* H. Peter Anvin <hpa@xxxxxxxxx> wrote: > Needed some head scratching, but then... > > It makes sense for the cross-build: it's building for the host, and a > non-x86 machine isn't doing to have a register named "%rsp". Oh, indeed, sfr is building on powerpc64 I think? > So this needs to be protected from non-kernel use either via __KERNEL__ > or by factoring the basic macros out into a separate file. So something like the below? The exception table stuff is definitely kernel-only. The others could, in principle, be used by tooling as well. Thanks, Ingo =======================> From: Ingo Molnar <mingo@xxxxxxxxxx> Date: Thu, 13 May 2021 13:41:41 +0200 Subject: [PATCH] x86/asm: Make <asm/asm.h> valid on cross-builds as well Stephen Rothwell reported that the objtool cross-build breaks on non-x86 hosts: > tools/arch/x86/include/asm/asm.h:185:24: error: invalid register name for 'current_stack_pointer' > 185 | register unsigned long current_stack_pointer asm(_ASM_SP); > | ^~~~~~~~~~~~~~~~~~~~~ The PowerPC host obviously doesn't know much about x86 register names. Protect the kernel-specific bits of <asm/asm.h>, so that it can be included by tooling and cross-built. Reported-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/include/asm/asm.h | 4 ++++ tools/arch/x86/include/asm/asm.h | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h index 507a37a46027..3ad3da9a7d97 100644 --- a/arch/x86/include/asm/asm.h +++ b/arch/x86/include/asm/asm.h @@ -120,6 +120,8 @@ # define CC_OUT(c) [_cc_ ## c] "=qm" #endif +#ifdef __KERNEL__ + /* Exception table entry */ #ifdef __ASSEMBLY__ # define _ASM_EXTABLE_HANDLE(from, to, handler) \ @@ -186,4 +188,6 @@ register unsigned long current_stack_pointer asm(_ASM_SP); #define ASM_CALL_CONSTRAINT "+r" (current_stack_pointer) #endif /* __ASSEMBLY__ */ +#endif /* __KERNEL__ */ + #endif /* _ASM_X86_ASM_H */ diff --git a/tools/arch/x86/include/asm/asm.h b/tools/arch/x86/include/asm/asm.h index 507a37a46027..3ad3da9a7d97 100644 --- a/tools/arch/x86/include/asm/asm.h +++ b/tools/arch/x86/include/asm/asm.h @@ -120,6 +120,8 @@ # define CC_OUT(c) [_cc_ ## c] "=qm" #endif +#ifdef __KERNEL__ + /* Exception table entry */ #ifdef __ASSEMBLY__ # define _ASM_EXTABLE_HANDLE(from, to, handler) \ @@ -186,4 +188,6 @@ register unsigned long current_stack_pointer asm(_ASM_SP); #define ASM_CALL_CONSTRAINT "+r" (current_stack_pointer) #endif /* __ASSEMBLY__ */ +#endif /* __KERNEL__ */ + #endif /* _ASM_X86_ASM_H */