GCOV kernel embeds counters in the kernel for each line and a part of that embed in __exit text. So we need to keep the __exit text if CONFIG_GCOV_KERNEL=y.
Without this patch, if we discards __exit text (e.g. disables CONFIG_GENERIC_BUG, CONFIG_JUMP_LABEL and CONFIG_SMP_ON_UP) but enables CONFIG_GCOV_PROFILE_FTRACE, ld will error like below on ARM. `.text.exit' referenced in section `.ARM.exidx.text.exit' of kernel/trace/trace_clock.o: defined in discarded section `.text.exit' of kernel/trace/trace_clock.o To fix this issue, we keep __exit when CONFIG_GCOV_KERNEL=y. The reason why not depending CONFIG_GCOV_PROFILE_X, is that the Documentation/dev-tools/gcov.rst says that the developer can enable gcov profile on a file or a directory by customizing Makefile, and that will only depend on CONFIG_GCOV_KERNEL. Signed-off-by: Masami Hiramatsu <mhira...@kernel.org> Reported-by: Arnd Bergmann <a...@arndb.de> --- arch/arm/kernel/vmlinux.lds.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm/kernel/vmlinux.lds.h b/arch/arm/kernel/vmlinux.lds.h index ae5fdff18406..baaacee9f5ce 100644 --- a/arch/arm/kernel/vmlinux.lds.h +++ b/arch/arm/kernel/vmlinux.lds.h @@ -9,7 +9,8 @@ #endif #if (defined(CONFIG_SMP_ON_UP) && !defined(CONFIG_DEBUG_SPINLOCK)) || \ - defined(CONFIG_GENERIC_BUG) || defined(CONFIG_JUMP_LABEL) + defined(CONFIG_GENERIC_BUG) || defined(CONFIG_JUMP_LABEL) || \ + defined(CONFIG_GCOV_KERNEL) #define ARM_EXIT_KEEP(x) x #define ARM_EXIT_DISCARD(x) #else
