Re: [PATCH v3 00/26] KVM: x86: Halt and APICv overhaul

[Paolo Bonzini]

On 12/8/21 02:52, Sean Christopherson wrote:
> Overhaul and cleanup APIC virtualization (Posted Interrupts on Intel VMX,
> AVIC on AMD SVM) to streamline things as much as possible, remove a bunch
> of cruft, and document the lurking gotchas along the way.
>
> Patch 01 is a fix from Paolo that's already been merged but hasn't made
> its way to kvm/queue.  It's included here to avoid a number of conflicts.
>
> Based on kvm/queue, commit 1cf84614b04a ("KVM: x86: Exit to ...")

Queued, thanks; patches 24-26 for 5.16 and the rest for 5.17.

Just one nit: please tune the language to have a little fewer idiomatic 
phrases, as that can be a bit taxing on non-native speakers.  I for one 
enjoy learning a few new words, and it even adds some "personality" to 
the remote interactions, but it probably distracts people that aren't 
too preficient in English.

Paolo

> v3:
>   - Rebase to kvm/queue (and drop non-x86 patches as they've been queued).
>   - Redo AVIC patches, sadly the vcpu_(un)blocking() hooks need to stay.
>   - Add a patch to fix a missing (docuentation-only) barrier in nested
>     posted interrupt delivery. [Paolo]
>   - Collect reviews.
>
> v2:
>   - https://lore.kernel.org/all/20211009021236.4122790-1-seanjc@xxxxxxxxxx/
>   - Collect reviews. [Christian, David]
>   - Add patch to move arm64 WFI functionality out of hooks. [Marc]
>   - Add RISC-V to the fun.
>   - Add all the APICv fun.
>
> v1: https://lkml.kernel.org/r/20210925005528.1145584-1-seanjc@xxxxxxxxxx
>
> Paolo Bonzini (1):
>    KVM: fix avic_set_running for preemptable kernels
>
> Sean Christopherson (25):
>    KVM: nVMX: Ensure vCPU honors event request if posting nested IRQ
>      fails
>    KVM: VMX: Clean up PI pre/post-block WARNs
>    KVM: VMX: Handle PI wakeup shenanigans during vcpu_put/load
>    KVM: Drop unused kvm_vcpu.pre_pcpu field
>    KVM: Move x86 VMX's posted interrupt list_head to vcpu_vmx
>    KVM: VMX: Move preemption timer <=> hrtimer dance to common x86
>    KVM: x86: Unexport LAPIC's switch_to_{hv,sw}_timer() helpers
>    KVM: x86: Remove defunct pre_block/post_block kvm_x86_ops hooks
>    KVM: SVM: Signal AVIC doorbell iff vCPU is in guest mode
>    KVM: SVM: Don't bother checking for "running" AVIC when kicking for
>      IPIs
>    KVM: SVM: Remove unnecessary APICv/AVIC update in vCPU unblocking path
>    KVM: SVM: Use kvm_vcpu_is_blocking() in AVIC load to handle preemption
>    KVM: SVM: Skip AVIC and IRTE updates when loading blocking vCPU
>    iommu/amd: KVM: SVM: Use pCPU to infer IsRun state for IRTE
>    KVM: VMX: Don't do full kick when triggering posted interrupt "fails"
>    KVM: VMX: Wake vCPU when delivering posted IRQ even if vCPU == this
>      vCPU
>    KVM: VMX: Pass desired vector instead of bool for triggering posted
>      IRQ
>    KVM: VMX: Fold fallback path into triggering posted IRQ helper
>    KVM: VMX: Don't do full kick when handling posted interrupt wakeup
>    KVM: SVM: Drop AVIC's intermediate avic_set_running() helper
>    KVM: SVM: Move svm_hardware_setup() and its helpers below svm_x86_ops
>    KVM: SVM: Nullify vcpu_(un)blocking() hooks if AVIC is disabled
>    KVM: x86: Skip APICv update if APICv is disable at the module level
>    KVM: x86: Drop NULL check on kvm_x86_ops.check_apicv_inhibit_reasons
>    KVM: x86: Unexport __kvm_request_apicv_update()
>
>   arch/x86/include/asm/kvm-x86-ops.h |   2 -
>   arch/x86/include/asm/kvm_host.h    |  12 -
>   arch/x86/kvm/hyperv.c              |   3 +
>   arch/x86/kvm/lapic.c               |   2 -
>   arch/x86/kvm/svm/avic.c            | 116 ++++---
>   arch/x86/kvm/svm/svm.c             | 479 ++++++++++++++---------------
>   arch/x86/kvm/svm/svm.h             |  16 +-
>   arch/x86/kvm/vmx/posted_intr.c     | 234 +++++++-------
>   arch/x86/kvm/vmx/posted_intr.h     |   8 +-
>   arch/x86/kvm/vmx/vmx.c             |  66 ++--
>   arch/x86/kvm/vmx/vmx.h             |   3 +
>   arch/x86/kvm/x86.c                 |  41 ++-
>   drivers/iommu/amd/iommu.c          |   6 +-
>   include/linux/amd-iommu.h          |   6 +-
>   include/linux/kvm_host.h           |   3 -
>   virt/kvm/kvm_main.c                |   3 -
>   16 files changed, 510 insertions(+), 490 deletions(-)