KVM: SVM: Ignore writes to Remote Read Data on AVIC write traps
authorSean Christopherson <seanjc@google.com>
Fri, 6 Jan 2023 01:13:02 +0000 (01:13 +0000)
committerPaolo Bonzini <pbonzini@redhat.com>
Fri, 13 Jan 2023 15:45:34 +0000 (10:45 -0500)
commita790e338c7c4971f83e680e59a91d1b91263c8f7
treec48722b803ad76b3c15f5a0a615c7cbf18dead48
parentbbfc7aa62a4a9baff264f1fd91175b6249843984
KVM: SVM: Ignore writes to Remote Read Data on AVIC write traps

Drop writes to APIC_RRR, a.k.a. Remote Read Data Register, on AVIC
unaccelerated write traps.  The register is read-only and isn't emulated
by KVM.  Sending the register through kvm_apic_write_nodecode() will
result in screaming when x2APIC is enabled due to the unexpected failure
to retrieve the MSR (KVM expects that only "legal" accesses will trap).

Fixes: 4d1d7942e36a ("KVM: SVM: Introduce logic to (de)activate x2AVIC mode")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20230106011306.85230-30-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
arch/x86/kvm/svm/avic.c