[PATCH 4.14 60/94] gcov: add support for GCC 10.1

Greg Kroah-Hartman
2020-09-21T16:40:28Z

From: Peter Oberparleiter <oberpar@linux.ibm.com>

[ Upstream commit 40249c6962075c040fd071339acae524f18bfac9 ]

Using gcov to collect coverage data for kernels compiled with GCC 10.1
causes random malfunctions and kernel crashes. This is the result of a
changed GCOV_COUNTERS value in GCC 10.1 that causes a mismatch between
the layout of the gcov_info structure created by GCC profiling code and
the related structure used by the kernel.

Fix this by updating the in-kernel GCOV_COUNTERS value. Also re-enable
config GCOV_KERNEL for use with GCC 10.

Reported-by: Colin Ian King <colin.king@canonical.com>
Reported-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Tested-by: Leon Romanovsky <leonro@nvidia.com>
Tested-and-Acked-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
kernel/gcov/Kconfig | 1 -
kernel/gcov/gcc_4_7.c | 4 +++-
2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig
index 1d78ed19a3512..1276aabaab550 100644
--- a/kernel/gcov/Kconfig
+++ b/kernel/gcov/Kconfig
@@ -3,7 +3,6 @@ menu "GCOV-based kernel profiling"
config GCOV_KERNEL
bool "Enable gcov-based kernel profiling"
depends on DEBUG_FS
- depends on !CC_IS_GCC || GCC_VERSION < 100000
select CONSTRUCTORS if !UML
default n
---help---
diff --git a/kernel/gcov/gcc_4_7.c b/kernel/gcov/gcc_4_7.c
index ca5e5c0ef8536..5b9e76117ded1 100644
--- a/kernel/gcov/gcc_4_7.c
+++ b/kernel/gcov/gcc_4_7.c
@@ -19,7 +19,9 @@
#include <linux/vmalloc.h>
#include "gcov.h"

-#if (__GNUC__ >= 7)
+#if (__GNUC__ >= 10)
+#define GCOV_COUNTERS 8
+#elif (__GNUC__ >= 7)
#define GCOV_COUNTERS 9
#elif (__GNUC__ > 5) || (__GNUC__ == 5 && __GNUC_MINOR__ >= 1)
#define GCOV_COUNTERS 10
--
2.25.1