From: Borislav Petkov <b...@suse.de> ... in order to fix the defconfig build:
./arch/x86/include/asm/cacheflush.h: In function ‘l1d_flush_hw’: ./arch/x86/include/asm/cacheflush.h:15:6: error: implicit declaration of \ function ‘static_cpu_has’; did you mean ‘static_key_false’? [-Werror=implicit-function-declaration] 15 | if (static_cpu_has(X86_FEATURE_FLUSH_L1D)) { | ^~~~~~~~~~~~~~ | static_key_false cc1: some warnings being treated as errors ./arch/x86/include/asm/cacheflush.h:16:3: error: implicit declaration of \ function ‘wrmsrl’ [-Werror=implicit-function-declaration] 16 | wrmsrl(MSR_IA32_FLUSH_CMD, L1D_FLUSH); | Fixes: a9210620ec36 ("x86/mm: Optionally flush L1D on context switch") Reported-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Borislav Petkov <b...@suse.de> Cc: Richard Weinberger <rich...@nod.at> Cc: Balbir Singh <sbl...@amazon.com> --- arch/um/include/asm/cacheflush.h | 9 +++++++++ 1 file changed, 9 insertions(+) create mode 100644 arch/um/include/asm/cacheflush.h diff --git a/arch/um/include/asm/cacheflush.h b/arch/um/include/asm/cacheflush.h new file mode 100644 index 000000000000..b9dee9760043 --- /dev/null +++ b/arch/um/include/asm/cacheflush.h @@ -0,0 +1,9 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_UML_CACHEFLUSH_H +#define _ASM_UML_CACHEFLUSH_H + +#undef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE +#include <asm-generic/cacheflush.h> + +static inline int l1d_flush_hw(void) { return -EOPNOTSUPP; } +#endif /* _ASM_UML_CACHEFLUSH_H */ -- 2.21.0