From 573aaff30ec5eebef21a7346f62ef1dbf394544d Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@redhat.com>
Date: Sun, 5 Dec 2010 14:23:54 -0200
Subject: [PATCH 2/2] KVM: VMX: Return 0 from a failed VMREAD

RH-Author: Avi Kivity <avi@redhat.com>
Message-id: <1291559034-31793-3-git-send-email-avi@redhat.com>
Patchwork-id: 14224
O-Subject: [PATCH RHEL5.5.z 2/2] KVM: VMX: Return 0 from a failed VMREAD
Bugzilla: 661397
RH-Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
RH-Acked-by: Gleb Natapov <gleb@redhat.com>
RH-Acked-by: Jes Sorensen <Jes.Sorensen@redhat.com>

Bugzilla: 608709
Upstream: kvm.git 494e4599

If we execute VMREAD during reboot we'll just skip over it.  Instead of
returning garbage, return 0, which has a much smaller chance of confusing
the code.  Otherwise we risk a flood of debug printk()s which block the
reboot process if a serial console or netconsole is enabled.

Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/vmx.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 arch/x86/kvm/vmx.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 1c67e4f..1131409 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -402,10 +402,10 @@ static inline void ept_sync_individual_addr(u64 eptp, gpa_t gpa)
 
 static unsigned long vmcs_readl(unsigned long field)
 {
-	unsigned long value;
+	unsigned long value = 0;
 
 	asm volatile (__ex(ASM_VMX_VMREAD_RDX_RAX)
-		      : "=a"(value) : "d"(field) : "cc");
+		      : "+a"(value) : "d"(field) : "cc");
 	return value;
 }
 
-- 
1.7.3.2