diff options
| -rw-r--r-- | arch/powerpc/kernel/process.c | 26 | ||||
| -rw-r--r-- | arch/powerpc/kernel/stacktrace.c | 29 |
2 files changed, 49 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 71bad4b6f80d..791bd8ea475d 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -2027,7 +2027,7 @@ int validate_sp(unsigned long sp, struct task_struct *p, EXPORT_SYMBOL(validate_sp); -unsigned long get_wchan(struct task_struct *p) +static unsigned long __get_wchan(struct task_struct *p) { unsigned long ip, sp; int count = 0; @@ -2053,6 +2053,20 @@ unsigned long get_wchan(struct task_struct *p) return 0; } +unsigned long get_wchan(struct task_struct *p) +{ + unsigned long ret; + + if (!try_get_task_stack(p)) + return 0; + + ret = __get_wchan(p); + + put_task_stack(p); + + return ret; +} + static int kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH; void show_stack(struct task_struct *tsk, unsigned long *stack) @@ -2067,9 +2081,13 @@ void show_stack(struct task_struct *tsk, unsigned long *stack) int curr_frame = 0; #endif - sp = (unsigned long) stack; if (tsk == NULL) tsk = current; + + if (!try_get_task_stack(tsk)) + return; + + sp = (unsigned long) stack; if (sp == 0) { if (tsk == current) sp = current_stack_pointer(); @@ -2081,7 +2099,7 @@ void show_stack(struct task_struct *tsk, unsigned long *stack) printk("Call Trace:\n"); do { if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD)) - return; + break; stack = (unsigned long *) sp; newsp = stack[0]; @@ -2121,6 +2139,8 @@ void show_stack(struct task_struct *tsk, unsigned long *stack) sp = newsp; } while (count++ < kstack_depth_to_print); + + put_task_stack(tsk); } #ifdef CONFIG_PPC64 diff --git a/arch/powerpc/kernel/stacktrace.c b/arch/powerpc/kernel/stacktrace.c index cf31ce6c1f53..f958f3bcba04 100644 --- a/arch/powerpc/kernel/stacktrace.c +++ b/arch/powerpc/kernel/stacktrace.c @@ -67,12 +67,17 @@ void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) { unsigned long sp; + if (!try_get_task_stack(tsk)) + return; + if (tsk == current) sp = current_stack_pointer(); else sp = tsk->thread.ksp; save_context_stack(trace, sp, tsk, 0); + + put_task_stack(tsk); } EXPORT_SYMBOL_GPL(save_stack_trace_tsk); @@ -90,9 +95,8 @@ EXPORT_SYMBOL_GPL(save_stack_trace_regs); * * If the task is not 'current', the caller *must* ensure the task is inactive. */ -int -save_stack_trace_tsk_reliable(struct task_struct *tsk, - struct stack_trace *trace) +static int __save_stack_trace_tsk_reliable(struct task_struct *tsk, + struct stack_trace *trace) { unsigned long sp; unsigned long newsp; @@ -197,6 +201,25 @@ save_stack_trace_tsk_reliable(struct task_struct *tsk, } return 0; } + +int save_stack_trace_tsk_reliable(struct task_struct *tsk, + struct stack_trace *trace) +{ + int ret; + + /* + * If the task doesn't have a stack (e.g., a zombie), the stack is + * "reliably" empty. + */ + if (!try_get_task_stack(tsk)) + return 0; + + ret = __save_stack_trace_tsk_reliable(tsk, trace); + + put_task_stack(tsk); + + return ret; +} EXPORT_SYMBOL_GPL(save_stack_trace_tsk_reliable); #endif /* CONFIG_HAVE_RELIABLE_STACKTRACE */ |