Re: [PATCH v5 00/18] kvm: x86: Support AMD SVM AVIC w/ in-kernel irqchip mode

[Suravee Suthikulpanit]

Ping

Thanks
Suravee

On 1/2/20 5:17 PM, Suravee Suthikulpanit wrote:
> Paolo,
>
> Ping. Would you please let me know your feedback when you get a chance to review this series
>
> Thanks,
> Suravee
>
> On 11/15/19 3:15 AM, Suravee Suthikulpanit wrote:
> > The 'commit 67034bb9dd5e ("KVM: SVM: Add irqchip_split() checks before
> > enabling AVIC")' was introduced to fix miscellaneous boot-hang issues
> > when enable AVIC. This is mainly due to AVIC hardware doest not #vmexit
> > on write to LAPIC EOI register resulting in-kernel PIC and IOAPIC to
> > wait and do not inject new interrupts (e.g. PIT, RTC).
> >
> > This limits AVIC to only work with kernel_irqchip=split mode, which is
> > not currently enabled by default, and also required user-space to
> > support split irqchip model, which might not be the case.
> >
> > The goal of this series is to enable AVIC to work in both irqchip modes,
> > by allowing AVIC to be deactivated temporarily during runtime, and fallback
> > to legacy interrupt injection mode (w/ vINTR and interrupt windows)
> > when needed, and then re-enabled subsequently (a.k.a Dynamic APICv).
> >
> > Similar approach is also used to handle Hyper-V SynIC in the
> > 'commit 5c919412fe61 ("kvm/x86: Hyper-V synthetic interrupt controller")',
> > where APICv is permanently disabled at runtime (currently broken for
> > AVIC, and fixed by this series).
> >
> > This series contains several parts:
> > ÂÂ * Part 1: patch 1,2
> > ÂÂÂÂ Code clean up, refactor, and introduce helper functions
> >
> > ÂÂ * Part 2: patch 3
> > ÂÂÂÂ Introduce APICv deactivate bits to keep track of APICv state
> > ÂÂÂÂ for each vm.
> > ÂÂ * Part 3: patch 4-10
> > ÂÂÂÂ Add support for activate/deactivate APICv at runtime
> >
> > ÂÂ * Part 4: patch 11-14:
> > ÂÂÂÂ Add support for various cases where APICv needs to
> > ÂÂÂÂ be deactivated
> >
> > ÂÂ * Part 5: patch 15-17:
> > ÂÂÂÂ Introduce in-kernel IOAPIC workaround for AVIC EOI
> >
> > ÂÂ * Part 6: path 18
> > ÂÂÂÂ Allow enable AVIC w/ kernel_irqchip=on
> >
> > Pre-requisite Patch:
> > ÂÂ * commit b9c6ff94e43a ("iommu/amd: Re-factor guest virtual APIC (de-)activation code")
> > ÂÂÂÂ (https://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git/commit/
> > ÂÂÂÂÂ ?h=next&id=b9c6ff94e43a0ee053e0c1d983fba1ac4953b762)
> >
> > This series has been tested against v5.3 as following:
> > ÂÂ * Booting Linux, FreeBSD, and Windows Server 2019 VMs upto 240 vcpus
> > ÂÂÂÂ w/ qemu option "kernel-irqchip=on" and "-no-hpet".
> > ÂÂ * Pass-through Intel 10GbE NIC and run netperf in the VM.
> >
> > Changes from V4: (https://lkml.org/lkml/2019/11/1/764)
> > ÂÂ * Rename APICV_DEACT_BIT_xxx to APICV_INHIBIT_REASON_xxxx
> > ÂÂ * Introduce kvm_x86_ops.check_apicv_inhibit_reasons hook
> > ÂÂÂÂ to allow vendors to specify which APICv inhibit reason bits
> > ÂÂÂÂ to support (patch 08/18).
> > ÂÂ * Update comment on kvm_request_apicv_update() no-lock requirement.
> > ÂÂÂÂ (patch 04/18)
> >
> > Suravee Suthikulpanit (18):
> > ÂÂ kvm: x86: Modify kvm_x86_ops.get_enable_apicv() to use struct kvm
> > ÂÂÂÂ parameter
> > ÂÂ kvm: lapic: Introduce APICv update helper function
> > ÂÂ kvm: x86: Introduce APICv inhibit reason bits
> > ÂÂ kvm: x86: Add support for dynamic APICv
> > ÂÂ kvm: x86: Add APICv (de)activate request trace points
> > ÂÂ kvm: x86: svm: Add support to (de)activate posted interrupts
> > ÂÂ svm: Add support for setup/destroy virutal APIC backing page for AVIC
> > ÂÂ kvm: x86: Introduce APICv x86 ops for checking APIC inhibit reasons
> > ÂÂ kvm: x86: Introduce x86 ops hook for pre-update APICv
> > ÂÂ svm: Add support for dynamic APICv
> > ÂÂ kvm: x86: hyperv: Use APICv update request interface
> > ÂÂ svm: Deactivate AVIC when launching guest with nested SVM support
> > ÂÂ svm: Temporary deactivate AVIC during ExtINT handling
> > ÂÂ kvm: i8254: Deactivate APICv when using in-kernel PIT re-injection
> > ÂÂÂÂ mode.
> > ÂÂ kvm: lapic: Clean up APIC predefined macros
> > ÂÂ kvm: ioapic: Refactor kvm_ioapic_update_eoi()
> > ÂÂ kvm: ioapic: Lazy update IOAPIC EOI
> > ÂÂ svm: Allow AVIC with in-kernel irqchip mode
> >
> > Â arch/x86/include/asm/kvm_host.h |Â 19 ++++-
> > Â arch/x86/kvm/hyperv.cÂÂÂÂÂÂÂÂÂÂ |ÂÂ 5 +-
> > Â arch/x86/kvm/i8254.cÂÂÂÂÂÂÂÂÂÂÂ |Â 12 +++
> > Â arch/x86/kvm/ioapic.cÂÂÂÂÂÂÂÂÂÂ | 149 +++++++++++++++++++++++-------------
> > Â arch/x86/kvm/lapic.cÂÂÂÂÂÂÂÂÂÂÂ |Â 35 +++++----
> > Â arch/x86/kvm/lapic.hÂÂÂÂÂÂÂÂÂÂÂ |ÂÂ 2 +
> > Â arch/x86/kvm/svm.cÂÂÂÂÂÂÂÂÂÂÂÂÂ | 164 +++++++++++++++++++++++++++++++++++-----
> > Â arch/x86/kvm/trace.hÂÂÂÂÂÂÂÂÂÂÂ |Â 19 +++++
> > Â arch/x86/kvm/vmx/vmx.cÂÂÂÂÂÂÂÂÂ |Â 12 ++-
> > Â arch/x86/kvm/x86.cÂÂÂÂÂÂÂÂÂÂÂÂÂ |Â 71 ++++++++++++++---
> > Â 10 files changed, 385 insertions(+), 103 deletions(-)