Patch "KVM: nVMX: do not leak PML full vmexit to L1" has been added to the 4.4-stable tree

Patch "KVM: nVMX: do not leak PML full vmexit to L1" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    KVM: nVMX: do not leak PML full vmexit to L1

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     kvm-nvmx-do-not-leak-pml-full-vmexit-to-l1.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From ab007cc94ff9d82f5a8db8363b3becbd946e58cf Mon Sep 17 00:00:00 2001
From: Ladi Prosek <lprosek@redhat.com>
Date: Fri, 31 Mar 2017 10:19:26 +0200
Subject: KVM: nVMX: do not leak PML full vmexit to L1
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Ladi Prosek <lprosek@redhat.com>

commit ab007cc94ff9d82f5a8db8363b3becbd946e58cf upstream.

The PML feature is not exposed to guests so we should not be forwarding
the vmexit either.

This commit fixes BSOD 0x20001 (HYPERVISOR_ERROR) when running Hyper-V
enabled Windows Server 2016 in L1 on hardware that supports PML.

Fixes: 843e4330573c ("KVM: VMX: Add PML support in VMX")
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/x86/kvm/vmx.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -7838,6 +7838,9 @@ static bool nested_vmx_exit_handled(stru
 		return nested_cpu_has2(vmcs12, SECONDARY_EXEC_XSAVES);
 	case EXIT_REASON_PCOMMIT:
 		return nested_cpu_has2(vmcs12, SECONDARY_EXEC_PCOMMIT);
+	case EXIT_REASON_PML_FULL:
+		/* We don't expose PML support to L1. */
+		return false;
 	default:
 		return true;
 	}


Patches currently in stable-queue which might be from lprosek@redhat.com are

queue-4.4/kvm-nvmx-do-not-leak-pml-full-vmexit-to-l1.patch
queue-4.4/kvm-nvmx-initialize-pml-fields-in-vmcs02.patch