gcov: add support for GCC 10.1

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 <[email protected]> Reported-by: Leon Romanovsky <[email protected]> Signed-off-by: Peter Oberparleiter <[email protected]> Tested-by: Leon Romanovsky <[email protected]> Tested-and-Acked-by: Colin Ian King <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
antonovi · Sep 11, 2020 · 40249c6 · 40249c6
1 parent 581cb3a
commit 40249c6
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Showing 2 changed files with 3 additions and 2 deletions.
diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig
@@ -4,7 +4,6 @@ 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
@@ -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