Re: [PATCH] kvm/svm: fix DR interception handling on upcoming AMD CPUs

["Roedel, Joerg" <Joerg.Roedel@amd.com>]

On Tue, Feb 08, 2011 at 07:22:29PM -0500, Andre Przywara wrote:
> Somehow the code line advancing the RIP and checking for exceptions
> got dropped between the post on the ML and the commit.
> Add it again to let guests boot on upcoming AMD CPUs again.
> 
> Reported-by: Joerg Roedel <joerg.roedel@amd.com>
> Signed-off-by: Andre Przywara <andre.przywara@amd.com>
> ---
>  arch/x86/kvm/svm.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index 25bd1bc..be06e58 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -2776,6 +2776,7 @@ static int dr_interception(struct vcpu_svm *svm)
>  		if (!err)
>  			kvm_register_write(&svm->vcpu, reg, val);
>  	}
> +	kvm_complete_insn_gp(&svm->vcpu, err);

Any exception check takes presedence over the intercept. So a call to
skip_emulated_instruction should be sufficient here.

	Joerg

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