Re: [PATCH] powerpc/lib/xor_vmx: Relax frame size for clang
From: Christophe Leroy <hidden>
Date: 2022-09-07 17:21:43
Also in:
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Le 21/06/2019 à 10:58, Mathieu Malaterre a écrit :
When building with clang-8 the frame size limit is hit:
../arch/powerpc/lib/xor_vmx.c:119:6: error: stack frame size of 1200 bytes in function '__xor_altivec_5' [-Werror,-Wframe-larger-than=]
Follow the same approach as commit 9c87156cce5a ("powerpc/xmon: Relax
frame size for clang") until a proper fix is implemented upstream in
clang and relax requirement for clang.
With Clang 14 I get the following errors, but only with KASAN selected.
CC arch/powerpc/lib/xor_vmx.o
arch/powerpc/lib/xor_vmx.c:95:6: error: stack frame size (1040) exceeds
limit (1024) in '__xor_altivec_4' [-Werror,-Wframe-larger-than]
void __xor_altivec_4(unsigned long bytes,
^
arch/powerpc/lib/xor_vmx.c:124:6: error: stack frame size (1312) exceeds
limit (1024) in '__xor_altivec_5' [-Werror,-Wframe-larger-than]
void __xor_altivec_5(unsigned long bytes,
^
Is this patch still relevant ?
Or should frame size be relaxed when KASAN is selected ? After all the
stack size is multiplied by 2 when we have KASAN, so maybe the warning
limit should be increased as well ?
Thanks
Christophe
quoted hunk ↗ jump to hunk
Link: https://github.com/ClangBuiltLinux/linux/issues/563 Cc: Joel Stanley <joel@jms.id.au> Signed-off-by: Mathieu Malaterre <redacted> --- arch/powerpc/lib/Makefile | 4 ++++ 1 file changed, 4 insertions(+)diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile index c55f9c27bf79..b3f7d64caaf0 100644 --- a/arch/powerpc/lib/Makefile +++ b/arch/powerpc/lib/Makefile@@ -58,5 +58,9 @@ obj-$(CONFIG_FTR_FIXUP_SELFTEST) += feature-fixups-test.o obj-$(CONFIG_ALTIVEC) += xor_vmx.o xor_vmx_glue.o CFLAGS_xor_vmx.o += -maltivec $(call cc-option,-mabi=altivec) +ifdef CONFIG_CC_IS_CLANG +# See https://github.com/ClangBuiltLinux/linux/issues/563 +CFLAGS_xor_vmx.o += -Wframe-larger-than=4096 +endif obj-$(CONFIG_PPC64) += $(obj64-y)