Messages in this thread | | | Date | Wed, 8 Jun 2022 15:21:42 +0200 | Subject | Re: [PATCH 4/7] KVM: x86: SVM: fix avic_kick_target_vcpus_fast | From | Paolo Bonzini <> |
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On 6/6/22 20:08, Maxim Levitsky wrote: > There are two issues in avic_kick_target_vcpus_fast > > 1. It is legal to issue an IPI request with APIC_DEST_NOSHORT > and a physical destination of 0xFF (or 0xFFFFFFFF in case of x2apic), > which must be treated as a broadcast destination. > > Fix this by explicitly checking for it. > Also don’t use ‘index’ in this case as it gives no new information. > > 2. It is legal to issue a logical IPI request to more than one target. > Index field only provides index in physical id table of first > such target and therefore can't be used before we are sure > that only a single target was addressed. > > Instead, parse the ICRL/ICRH, double check that a unicast interrupt > was requested, and use that info to figure out the physical id > of the target vCPU. > At that point there is no need to use the index field as well. > > > In addition to fixing the above issues, also skip the call to > kvm_apic_match_dest. > > It is possible to do this now, because now as long as AVIC is not > inhibited, it is guaranteed that none of the vCPUs changed their > apic id from its default value. > > > This fixes boot of windows guest with AVIC enabled because it uses > IPI with 0xFF destination and no destination shorthand. > > Fixes: 7223fd2d5338 ("KVM: SVM: Use target APIC ID to complete AVIC IRQs when possible") > Cc: stable@vger.kernel.org > > Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Is it possible to use kvm_intr_is_single_vcpu_fast, or am I missing something?
Series queued, thanks.
Paolo
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