diff options
Diffstat (limited to 'arch/x86/kernel/dumpstack_64.c')
| -rw-r--r-- | arch/x86/kernel/dumpstack_64.c | 79 |
1 files changed, 58 insertions, 21 deletions
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c index a071e6be177e..b13af53883aa 100644 --- a/arch/x86/kernel/dumpstack_64.c +++ b/arch/x86/kernel/dumpstack_64.c @@ -10,26 +10,28 @@ #include <linux/module.h> #include <linux/ptrace.h> #include <linux/kexec.h> +#include <linux/sysfs.h> #include <linux/bug.h> #include <linux/nmi.h> -#include <linux/sysfs.h> #include <asm/stacktrace.h> #include "dumpstack.h" +#define N_EXCEPTION_STACKS_END \ + (N_EXCEPTION_STACKS + DEBUG_STKSZ/EXCEPTION_STKSZ - 2) static char x86_stack_ids[][8] = { - [DEBUG_STACK - 1] = "#DB", - [NMI_STACK - 1] = "NMI", - [DOUBLEFAULT_STACK - 1] = "#DF", - [STACKFAULT_STACK - 1] = "#SS", - [MCE_STACK - 1] = "#MC", + [ DEBUG_STACK-1 ] = "#DB", + [ NMI_STACK-1 ] = "NMI", + [ DOUBLEFAULT_STACK-1 ] = "#DF", + [ STACKFAULT_STACK-1 ] = "#SS", + [ MCE_STACK-1 ] = "#MC", #if DEBUG_STKSZ > EXCEPTION_STKSZ - [N_EXCEPTION_STACKS ... - N_EXCEPTION_STACKS + DEBUG_STKSZ / EXCEPTION_STKSZ - 2] = "#DB[?]" + [ N_EXCEPTION_STACKS ... + N_EXCEPTION_STACKS_END ] = "#DB[?]" #endif - }; +}; int x86_is_stack_id(int id, char *name) { @@ -37,7 +39,7 @@ int x86_is_stack_id(int id, char *name) } static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack, - unsigned *usedp, char **idp) + unsigned *usedp, char **idp) { unsigned k; @@ -101,6 +103,35 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack, return NULL; } +static inline int +in_irq_stack(unsigned long *stack, unsigned long *irq_stack, + unsigned long *irq_stack_end) +{ + return (stack >= irq_stack && stack < irq_stack_end); +} + +/* + * We are returning from the irq stack and go to the previous one. + * If the previous stack is also in the irq stack, then bp in the first + * frame of the irq stack points to the previous, interrupted one. + * Otherwise we have another level of indirection: We first save + * the bp of the previous stack, then we switch the stack to the irq one + * and save a new bp that links to the previous one. + * (See save_args()) + */ +static inline unsigned long +fixup_bp_irq_link(unsigned long bp, unsigned long *stack, + unsigned long *irq_stack, unsigned long *irq_stack_end) +{ +#ifdef CONFIG_FRAME_POINTER + struct stack_frame *frame = (struct stack_frame *)bp; + + if (!in_irq_stack(stack, irq_stack, irq_stack_end)) + return (unsigned long)frame->next_frame; +#endif + return bp; +} + /* * x86-64 can have up to three kernel stacks: * process stack @@ -173,7 +204,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs, irq_stack = irq_stack_end - (IRQ_STACK_SIZE - 64) / sizeof(*irq_stack); - if (stack >= irq_stack && stack < irq_stack_end) { + if (in_irq_stack(stack, irq_stack, irq_stack_end)) { if (ops->stack(data, "IRQ") < 0) break; bp = print_context_stack(tinfo, stack, bp, @@ -184,6 +215,8 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs, * pointer (index -1 to end) in the IRQ stack: */ stack = (unsigned long *) (irq_stack_end[-1]); + bp = fixup_bp_irq_link(bp, stack, irq_stack, + irq_stack_end); irq_stack_end = NULL; ops->stack(data, "EOI"); continue; @@ -202,21 +235,24 @@ EXPORT_SYMBOL(dump_trace); void show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, - unsigned long *sp, unsigned long bp, char *log_lvl) + unsigned long *sp, unsigned long bp, char *log_lvl) { + unsigned long *irq_stack_end; + unsigned long *irq_stack; unsigned long *stack; + int cpu; int i; - const int cpu = smp_processor_id(); - unsigned long *irq_stack_end = - (unsigned long *)(per_cpu(irq_stack_ptr, cpu)); - unsigned long *irq_stack = - (unsigned long *)(per_cpu(irq_stack_ptr, cpu) - IRQ_STACK_SIZE); + + preempt_disable(); + cpu = smp_processor_id(); + + irq_stack_end = (unsigned long *)(per_cpu(irq_stack_ptr, cpu)); + irq_stack = (unsigned long *)(per_cpu(irq_stack_ptr, cpu) - IRQ_STACK_SIZE); /* - * debugging aid: "show_stack(NULL, NULL);" prints the - * back trace for this cpu. + * Debugging aid: "show_stack(NULL, NULL);" prints the + * back trace for this cpu: */ - if (sp == NULL) { if (task) sp = (unsigned long *)task->thread.sp; @@ -240,6 +276,8 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, printk(" %016lx", *stack++); touch_nmi_watchdog(); } + preempt_enable(); + printk("\n"); show_trace_log_lvl(task, regs, sp, bp, log_lvl); } @@ -303,4 +341,3 @@ int is_valid_bugaddr(unsigned long ip) return ud2 == 0x0b0f; } - |
