[PATCH AUTOSEL 5.8 27/29] gcov: add support for GCC 10.1

From: Sasha Levin
Date: Mon Sep 14 2020 - 13:05:41 EST


From: Peter Oberparleiter <oberpar@xxxxxxxxxxxxx>

[ 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@xxxxxxxxxxxxx>
Reported-by: Leon Romanovsky <leonro@xxxxxxxxxx>
Signed-off-by: Peter Oberparleiter <oberpar@xxxxxxxxxxxxx>
Tested-by: Leon Romanovsky <leonro@xxxxxxxxxx>
Tested-and-Acked-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
kernel/gcov/gcc_4_7.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/kernel/gcov/gcc_4_7.c b/kernel/gcov/gcc_4_7.c
index 908fdf5098c32..53c67c87f141b 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