releases/2.6.23.10/kvm-vmx-reset-mmu-context-when-entering-real-mode.patch

From stable-bounces@linux.kernel.org Sun Dec  2 03:19:18 2007
From: Eddie Dong <eddie.dong@intel.com>
Date: Sun,  2 Dec 2007 13:18:47 +0200
Subject: KVM: VMX: Reset mmu context when entering real mode
To: stable@kernel.org
Cc: kvm-devel@lists.sourceforge.net, Avi Kivity <avi@qumranet.com>, Eddie Dong <eddie.dong@intel.com>, linux-kernel@vger.kernel.org, Qing He <qing.he@intel.com>
Message-ID: <11965943271835-git-send-email-avi@qumranet.com>


From: Eddie Dong <eddie.dong@intel.com>

patch 8668a3c468ed55d19514117a5a959d91d3d03823 in mainline.

Resetting an SMP guest will force AP enter real mode (RESET) with
paging enabled in protected mode. While current enter_rmode() can
only handle mode switch from nonpaging mode to real mode which leads
to SMP reboot failure.

Fix by reloading the mmu context on entering real mode.

Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 drivers/kvm/mmu.c |    1 +
 drivers/kvm/vmx.c |    1 +
 2 files changed, 2 insertions(+)

--- a/drivers/kvm/mmu.c
+++ b/drivers/kvm/mmu.c
@@ -1066,6 +1066,7 @@ int kvm_mmu_reset_context(struct kvm_vcp
 	destroy_kvm_mmu(vcpu);
 	return init_kvm_mmu(vcpu);
 }
+EXPORT_SYMBOL_GPL(kvm_mmu_reset_context);
 
 int kvm_mmu_load(struct kvm_vcpu *vcpu)
 {
--- a/drivers/kvm/vmx.c
+++ b/drivers/kvm/vmx.c
@@ -957,6 +957,7 @@ static void enter_rmode(struct kvm_vcpu 
 	fix_rmode_seg(VCPU_SREG_GS, &vcpu->rmode.gs);
 	fix_rmode_seg(VCPU_SREG_FS, &vcpu->rmode.fs);
 
+	kvm_mmu_reset_context(vcpu);
 	init_rmode_tss(vcpu->kvm);
 }