Re: [PATCH] x86/boot: Use __ASM_SIZE() to reduce ifdeffery in cpuflags.c
From: H. Peter Anvin
Date: Thu Jul 18 2024 - 02:36:32 EST
On July 17, 2024 11:32:18 PM PDT, Uros Bizjak <ubizjak@xxxxxxxxx> wrote:
>Use __ASM_SIZE() macro to add correct insn suffix to pushf/popf.
>
>Signed-off-by: Uros Bizjak <ubizjak@xxxxxxxxx>
>Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>Cc: Ingo Molnar <mingo@xxxxxxxxxx>
>Cc: Borislav Petkov <bp@xxxxxxxxx>
>Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
>Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
>---
> arch/x86/boot/cpuflags.c | 10 +++-------
> 1 file changed, 3 insertions(+), 7 deletions(-)
>
>diff --git a/arch/x86/boot/cpuflags.c b/arch/x86/boot/cpuflags.c
>index d75237ba7ce9..aacabe431fd5 100644
>--- a/arch/x86/boot/cpuflags.c
>+++ b/arch/x86/boot/cpuflags.c
>@@ -2,6 +2,7 @@
> #include <linux/types.h>
> #include "bitops.h"
>
>+#include <asm/asm.h>
> #include <asm/processor-flags.h>
> #include <asm/required-features.h>
> #include <asm/msr-index.h>
>@@ -36,13 +37,8 @@ static int has_fpu(void)
> * compressed/ directory where it may be 64-bit code, and thus needs
> * to be 'pushfq' or 'popfq' in that case.
> */
>-#ifdef __x86_64__
>-#define PUSHF "pushfq"
>-#define POPF "popfq"
>-#else
>-#define PUSHF "pushfl"
>-#define POPF "popfl"
>-#endif
>+#define PUSHF __ASM_SIZE(pushf)
>+#define POPF __ASM_SIZE(popf)
>
> int has_eflag(unsigned long mask)
> {
Just use pushf/popf. gas hasn't needed that suffix for a long time as far as I know.