tree 92cfc8967934a0ff318d176351599a20bcb1004f
parent fd901c95388b3bd5a6f749ed1d677a672b992298
author James Morse <james.morse@arm.com> 1461885532 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> 1461897244 -0700

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 <james.morse@arm.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>