diff options
| author |   Ingo Molnar <mingo@kernel.org> | 2018-01-30 15:08:27 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-01-30 15:08:27 +0100 |
| commit | 7e86548e2cc8d308cb75439480f428137151b0de (patch) | |
| tree | fa3bcdedb64f4642a21080bc2b4ddc69ce2b2285 /kernel/trace/trace_stack.c | |
| parent | x86/speculation: Simplify indirect_branch_prediction_barrier() (diff) | |
| parent | Linux 4.15 (diff) | |
Merge tag 'v4.15' into x86/pti, to be able to merge dependent changes
Time has come to switch PTI development over to a v4.15 base - we'll still
try to make sure that all PTI fixes backport cleanly to v4.14 and earlier.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/trace/trace_stack.c')
| -rw-r--r-- | kernel/trace/trace_stack.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index 719a52a4064a..3c7bfc4bf5e9 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -78,7 +78,7 @@ check_stack(unsigned long ip, unsigned long *stack) { unsigned long this_size, flags; unsigned long *p, *top, *start; static int tracer_frame; - int frame_size = ACCESS_ONCE(tracer_frame); + int frame_size = READ_ONCE(tracer_frame); int i, x; this_size = ((unsigned long)stack) & (THREAD_SIZE-1); @@ -209,6 +209,10 @@ stack_trace_call(unsigned long ip, unsigned long parent_ip, if (__this_cpu_read(disable_stack_tracer) != 1) goto out; + /* If rcu is not watching, then save stack trace can fail */ + if (!rcu_is_watching()) + goto out; + ip += MCOUNT_INSN_SIZE; check_stack(ip, &stack); |