linux-kernel - [tip: x86/boot] x86/boot/compressed/64: Use LEA to initialize boot stack pointer

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Message-ID: <158150907763.411.16186019828079681497.tip-bot2@tip-bot2>
Date:   Wed, 12 Feb 2020 12:04:37 -0000
From:   "tip-bot2 for Arvind Sankar" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     Arvind Sankar <nivedita@...m.mit.edu>,
        Borislav Petkov <bp@...e.de>, x86 <x86@...nel.org>,
        LKML <linux-kernel@...r.kernel.org>
Subject: [tip: x86/boot] x86/boot/compressed/64: Use LEA to initialize boot
 stack pointer

The following commit has been merged into the x86/boot branch of tip:

Commit-ID:     48bfdb9deffdc6b683feb25e15f4f26aac503501
Gitweb:        https://git.kernel.org/tip/48bfdb9deffdc6b683feb25e15f4f26aac503501
Author:        Arvind Sankar <nivedita@...m.mit.edu>
AuthorDate:    Tue, 07 Jan 2020 14:44:35 -05:00
Committer:     Borislav Petkov <bp@...e.de>
CommitterDate: Wed, 12 Feb 2020 11:11:06 +01:00

x86/boot/compressed/64: Use LEA to initialize boot stack pointer

It's shorter, and it's what is used in every other place, so make it
consistent.

Signed-off-by: Arvind Sankar <nivedita@...m.mit.edu>
Signed-off-by: Borislav Petkov <bp@...e.de>
Link: https://lkml.kernel.org/r/20200107194436.2166846-2-nivedita@alum.mit.edu
---
 arch/x86/boot/compressed/head_64.S | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index 1f1f6c8..d1220de 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -81,9 +81,7 @@ SYM_FUNC_START(startup_32)
 	subl	$1b, %ebp
 
 /* setup a stack and make sure cpu supports long mode. */
-	movl	$boot_stack_end, %eax
-	addl	%ebp, %eax
-	movl	%eax, %esp
+	leal	boot_stack_end(%ebp), %esp
 
 	call	verify_cpu
 	testl	%eax, %eax