linux-kernel - [tip: x86/percpu] x86/acpi: Use %rip-relative addressing in wakeup

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Message-ID: <170137899159.398.1084765322792442893.tip-bot2@tip-bot2>
Date:   Thu, 30 Nov 2023 21:16:31 -0000
From:   "tip-bot2 for Uros Bizjak" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     Uros Bizjak <ubizjak@...il.com>, Ingo Molnar <mingo@...nel.org>,
        "Rafael J. Wysocki" <rafael@...nel.org>, x86@...nel.org,
        linux-kernel@...r.kernel.org
Subject: [tip: x86/percpu] x86/acpi: Use %rip-relative addressing in wakeup_64.S

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

Commit-ID:     0978d64f9406122c369d5f46e1eb855646f6c32c
Gitweb:        https://git.kernel.org/tip/0978d64f9406122c369d5f46e1eb855646f6c32c
Author:        Uros Bizjak <ubizjak@...il.com>
AuthorDate:    Fri, 03 Nov 2023 11:48:22 +01:00
Committer:     Ingo Molnar <mingo@...nel.org>
CommitterDate: Thu, 30 Nov 2023 20:09:49 +01:00

x86/acpi: Use %rip-relative addressing in wakeup_64.S

This is a "nice-to-have" change with minor code generation benefits:

 - Instruction with %rip-relative address operand is one byte shorter than
   its absolute address counterpart,

 - it is also compatible with position independent executable (-fpie) builds,

 - it is also consistent with what the compiler emits by default when
   a symbol is accessed.

No functional changes intended.

Signed-off-by: Uros Bizjak <ubizjak@...il.com>
Signed-off-by: Ingo Molnar <mingo@...nel.org>
Acked-by: Rafael J. Wysocki <rafael@...nel.org>
Link: https://lore.kernel.org/r/20231103104900.409470-1-ubizjak@gmail.com
---
 arch/x86/kernel/acpi/wakeup_64.S | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kernel/acpi/wakeup_64.S b/arch/x86/kernel/acpi/wakeup_64.S
index d5d8a35..94ff83f 100644
--- a/arch/x86/kernel/acpi/wakeup_64.S
+++ b/arch/x86/kernel/acpi/wakeup_64.S
@@ -17,7 +17,7 @@
 	 * Hooray, we are in Long 64-bit mode (but still running in low memory)
 	 */
 SYM_FUNC_START(wakeup_long64)
-	movq	saved_magic, %rax
+	movq	saved_magic(%rip), %rax
 	movq	$0x123456789abcdef0, %rdx
 	cmpq	%rdx, %rax
 	je	2f
@@ -33,14 +33,14 @@ SYM_FUNC_START(wakeup_long64)
 	movw	%ax, %es
 	movw	%ax, %fs
 	movw	%ax, %gs
-	movq	saved_rsp, %rsp
+	movq	saved_rsp(%rip), %rsp
 
-	movq	saved_rbx, %rbx
-	movq	saved_rdi, %rdi
-	movq	saved_rsi, %rsi
-	movq	saved_rbp, %rbp
+	movq	saved_rbx(%rip), %rbx
+	movq	saved_rdi(%rip), %rdi
+	movq	saved_rsi(%rip), %rsi
+	movq	saved_rbp(%rip), %rbp
 
-	movq	saved_rip, %rax
+	movq	saved_rip(%rip), %rax
 	ANNOTATE_RETPOLINE_SAFE
 	jmp	*%rax
 SYM_FUNC_END(wakeup_long64)
@@ -72,11 +72,11 @@ SYM_FUNC_START(do_suspend_lowlevel)
 
 	movq	$.Lresume_point, saved_rip(%rip)
 
-	movq	%rsp, saved_rsp
-	movq	%rbp, saved_rbp
-	movq	%rbx, saved_rbx
-	movq	%rdi, saved_rdi
-	movq	%rsi, saved_rsi
+	movq	%rsp, saved_rsp(%rip)
+	movq	%rbp, saved_rbp(%rip)
+	movq	%rbx, saved_rbx(%rip)
+	movq	%rdi, saved_rdi(%rip)
+	movq	%rsi, saved_rsi(%rip)
 
 	addq	$8, %rsp
 	movl	$3, %edi