linux-kernel - [PATCH 3/4] x86/asm: delete dummy variables in movdir64b()

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Message-ID: <20250307061203.3281-3-adobriyan@gmail.com>
Date: Fri,  7 Mar 2025 09:12:02 +0300
From: Alexey Dobriyan <adobriyan@...il.com>
To: tglx@...utronix.de,
	mingo@...hat.com,
	bp@...en8.de,
	dave.hansen@...ux.intel.com
Cc: x86@...nel.org,
	hpa@...or.com,
	linux-kernel@...r.kernel.org,
	Alexey Dobriyan <adobriyan@...il.com>
Subject: [PATCH 3/4] x86/asm: delete dummy variables in movdir64b()

Cast to pointer-to-array instead.

Signed-off-by: Alexey Dobriyan <adobriyan@...il.com>
---
 arch/x86/include/asm/special_insns.h | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h
index d349aa0f0a83..b24c6c945c38 100644
--- a/arch/x86/include/asm/special_insns.h
+++ b/arch/x86/include/asm/special_insns.h
@@ -215,13 +215,10 @@ static __always_inline void serialize(void)
 /* The dst parameter must be 64-bytes aligned */
 static inline void movdir64b(void *dst, const void *src)
 {
-	const struct { char _[64]; } *__src = src;
-	struct { char _[64]; } *__dst = dst;
-
 	/*
 	 * MOVDIR64B %(rdx), rax.
 	 *
-	 * Both __src and __dst must be memory constraints in order to tell the
+	 * Both src and dst must be memory constraints in order to tell the
 	 * compiler that no other memory accesses should be reordered around
 	 * this one.
 	 *
@@ -230,8 +227,8 @@ static inline void movdir64b(void *dst, const void *src)
 	 * I.e., not the pointers but what they point to, thus the deref'ing '*'.
 	 */
 	asm volatile(".byte 0x66, 0x0f, 0x38, 0xf8, 0x02"
-		     : "+m" (*__dst)
-		     :  "m" (*__src), "a" (__dst), "d" (__src));
+		     : "+m" (*(char(*)[64])dst)
+		     :  "m" (*(const char(*)[64])src), "a" (dst), "d" (src));
 }
 
 static inline void movdir64b_io(void __iomem *dst, const void *src)
-- 
2.45.3