linux-kernel - [PATCH 5/5] x86: entry, use ENTRY instead of ALIGN+GLOBAL for stub32

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Date:   Wed, 31 May 2017 10:12:43 +0200
From:   Jiri Slaby <jslaby@...e.cz>
To:     mingo@...hat.com
Cc:     tglx@...utronix.de, hpa@...or.com, x86@...nel.org,
        linux-kernel@...r.kernel.org, Jiri Slaby <jslaby@...e.cz>
Subject: [PATCH 5/5] x86: entry, use ENTRY instead of ALIGN+GLOBAL for stub32_clone

ALIGN+GLOBAL is effectively what ENTRY does, so use ENTRY which is
dedicated for global functions.

Note that this is a C-like leaf function -- it has a correct stack
frame, switches one argument and continues by jumping into C. And since
each ENTRY should be balanced by some END*, we add a corresponding
ENDPROC to stub32_clone too.

Besides that, x86's custom GLOBAL macro is going to die very soon.

Signed-off-by: Jiri Slaby <jslaby@...e.cz>
Cc: "H. Peter Anvin" <hpa@...or.com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: Ingo Molnar <mingo@...hat.com>
Cc: <x86@...nel.org>
---
 arch/x86/entry/entry_64_compat.S | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index e1721dafbcb1..aa8a0fa385f3 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -342,8 +342,7 @@ ENTRY(entry_INT80_compat)
 	jmp	restore_regs_and_iret
 END(entry_INT80_compat)
 
-	ALIGN
-GLOBAL(stub32_clone)
+ENTRY(stub32_clone)
 	/*
 	 * The 32-bit clone ABI is: clone(..., int tls_val, int *child_tidptr).
 	 * The 64-bit clone ABI is: clone(..., int *child_tidptr, int tls_val).
@@ -353,3 +352,4 @@ GLOBAL(stub32_clone)
 	 */
 	xchg	%r8, %rcx
 	jmp	sys_clone
+ENDPROC(stub32_clone)
-- 
2.13.0