From bdab42dfc974d15303afbf259f340f374a453974 Mon Sep 17 00:00:00 2001 From: James Morse Date: Thu, 28 Apr 2016 16:18:52 -0700 Subject: [PATCH] kcov: don't trace the code coverage code Kcov causes the compiler to add a call to __sanitizer_cov_trace_pc() in every basic block. Ftrace patches in a call to _mcount() to each function it has annotated. Letting these mechanisms annotate each other is a bad thing. Break the loop by adding 'notrace' to __sanitizer_cov_trace_pc() so that ftrace won't try to patch this code. This patch lets arm64 with KCOV and STACK_TRACER boot. Signed-off-by: James Morse Acked-by: Dmitry Vyukov Cc: Alexander Potapenko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kcov.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/kcov.c b/kernel/kcov.c index 3efbee0834a8..78bed7125515 100644 --- a/kernel/kcov.c +++ b/kernel/kcov.c @@ -43,7 +43,7 @@ struct kcov { * Entry point from instrumented code. * This is called once per basic-block/edge. */ -void __sanitizer_cov_trace_pc(void) +void notrace __sanitizer_cov_trace_pc(void) { struct task_struct *t; enum kcov_mode mode; -- 2.20.1