Re: [PATCH v2] KVM: vmx: Advance rip to after an ICEBP instruction.

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2014-04-16 11:02, Huw Davies wrote:
> 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;
>  		}
> 

Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>

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