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

    KVM: VMX: fix halt emulation while emulating invalid guest sate

to the 3.0-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-vmx-fix-halt-emulation-while-emulating-invalid-guest-sate.patch
and it can be found in the queue-3.0 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 8d76c49e9ffeee839bc0b7a3278a23f99101263e Mon Sep 17 00:00:00 2001
From: Gleb Natapov <[email protected]>
Date: Wed, 8 May 2013 18:38:44 +0300
Subject: KVM: VMX: fix halt emulation while emulating invalid guest sate

From: Gleb Natapov <[email protected]>

commit 8d76c49e9ffeee839bc0b7a3278a23f99101263e upstream.

The invalid guest state emulation loop does not check halt_request
which causes 100% cpu loop while guest is in halt and in invalid
state, but more serious issue is that this leaves halt_request set, so
random instruction emulated by vm86 #GP exit can be interpreted
as halt which causes guest hang. Fix both problems by handling
halt_request in emulation loop.

Reported-by: Tomas Papan <[email protected]>
Tested-by: Tomas Papan <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
Signed-off-by: Gleb Natapov <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 arch/x86/kvm/vmx.c |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3836,6 +3836,12 @@ static int handle_invalid_guest_state(st
                if (err != EMULATE_DONE)
                        return 0;
 
+               if (vcpu->arch.halt_request) {
+                       vcpu->arch.halt_request = 0;
+                       ret = kvm_emulate_halt(vcpu);
+                       goto out;
+               }
+
                if (signal_pending(current))
                        goto out;
                if (need_resched())


Patches currently in stable-queue which might be from [email protected] are

queue-3.0/kvm-vmx-fix-halt-emulation-while-emulating-invalid-guest-sate.patch
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