp = *(unsigned long *)ebp; } #else while (valid_stack_ptr(tinfo, stack)) { addr = *stack++; if (__kernel_text_address(addr)) - printed = print_addr_and_symbol(addr, log_lvl, printed); + print_addr_and_symbol(addr, log_lvl); } #endif - if (printed) - printk("\n"); - return ebp; } -static void show_trace_log_lvl(struct task_struct *task, +static asmlinkage int +show_trace_unwind(struct unwind_frame_info *info, void *log_lvl) +{ + int n = 0; + + while (unwind(info) == 0 && UNW_PC(info)) { + n++; + print_addr_and_symbol(UNW_PC(info), log_lvl); + if (arch_unw_user_mode(info)) + break; + } + return n; +} + +static void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs, unsigned long *stack, char *log_lvl) { unsigned long ebp; @@ -172,6 +178,36 @@ static void show_trace_log_lvl(struct task_struct *task, if (!task) task = current; + if (call_trace >= 0) { + int unw_ret = 0; + struct unwind_frame_info info; + + if (regs) { + if (unwind_init_frame_info(&info, task, regs) == 0) + unw_ret = show_trace_unwind(&info, log_lvl); + } else if (task == current) + unw_ret = unwind_init_running(&info, show_trace_unwind, log_lvl); + else { + if (unwind_init_blocked(&info, task) == 0) + unw_ret = show_trace_unwind(&info, log_lvl); + } + if (unw_ret > 0) { + if (call_trace == 1 && !arch_unw_user_mode(&info)) { + print_symbol("DWARF2 unwinder stuck at %s\n", + UNW_PC(&info)); + if (UNW_SP(&info) >= PAGE_OFFSET) { + printk("Leftover inexact backtrace:\n"); + stack = (void *)UNW_SP(&info); + } else + printk("Full inexact backtrace again:\n"); + } else if (call_trace >= 1) + return; + else + printk("Full inexact backtrace again:\n"); + } else + printk("Inexact backtrace:\n"); + } + if (task == current) { /* Grab ebp right from our regs */ asm ("movl %%ebp, %0" : "=r" (ebp) : ); @@ -192,13 +228,13 @@ static void show_trace_log_lvl(struct task_struct *task, } } -void show_trace(struct task_struct *task, unsigned long * stack) +void show_trace(struct task_struct *task, struct pt_regs *regs, unsigned long * stack) { - show_trace_log_lvl(task, stack, ""); + show_trace_log_lvl(task, regs, stack, ""); } -static void show_stack_log_lvl(struct task_struct *task, unsigned long *esp, - char *log_lvl) +static void show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, + unsigned long *esp, char *log_lvl) { unsigned long *stack; int i; @@ -219,13 +255,13 @@ static void show_stack_log_lvl(struct task_struct *task, unsigned long *esp, printk("%08lx ", *stack++); } printk("\n%sCall Trace:\n", log_lvl); - show_trace_log_lvl(task, esp, log_lvl); + show_trace_log_lvl(task, regs, esp, log_lvl); } void show_stack(struct task_struct *task, unsigned long *esp) { printk(" "); - show_stack_log_lvl(task, esp, ""); + show_stack_log_lvl(task, NULL, esp, ""); } /* @@ -235,7 +271,7 @@ void dump_stack(void) { unsigned long stack; - show_trace(current, &stack); + show_trace(current, NULL, &stack); } EXPORT_SYMBOL(dump_stack); @@ -268,8 +304,9 @@ void show_registers(struct pt_regs *regs) regs->esi, regs->edi, regs->ebp, esp); printk(KERN_EMERG "ds: %04x es: %04x ss: %04x\n", regs->xds & 0xffff, regs->xes & 0xffff, ss); - printk(KERN_EMERG "Process %s (pid: %d, threadinfo=%p task=%p)", - current->comm, current->pid, current_thread_info(), current); + printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)", + TASK_COMM_LEN, current->comm, current->pid, + current_thread_info(), current, current->thread_info); /* * When in-kernel, we also print out the stack and code at the * time of the fault.. @@ -278,7 +315,7 @@ void show_registers(struct pt_regs *regs) u8 __user *eip; printk("\n" KERN_EMERG "Stack: "); - show_stack_log_lvl(NULL, (unsigned long *)esp, KERN_EMERG); + show_stack_log_lvl(NULL, regs, (unsigned long *)esp, KERN_EMERG); printk(KERN_EMERG "Code: "); @@ -301,35 +338,35 @@ void show_registers(struct pt_regs *regs) static void handle_BUG(struct pt_regs *regs) { + unsigned long eip = regs->eip; unsigned short ud2; - unsigned short line; - char *file; - char c; - unsigned long eip; - - eip = regs->eip; if (eip < PAGE_OFFSET) - goto no_bug; + return; if (__get_user(ud2, (unsigned short __user *)eip)) - goto no_bug; + return; if (ud2 != 0x0b0f) - goto no_bug; - if (__get_user(line, (unsigned short __user *)(eip + 2))) - goto bug; - if (__get_user(file, (char * __user *)(eip + 4)) || - (unsigned long)file < PAGE_OFFSET || __get_user(c, file)) - file = "<bad filename>"; + return; printk(KERN_EMERG "------------[ cut here ]------------\n"); - printk(KERN_EMERG "kernel BUG at %s:%d!\n", file, line); -no_bug: - return; +#ifdef CONFIG_DEBUG_BUGVERBOSE + do { + unsigned short line; + char *file; + char c; + + if (__get_user(line, (unsigned short __user *)(eip + 2))) + break; + if (__get_user(file, (char * __user *)(eip + 4)) || + (unsigned long)file < PAGE_OFFSET || __get_user(c, file)) + file = "<bad filename>"; - /* Here we know it was a BUG but file-n-line is unavailable */ -bug: - printk(KERN_EMERG "Kernel BUG\n"); + printk(KERN_EMERG "kernel BUG at %s:%d!\n", file, line); + return; + } while (0); +#endif + printk(KERN_EMERG "Kernel BUG at [verbose debug info unavailable]\n"); } /* This is gone through when something in the kernel @@ -419,11 +456,9 @@ void die(const char * str, struct pt_regs * regs, long err) if (in_interrupt()) panic("Fatal exception in interrupt"); - if (panic_on_oops) { - printk(KERN_EMERG "Fatal exception: panic in 5 seconds\n"); - ssleep(5); + if (panic_on_oops) panic("Fatal exception"); - } + oops_exit(); do_exit(SIGSEGV); } @@ -1208,3 +1243,19 @@ static int __init kstack_setup(char *s) return 1; } __setup("kstack=", kstack_setup); + +#ifdef CONFIG_STACK_UNWIND +static int __init call_trace_setup(char *s) +{ + if (strcmp(s, "old") == 0) + call_trace = -1; + else if (strcmp(s, "both") == 0) + call_trace = 0; + else if (strcmp(s, "newfallback") == 0) + call_trace = 1; + else if (strcmp(s, "new") == 2) + call_trace = 2; + return 1; +} +__setup("call_trace=", call_trace_setup); +#endif |