From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH v2] KVM: vmx: Advance rip to after an ICEBP instruction.
Date: Mon, 28 Apr 2014 12:18:21 +0200
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References: <1397638971-12840-1-git-send-email-huw@codeweavers.com>
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Cc: Gleb Natapov <gleb@kernel.org>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	Jan Kiszka <jan.kiszka@siemens.com>
To: Huw Davies <huw@codeweavers.com>, kvm <kvm@vger.kernel.org>
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Il 16/04/2014 11:02, Huw Davies ha scritto:
> When entering an exception after an ICEBP, the saved instruction
> pointer should point to after the instruction.
>
> This fixes the bug here: https://bugs.launchpad.net/qemu/+bug/1119686
>
> Signed-off-by: Huw Davies <huw@codeweavers.com>
>
> ---
> v2: Mask off DR6_RESERVED before comparing to zero.
>
>  arch/x86/kvm/vmx.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index 1f68c58..930a0df 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -4841,6 +4841,9 @@ static int handle_exception(struct kvm_vcpu *vcpu)
>  		      (KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP))) {
>  			vcpu->arch.dr6 &= ~15;
>  			vcpu->arch.dr6 |= dr6;
> +			if (!(dr6 & ~DR6_RESERVED)) /* icebp */
> +				skip_emulated_instruction(vcpu);
> +
>  			kvm_queue_exception(vcpu, DB_VECTOR);
>  			return 1;
>  		}
>

This was applied to kvm/next by Marcelo.  Thanks for contributing to KVM!

Paolo