linux-kernel - [PATCH 1/3] x86/boot/compressed/32: Simplify calculation of output address

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Message-Id: <20200107194436.2166846-1-nivedita@alum.mit.edu>
Date:   Tue,  7 Jan 2020 14:44:34 -0500
From:   Arvind Sankar <nivedita@...m.mit.edu>
To:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        "H. Peter Anvin" <hpa@...or.com>
Cc:     x86@...nel.org, linux-kernel@...r.kernel.org
Subject: [PATCH 1/3] x86/boot/compressed/32: Simplify calculation of output address

Condense the calculation of decompressed kernel start a little.

Signed-off-by: Arvind Sankar <nivedita@...m.mit.edu>
---
 arch/x86/boot/compressed/head_32.S | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index f2dfd6d083ef..1cc55c79d1d0 100644
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -240,11 +240,9 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
 				/* push arguments for extract_kernel: */
 	pushl	$z_output_len	/* decompressed length, end of relocs */
 
-	movl    BP_init_size(%esi), %eax
-	subl    $_end, %eax
-	movl    %ebx, %ebp
-	subl    %eax, %ebp
-	pushl	%ebp		/* output address */
+	leal	_end(%ebx), %eax
+	subl    BP_init_size(%esi), %eax
+	pushl	%eax		/* output address */
 
 	pushl	$z_input_len	/* input_len */
 	leal	input_data(%ebx), %eax
-- 
2.24.1