linux-kernel - [PATCH v1 1/1] x86/entry/fred: Push __KERNEL

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Message-ID: <20250822071644.1405268-1-xin@zytor.com>
Date: Fri, 22 Aug 2025 00:16:44 -0700
From: "Xin Li (Intel)" <xin@...or.com>
To: linux-kernel@...r.kernel.org
Cc: luto@...nel.org, tglx@...utronix.de, mingo@...hat.com, bp@...en8.de,
        dave.hansen@...ux.intel.com, x86@...nel.org, hpa@...or.com,
        xin@...or.com
Subject: [PATCH v1 1/1] x86/entry/fred: Push __KERNEL_CS directly

Push __KERNEL_CS directly, rather than moving it into RAX and then
pushing RAX.

Suggested-by: H. Peter Anvin (Intel) <hpa@...or.com>
Signed-off-by: Xin Li (Intel) <xin@...or.com>
---
 arch/x86/entry/entry_64_fred.S | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/entry/entry_64_fred.S b/arch/x86/entry/entry_64_fred.S
index 907bd233c6c1..3c1511feadf7 100644
--- a/arch/x86/entry/entry_64_fred.S
+++ b/arch/x86/entry/entry_64_fred.S
@@ -97,8 +97,7 @@ SYM_FUNC_START(asm_fred_entry_from_kvm)
 	push %rdi			/* fred_ss handed in by the caller */
 	push %rbp
 	pushf
-	mov $__KERNEL_CS, %rax
-	push %rax
+	push $__KERNEL_CS
 
 	/*
 	 * Unlike the IDT event delivery, FRED _always_ pushes an error code

base-commit: 3da01ffe1aeaa0d427ab5235ba735226670a80d9
-- 
2.50.1