From d689863c1a60b9936b47a34fa5c3330de374f4fc Mon Sep 17 00:00:00 2001 From: Uros Bizjak Date: Tue, 19 Mar 2024 11:40:14 +0100 Subject: [PATCH] x86/asm: Use %a instead of %P operand modifier in asm templates The "P" asm operand modifier is a x86 target-specific modifier. For x86_64, when used with a symbol reference, the "%P" modifier emits "sym" instead of "sym(%rip)". This property is currently used to issue bare symbol reference. The generic "a" operand modifier should be used instead. The "a" asm operand modifier substitutes a memory reference, with the actual operand treated as address. For x86_64, when a symbol is provided, the "a" modifier emits "sym(%rip)" instead of "sym", enabling shorter %rip-relative addressing. Also note that unlike GCC, clang emits %rip-relative symbol reference with "P" asm operand modifier, so the patch also unifies symbol handling with both compilers. No functional changes intended. Signed-off-by: Uros Bizjak Signed-off-by: Ingo Molnar Cc: Linus Torvalds Cc: Josh Poimboeuf Cc: Ard Biesheuvel Cc: "H. Peter Anvin" Link: https://lore.kernel.org/r/20240319104418.284519-4-ubizjak@gmail.com --- arch/x86/include/asm/cpufeature.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index fa938ed96506d..daae5c6e7d0ed 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -172,7 +172,7 @@ static __always_inline bool _static_cpu_has(u16 bit) ALTERNATIVE_TERNARY("jmp 6f", %c[feature], "", "jmp %l[t_no]") ".pushsection .altinstr_aux,\"ax\"\n" "6:\n" - " testb %[bitnum]," _ASM_RIP(%P[cap_byte]) "\n" + " testb %[bitnum], %a[cap_byte]\n" " jnz %l[t_yes]\n" " jmp %l[t_no]\n" ".popsection\n" -- 2.30.2