diff options
Diffstat (limited to 'arch/x86/kernel/dumpstack_64.c')
-rw-r--r-- | arch/x86/kernel/dumpstack_64.c | 117 |
1 files changed, 83 insertions, 34 deletions
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c index addb207..346b1df 100644 --- a/arch/x86/kernel/dumpstack_64.c +++ b/arch/x86/kernel/dumpstack_64.c @@ -104,6 +104,45 @@ in_irq_stack(unsigned long *stack, unsigned long *irq_stack, return (stack >= irq_stack && stack < irq_stack_end); } +static const unsigned long irq_stack_size = + (IRQ_STACK_SIZE - 64) / sizeof(unsigned long); + +enum stack_type { + STACK_IS_UNKNOWN, + STACK_IS_NORMAL, + STACK_IS_EXCEPTION, + STACK_IS_IRQ, +}; + +static enum stack_type +analyze_stack(int cpu, struct task_struct *task, + unsigned long *stack, unsigned long **stack_end, char **id) +{ + unsigned long *irq_stack; + unsigned long addr; + unsigned used = 0; + + addr = ((unsigned long)stack & (~(THREAD_SIZE - 1))); + if ((unsigned long)task_stack_page(task) == addr) + return STACK_IS_NORMAL; + + *stack_end = in_exception_stack(cpu, (unsigned long)stack, + &used, id); + if (*stack_end) + return STACK_IS_EXCEPTION; + + *stack_end = (unsigned long *)per_cpu(irq_stack_ptr, cpu); + if (!*stack_end) + return STACK_IS_UNKNOWN; + + irq_stack = *stack_end - irq_stack_size; + + if (in_irq_stack(stack, irq_stack, *stack_end)) + return STACK_IS_IRQ; + + return STACK_IS_UNKNOWN; +} + /* * x86-64 can have up to three kernel stacks: * process stack @@ -116,12 +155,11 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs, const struct stacktrace_ops *ops, void *data) { const unsigned cpu = get_cpu(); - unsigned long *irq_stack_end = - (unsigned long *)per_cpu(irq_stack_ptr, cpu); - unsigned used = 0; struct thread_info *tinfo; - int graph = 0; + unsigned long *irq_stack; unsigned long dummy; + int graph = 0; + int done = 0; if (!task) task = current; @@ -143,49 +181,60 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs, * exceptions */ tinfo = task_thread_info(task); - for (;;) { + while (!done) { + unsigned long *stack_end; + enum stack_type stype; char *id; - unsigned long *estack_end; - estack_end = in_exception_stack(cpu, (unsigned long)stack, - &used, &id); - if (estack_end) { + stype = analyze_stack(cpu, task, stack, &stack_end, &id); + + /* Default finish unless specified to continue */ + done = 1; + + switch (stype) { + + /* Break out early if we are on the thread stack */ + case STACK_IS_NORMAL: + break; + + case STACK_IS_EXCEPTION: + if (ops->stack(data, id) < 0) break; bp = ops->walk_stack(tinfo, stack, bp, ops, - data, estack_end, &graph); + data, stack_end, &graph); ops->stack(data, "<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; - } - if (irq_stack_end) { - unsigned long *irq_stack; - irq_stack = irq_stack_end - - (IRQ_STACK_SIZE - 64) / sizeof(*irq_stack); - - if (in_irq_stack(stack, irq_stack, irq_stack_end)) { - if (ops->stack(data, "IRQ") < 0) - break; - bp = ops->walk_stack(tinfo, stack, bp, - ops, data, irq_stack_end, &graph); - /* - * 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 *) (irq_stack_end[-1]); - irq_stack_end = NULL; - ops->stack(data, "EOI"); - continue; - } + stack = (unsigned long *) stack_end[-2]; + done = 0; + break; + + case STACK_IS_IRQ: + + if (ops->stack(data, "IRQ") < 0) + break; + bp = ops->walk_stack(tinfo, stack, bp, + ops, data, stack_end, &graph); + /* + * 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 *) (stack_end[-1]); + irq_stack = stack_end - irq_stack_size; + ops->stack(data, "EOI"); + done = 0; + break; + + case STACK_IS_UNKNOWN: + ops->stack(data, "UNK"); + break; } - break; } /* |