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SubjectRe: [PATCH 02/11] KVM: VMX: Handle APIC-write offset wrangling in VMX code
>--- a/arch/x86/kvm/vmx/vmx.c
>+++ b/arch/x86/kvm/vmx/vmx.c
>@@ -5302,9 +5302,16 @@ static int handle_apic_eoi_induced(struct kvm_vcpu *vcpu)
> static int handle_apic_write(struct kvm_vcpu *vcpu)
> {
> unsigned long exit_qualification = vmx_get_exit_qual(vcpu);
>- u32 offset = exit_qualification & 0xfff;
>
>- /* APIC-write VM exit is trap-like and thus no need to adjust IP */
>+ /*
>+ * APIC-write VM-Exit is trap-like, KVM doesn't need to advance RIP and
>+ * hardware has done any necessary aliasing, offset adjustments, etc...
>+ * for the access. I.e. the correct value has already been written to
>+ * the vAPIC page for the correct 16-byte chunk. KVM needs only to
>+ * retrieve the register value and emulate the access.
>+ */
>+ u32 offset = exit_qualification & 0xff0;

Can we take this opportunity to remove offset/exit_qualification?
They are used just once.

>+
> kvm_apic_write_nodecode(vcpu, offset);
> return 1;
> }
>--
>2.35.0.263.gb82422642f-goog
>

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