diff options
Diffstat (limited to '')
| -rw-r--r-- | arch/x86_64/kernel/traps.c | 193 |
1 files changed, 152 insertions, 41 deletions
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c index cea335e8746c..79d05c482072 100644 --- a/arch/x86_64/kernel/traps.c +++ b/arch/x86_64/kernel/traps.c @@ -6,15 +6,12 @@ * * Pentium III FXSR, SSE support * Gareth Hughes <gareth@valinux.com>, May 2000 - * - * $Id: traps.c,v 1.36 2002/03/24 11:09:10 ak Exp $ */ /* * 'Traps.c' handles hardware traps and faults after we have saved some * state in 'entry.S'. */ -#include <linux/config.h> #include <linux/sched.h> #include <linux/kernel.h> #include <linux/string.h> @@ -31,6 +28,7 @@ #include <linux/nmi.h> #include <linux/kprobes.h> #include <linux/kexec.h> +#include <linux/unwind.h> #include <asm/system.h> #include <asm/uaccess.h> @@ -41,7 +39,7 @@ #include <asm/i387.h> #include <asm/kdebug.h> #include <asm/processor.h> - +#include <asm/unwind.h> #include <asm/smp.h> #include <asm/pgalloc.h> #include <asm/pda.h> @@ -71,6 +69,7 @@ asmlinkage void machine_check(void); asmlinkage void spurious_interrupt_bug(void); ATOMIC_NOTIFIER_HEAD(die_chain); +EXPORT_SYMBOL(die_chain); int register_die_notifier(struct notifier_block *nb) { @@ -107,31 +106,35 @@ static inline void preempt_conditional_cli(struct pt_regs *regs) preempt_enable_no_resched(); } -static int kstack_depth_to_print = 10; +static int kstack_depth_to_print = 12; +static int call_trace = 1; #ifdef CONFIG_KALLSYMS -#include <linux/kallsyms.h> -int printk_address(unsigned long address) -{ +# include <linux/kallsyms.h> +void printk_address(unsigned long address) +{ unsigned long offset = 0, symsize; const char *symname; char *modname; - char *delim = ":"; + char *delim = ":"; char namebuf[128]; - symname = kallsyms_lookup(address, &symsize, &offset, &modname, namebuf); - if (!symname) - return printk("[<%016lx>]", address); - if (!modname) + symname = kallsyms_lookup(address, &symsize, &offset, + &modname, namebuf); + if (!symname) { + printk(" [<%016lx>]\n", address); + return; + } + if (!modname) modname = delim = ""; - return printk("<%016lx>{%s%s%s%s%+ld}", - address, delim, modname, delim, symname, offset); -} + printk(" [<%016lx>] %s%s%s%s+0x%lx/0x%lx\n", + address, delim, modname, delim, symname, offset, symsize); +} #else -int printk_address(unsigned long address) -{ - return printk("[<%016lx>]", address); -} +void printk_address(unsigned long address) +{ + printk(" [<%016lx>]\n", address); +} #endif static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack, @@ -149,10 +152,22 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack, }; unsigned k; + /* + * Iterate over all exception stacks, and figure out whether + * 'stack' is in one of them: + */ for (k = 0; k < N_EXCEPTION_STACKS; k++) { unsigned long end; + /* + * set 'end' to the end of the exception stack. + */ switch (k + 1) { + /* + * TODO: this block is not needed i think, because + * setup64.c:cpu_init() sets up t->ist[DEBUG_STACK] + * properly too. + */ #if DEBUG_STKSZ > EXCEPTION_STKSZ case DEBUG_STACK: end = cpu_pda(cpu)->debugstack + DEBUG_STKSZ; @@ -162,19 +177,43 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack, end = per_cpu(init_tss, cpu).ist[k]; break; } + /* + * Is 'stack' above this exception frame's end? + * If yes then skip to the next frame. + */ if (stack >= end) continue; + /* + * Is 'stack' above this exception frame's start address? + * If yes then we found the right frame. + */ if (stack >= end - EXCEPTION_STKSZ) { + /* + * Make sure we only iterate through an exception + * stack once. If it comes up for the second time + * then there's something wrong going on - just + * break out and return NULL: + */ if (*usedp & (1U << k)) break; *usedp |= 1U << k; *idp = ids[k]; return (unsigned long *)end; } + /* + * If this is a debug stack, and if it has a larger size than + * the usual exception stacks, then 'stack' might still + * be within the lower portion of the debug stack: + */ #if DEBUG_STKSZ > EXCEPTION_STKSZ if (k == DEBUG_STACK - 1 && stack >= end - DEBUG_STKSZ) { unsigned j = N_EXCEPTION_STACKS - 1; + /* + * Black magic. A large debug stack is composed of + * multiple exception stack entries, which we + * iterate through now. Dont look: + */ do { ++j; end -= EXCEPTION_STKSZ; @@ -191,6 +230,19 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack, return NULL; } +static int show_trace_unwind(struct unwind_frame_info *info, void *context) +{ + int n = 0; + + while (unwind(info) == 0 && UNW_PC(info)) { + n++; + printk_address(UNW_PC(info)); + if (arch_unw_user_mode(info)) + break; + } + return n; +} + /* * x86-64 can have upto three kernel stacks: * process stack @@ -198,25 +250,48 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack, * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack */ -void show_trace(unsigned long *stack) +void show_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long * stack) { const unsigned cpu = safe_smp_processor_id(); unsigned long *irqstack_end = (unsigned long *)cpu_pda(cpu)->irqstackptr; - int i; + int i = 11; unsigned used = 0; - printk("\nCall Trace:"); + printk("\nCall Trace:\n"); + + if (!tsk) + tsk = current; + + if (call_trace >= 0) { + int unw_ret = 0; + struct unwind_frame_info info; + if (regs) { + if (unwind_init_frame_info(&info, tsk, regs) == 0) + unw_ret = show_trace_unwind(&info, NULL); + } else if (tsk == current) + unw_ret = unwind_init_running(&info, show_trace_unwind, NULL); + else { + if (unwind_init_blocked(&info, tsk) == 0) + unw_ret = show_trace_unwind(&info, NULL); + } + if (unw_ret > 0) { + if (call_trace > 0) + return; + printk("Legacy call trace:"); + i = 18; + } + } + + /* + * Print function call entries within a stack. 'cond' is the + * "end of stackframe" condition, that the 'stack++' + * iteration will eventually trigger. + */ #define HANDLE_STACK(cond) \ do while (cond) { \ unsigned long addr = *stack++; \ if (kernel_text_address(addr)) { \ - if (i > 50) { \ - printk("\n "); \ - i = 0; \ - } \ - else \ - i += printk(" "); \ /* \ * If the address is either in the text segment of the \ * kernel, or in the region which contains vmalloc'ed \ @@ -225,20 +300,30 @@ void show_trace(unsigned long *stack) * down the cause of the crash will be able to figure \ * out the call path that was taken. \ */ \ - i += printk_address(addr); \ + printk_address(addr); \ } \ } while (0) - for(i = 11; ; ) { + /* + * Print function call entries in all stacks, starting at the + * current stack address. If the stacks consist of nested + * exceptions + */ + for ( ; ; ) { const char *id; unsigned long *estack_end; estack_end = in_exception_stack(cpu, (unsigned long)stack, &used, &id); if (estack_end) { - i += printk(" <%s>", id); + printk(" <%s>", id); HANDLE_STACK (stack < estack_end); - i += printk(" <EOE>"); + printk(" <EOE>"); + /* + * We link to the next stack via the + * second-to-last pointer (index -2 to end) in the + * exception stack: + */ stack = (unsigned long *) estack_end[-2]; continue; } @@ -248,23 +333,32 @@ void show_trace(unsigned long *stack) (IRQSTACKSIZE - 64) / sizeof(*irqstack); if (stack >= irqstack && stack < irqstack_end) { - i += printk(" <IRQ>"); + printk(" <IRQ>"); HANDLE_STACK (stack < irqstack_end); + /* + * We link to the next stack (which would be + * the process stack normally) the last + * pointer (index -1 to end) in the IRQ stack: + */ stack = (unsigned long *) (irqstack_end[-1]); irqstack_end = NULL; - i += printk(" <EOI>"); + printk(" <EOI>"); continue; } } break; } + /* + * This prints the process stack: + */ HANDLE_STACK (((long) stack & (THREAD_SIZE-1)) != 0); #undef HANDLE_STACK + printk("\n"); } -void show_stack(struct task_struct *tsk, unsigned long * rsp) +static void _show_stack(struct task_struct *tsk, struct pt_regs *regs, unsigned long * rsp) { unsigned long *stack; int i; @@ -294,11 +388,16 @@ void show_stack(struct task_struct *tsk, unsigned long * rsp) break; } if (i && ((i % 4) == 0)) - printk("\n "); - printk("%016lx ", *stack++); + printk("\n"); + printk(" %016lx", *stack++); touch_nmi_watchdog(); } - show_trace((unsigned long *)rsp); + show_trace(tsk, regs, rsp); +} + +void show_stack(struct task_struct *tsk, unsigned long * rsp) +{ + _show_stack(tsk, NULL, rsp); } /* @@ -307,7 +406,7 @@ void show_stack(struct task_struct *tsk, unsigned long * rsp) void dump_stack(void) { unsigned long dummy; - show_trace(&dummy); + show_trace(NULL, NULL, &dummy); } EXPORT_SYMBOL(dump_stack); @@ -334,7 +433,7 @@ void show_registers(struct pt_regs *regs) if (in_kernel) { printk("Stack: "); - show_stack(NULL, (unsigned long*)rsp); + _show_stack(NULL, regs, (unsigned long*)rsp); printk("\nCode: "); if (regs->rip < PAGE_OFFSET) @@ -383,6 +482,7 @@ void out_of_line_bug(void) { BUG(); } +EXPORT_SYMBOL(out_of_line_bug); #endif static DEFINE_SPINLOCK(die_lock); @@ -1012,3 +1112,14 @@ static int __init kstack_setup(char *s) } __setup("kstack=", kstack_setup); +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, "new") == 0) + call_trace = 1; + return 1; +} +__setup("call_trace=", call_trace_setup); |