linux-kernel - [PATCH 3/3] x86/boot/compressed/64: Use 32-bit move for z_output

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Date:   Tue,  7 Jan 2020 14:44:36 -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 3/3] x86/boot/compressed/64: Use 32-bit move for z_output_len

z_output_len is a 32-bit quantity, it's enough to use a 32-bit move to
load it.

Signed-off-by: Arvind Sankar <nivedita@...m.mit.edu>
---
 arch/x86/boot/compressed/head_64.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index edd29340bcfd..17139c130ac9 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -531,7 +531,7 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
 	leaq	input_data(%rip), %rdx  /* input_data */
 	movl	$z_input_len, %ecx	/* input_len */
 	movq	%rbp, %r8		/* output target address */
-	movq	$z_output_len, %r9	/* decompressed length, end of relocs */
+	movl	$z_output_len, %r9d	/* decompressed length, end of relocs */
 	call	extract_kernel		/* returns kernel location in %rax */
 	popq	%rsi
 
-- 
2.24.1