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Diffstat (limited to 'arch/x86/kernel/stacktrace.c')
-rw-r--r--arch/x86/kernel/stacktrace.c42
1 files changed, 14 insertions, 28 deletions
diff --git a/arch/x86/kernel/stacktrace.c b/arch/x86/kernel/stacktrace.c
index 093f2ea5dd56..7627455047c2 100644
--- a/arch/x86/kernel/stacktrace.c
+++ b/arch/x86/kernel/stacktrace.c
@@ -81,16 +81,6 @@ EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
#ifdef CONFIG_HAVE_RELIABLE_STACKTRACE
-#define STACKTRACE_DUMP_ONCE(task) ({ \
- static bool __section(.data.unlikely) __dumped; \
- \
- if (!__dumped) { \
- __dumped = true; \
- WARN_ON(1); \
- show_stack(task, NULL); \
- } \
-})
-
static int __always_inline
__save_stack_trace_reliable(struct stack_trace *trace,
struct task_struct *task)
@@ -99,30 +89,25 @@ __save_stack_trace_reliable(struct stack_trace *trace,
struct pt_regs *regs;
unsigned long addr;
- for (unwind_start(&state, task, NULL, NULL); !unwind_done(&state);
+ for (unwind_start(&state, task, NULL, NULL);
+ !unwind_done(&state) && !unwind_error(&state);
unwind_next_frame(&state)) {
regs = unwind_get_entry_regs(&state, NULL);
if (regs) {
+ /* Success path for user tasks */
+ if (user_mode(regs))
+ goto success;
+
/*
* Kernel mode registers on the stack indicate an
* in-kernel interrupt or exception (e.g., preemption
* or a page fault), which can make frame pointers
* unreliable.
*/
- if (!user_mode(regs))
- return -EINVAL;
- /*
- * The last frame contains the user mode syscall
- * pt_regs. Skip it and finish the unwind.
- */
- unwind_next_frame(&state);
- if (!unwind_done(&state)) {
- STACKTRACE_DUMP_ONCE(task);
+ if (IS_ENABLED(CONFIG_FRAME_POINTER))
return -EINVAL;
- }
- break;
}
addr = unwind_get_return_address(&state);
@@ -132,21 +117,22 @@ __save_stack_trace_reliable(struct stack_trace *trace,
* generated code which __kernel_text_address() doesn't know
* about.
*/
- if (!addr) {
- STACKTRACE_DUMP_ONCE(task);
+ if (!addr)
return -EINVAL;
- }
if (save_stack_address(trace, addr, false))
return -EINVAL;
}
/* Check for stack corruption */
- if (unwind_error(&state)) {
- STACKTRACE_DUMP_ONCE(task);
+ if (unwind_error(&state))
+ return -EINVAL;
+
+ /* Success path for non-user tasks, i.e. kthreads and idle tasks */
+ if (!(task->flags & (PF_KTHREAD | PF_IDLE)))
return -EINVAL;
- }
+success:
if (trace->nr_entries < trace->max_entries)
trace->entries[trace->nr_entries++] = ULONG_MAX;