diff options
Diffstat (limited to 'arch/arm64/kernel/stacktrace.c')
| -rw-r--r-- | arch/arm64/kernel/stacktrace.c | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c index ccb6078ed9f2..b947eeffa5b2 100644 --- a/arch/arm64/kernel/stacktrace.c +++ b/arch/arm64/kernel/stacktrace.c @@ -20,6 +20,7 @@ #include <linux/sched.h> #include <linux/stacktrace.h> +#include <asm/irq.h> #include <asm/stacktrace.h> /* @@ -39,17 +40,41 @@ int notrace unwind_frame(struct stackframe *frame) { unsigned long high, low; unsigned long fp = frame->fp; + unsigned long irq_stack_ptr; + + /* + * Use raw_smp_processor_id() to avoid false-positives from + * CONFIG_DEBUG_PREEMPT. get_wchan() calls unwind_frame() on sleeping + * task stacks, we can be pre-empted in this case, so + * {raw_,}smp_processor_id() may give us the wrong value. Sleeping + * tasks can't ever be on an interrupt stack, so regardless of cpu, + * the checks will always fail. + */ + irq_stack_ptr = IRQ_STACK_PTR(raw_smp_processor_id()); low = frame->sp; - high = ALIGN(low, THREAD_SIZE); + /* irq stacks are not THREAD_SIZE aligned */ + if (on_irq_stack(frame->sp, raw_smp_processor_id())) + high = irq_stack_ptr; + else + high = ALIGN(low, THREAD_SIZE) - 0x20; - if (fp < low || fp > high - 0x18 || fp & 0xf) + if (fp < low || fp > high || fp & 0xf) return -EINVAL; frame->sp = fp + 0x10; frame->fp = *(unsigned long *)(fp); frame->pc = *(unsigned long *)(fp + 8); + /* + * Check whether we are going to walk through from interrupt stack + * to task stack. + * If we reach the end of the stack - and its an interrupt stack, + * read the original task stack pointer from the dummy frame. + */ + if (frame->sp == irq_stack_ptr) + frame->sp = IRQ_STACK_TO_TASK_STACK(irq_stack_ptr); + return 0; } |