4.19-stable review patch. If anyone has any objections, please let me know.
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From: Tri Vo trong@android.com
commit 2a6c7c367de82951c98a290a21156770f6f82c84 upstream.
x0 is not callee-saved in the PCS. So there is no need to specify -fcall-used-x0.
Clang doesn't currently support -fcall-used flags. This patch will help building the kernel with clang.
Tested-by: Nick Desaulniers ndesaulniers@google.com Acked-by: Will Deacon will.deacon@arm.com Signed-off-by: Tri Vo trong@android.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/arm64/lib/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/arm64/lib/Makefile +++ b/arch/arm64/lib/Makefile @@ -12,7 +12,7 @@ lib-y := clear_user.o delay.o copy_from # when supported by the CPU. Result and argument registers are handled # correctly, based on the function prototype. lib-$(CONFIG_ARM64_LSE_ATOMICS) += atomic_ll_sc.o -CFLAGS_atomic_ll_sc.o := -fcall-used-x0 -ffixed-x1 -ffixed-x2 \ +CFLAGS_atomic_ll_sc.o := -ffixed-x1 -ffixed-x2 \ -ffixed-x3 -ffixed-x4 -ffixed-x5 -ffixed-x6 \ -ffixed-x7 -fcall-saved-x8 -fcall-saved-x9 \ -fcall-saved-x10 -fcall-saved-x11 -fcall-saved-x12 \