From 1bac3b383a93a4a920ffc57441eb133c78567fbd Mon Sep 17 00:00:00 2001
From: Andi Kleen <ak@suse.de>
Date: Sat, 9 Dec 2006 21:33:36 +0100
Subject: [PATCH] [PATCH] x86: Work around gcc 4.2 over aggressive optimizer
The new PDA code uses a dummy _proxy_pda variable to describe
memory references to the PDA. It is never referenced
in inline assembly, but exists as input/output arguments.
gcc 4.2 in some cases can CSE references to this which causes
unresolved symbols. Define it to zero to avoid this.
Signed-off-by: Andi Kleen <ak@suse.de>
---
arch/i386/kernel/vmlinux.lds.S | 1 +
arch/x86_64/kernel/vmlinux.lds.S | 1 +
2 files changed, 2 insertions(+)
diff --git a/arch/i386/kernel/vmlinux.lds.S b/arch/i386/kernel/vmlinux.lds.S
index 16d3c7133ad79..a53c8b1854b58 100644
--- a/arch/i386/kernel/vmlinux.lds.S
+++ b/arch/i386/kernel/vmlinux.lds.S
@@ -26,6 +26,7 @@ OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386")
OUTPUT_ARCH(i386)
ENTRY(phys_startup_32)
jiffies = jiffies_64;
+_proxy_pda = 0;
PHDRS {
text PT_LOAD FLAGS(5); /* R_E */
diff --git a/arch/x86_64/kernel/vmlinux.lds.S b/arch/x86_64/kernel/vmlinux.lds.S
index 6c417788c54b3..514be5dd23031 100644
--- a/arch/x86_64/kernel/vmlinux.lds.S
+++ b/arch/x86_64/kernel/vmlinux.lds.S
@@ -13,6 +13,7 @@ OUTPUT_FORMAT("elf64-x86-64", "elf64-x86-64", "elf64-x86-64")
OUTPUT_ARCH(i386:x86-64)
ENTRY(phys_startup_64)
jiffies_64 = jiffies;
+_proxy_pda = 0;
PHDRS {
text PT_LOAD FLAGS(5); /* R_E */
data PT_LOAD FLAGS(7); /* RWE */
--
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