linux-kernel - Re: [PATCH v2 7/9] KVM: SVM: keep DR6 synchronized with vcpu->arch.dr6

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Message-ID: <20200507182220.GI228260@xz-x1>
Date:   Thu, 7 May 2020 14:22:20 -0400
From:   Peter Xu <peterx@...hat.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Subject: Re: [PATCH v2 7/9] KVM: SVM: keep DR6 synchronized with
 vcpu->arch.dr6

On Thu, May 07, 2020 at 07:50:09AM -0400, Paolo Bonzini wrote:
> @@ -267,7 +268,7 @@ void enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa,
>  	svm->vmcb->save.rsp = nested_vmcb->save.rsp;
>  	svm->vmcb->save.rip = nested_vmcb->save.rip;
>  	svm->vmcb->save.dr7 = nested_vmcb->save.dr7;
> -	svm->vmcb->save.dr6 = nested_vmcb->save.dr6;
> +	svm->vcpu.arch.dr6  = nested_vmcb->save.dr6;

The rest looks very sane to me, but here I failed to figure out how arch.dr6
finally applied to save.dr6.  I saw it is applied in svm_vcpu_run() in the next
patch, but if that's the case then iiuc this commit may break bisection. Thanks,

-- 
Peter Xu