[PATCH AUTOSEL 4.4 5/8] x86, build: use objtool mcount

Sasha Levin
2021-03-02T17:00:06Z

From: Sami Tolvanen <samitolvanen@google.com>

[ Upstream commit 6dafca97803309c3cb5148d449bfa711e41ddef2 ]

Select HAVE_OBJTOOL_MCOUNT if STACK_VALIDATION is selected to use
objtool to generate __mcount_loc sections for dynamic ftrace with
Clang and gcc <5 (later versions of gcc use -mrecord-mcount).

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/x86/Kconfig | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 1bee1c6a9891..2e2ddc864ea9 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -94,6 +94,7 @@ config X86
select HAVE_CONTEXT_TRACKING if X86_64
select HAVE_COPY_THREAD_TLS
select HAVE_C_RECORDMCOUNT
+ select HAVE_OBJTOOL_MCOUNT if STACK_VALIDATION
select HAVE_DEBUG_KMEMLEAK
select HAVE_DEBUG_STACKOVERFLOW
select HAVE_DMA_API_DEBUG
--
2.30.1