From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bastian Blank <bastian@waldi.eu.org>
Subject: [PATCH] xen: Disable stack protector for irq helper
Date: Sun, 4 Oct 2009 20:30:13 +0200
Message-ID: <20091004183013.GA26101@wavehammer.waldi.eu.org>
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To: Ingo Molnar <mingo@redhat.com>
Cc: Xen-devel <xen-devel@lists.xensource.com>, Jeremy Fitzhardinge <jeremy@goop.org>, the arch/x86 maintainers <x86@kernel.org>, Stable Kernel <stable@kernel.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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The stack protector needs additional registers on x86_32, which are not
saved in calls to the small paravirt interrupt handlers. This leads to
early crashes as registers are overwritten and not saved by the caller
as instructed.

Signed-off-by: Bastian Blank <waldi@debian.org>

diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
index 3bb4fc2..ac19398 100644
--- a/arch/x86/xen/Makefile
+++ b/arch/x86/xen/Makefile
@@ -5,9 +5,9 @@
 CFLAGS_REMOVE_irq.o = -pg
 endif
 
-# Make sure early boot has no stackprotector
 nostackp := $(call cc-option, -fno-stack-protector)
 CFLAGS_enlighten.o		:= $(nostackp)
+CFLAGS_irq.o			:= $(nostackp)
 CFLAGS_mmu.o			:= $(nostackp)
 
 obj-y		:= enlighten.o setup.o multicalls.o mmu.o irq.o \
-- 
Mind your own business, Spock.  I'm sick of your halfbreed interference.