mbox series

[v3,00/11] KVM: VMX: Clean up Hyper-V PV TLB flush

Message ID 20201027212346.23409-1-sean.j.christopherson@intel.com (mailing list archive)
Headers show
Series KVM: VMX: Clean up Hyper-V PV TLB flush | expand

Message

Sean Christopherson Oct. 27, 2020, 9:23 p.m. UTC
Clean up KVM's PV TLB flushing when running with EPT on Hyper-V, i.e. as
a nested VMM.  No real goal in mind other than the sole patch in v1, which
is a minor change to avoid a future mixup when TDX also wants to define
.remote_flush_tlb.  Everything else is opportunistic clean up.

Patch 1 legitimately tested on VMX (no SVM), everything else effectively
build tested only.

v3:
  - Add a patch to pass the root_hpa instead of pgd to vmx_load_mmu_pgd()
    and retrieve the active PCID only when necessary.  [Vitaly]
  - Selectively collects reviews (skipped a few due to changes). [Vitaly]
  - Explicitly invalidate hv_tlb_eptp instead of leaving it valid when
    the mismatch tracker "knows" it's invalid. [Vitaly]
  - Change the last patch to use "hv_root_ept" instead of "hv_tlb_pgd"
    to better reflect what is actually being tracked.

v2: Rewrite everything.
 
Sean Christopherson (11):
  KVM: x86: Get active PCID only when writing a CR3 value
  KVM: VMX: Track common EPTP for Hyper-V's paravirt TLB flush
  KVM: VMX: Stash kvm_vmx in a local variable for Hyper-V paravirt TLB
    flush
  KVM: VMX: Fold Hyper-V EPTP checking into it's only caller
  KVM: VMX: Do Hyper-V TLB flush iff vCPU's EPTP hasn't been flushed
  KVM: VMX: Invalidate hv_tlb_eptp to denote an EPTP mismatch
  KVM: VMX: Don't invalidate hv_tlb_eptp if the new EPTP matches
  KVM: VMX: Explicitly check for hv_remote_flush_tlb when loading pgd
  KVM: VMX: Define Hyper-V paravirt TLB flush fields iff Hyper-V is
    enabled
  KVM: VMX: Skip additional Hyper-V TLB EPTP flushes if one fails
  KVM: VMX: Track root HPA instead of EPTP for paravirt Hyper-V TLB
    flush

 arch/x86/include/asm/kvm_host.h |   4 +-
 arch/x86/kvm/mmu.h              |   2 +-
 arch/x86/kvm/svm/svm.c          |   4 +-
 arch/x86/kvm/vmx/vmx.c          | 134 ++++++++++++++++++--------------
 arch/x86/kvm/vmx/vmx.h          |  19 ++---
 5 files changed, 87 insertions(+), 76 deletions(-)

Comments

Paolo Bonzini Jan. 27, 2021, 6:10 p.m. UTC | #1
On 27/10/20 22:23, Sean Christopherson wrote:
> Clean up KVM's PV TLB flushing when running with EPT on Hyper-V, i.e. as
> a nested VMM.  No real goal in mind other than the sole patch in v1, which
> is a minor change to avoid a future mixup when TDX also wants to define
> .remote_flush_tlb.  Everything else is opportunistic clean up.
> 
> Patch 1 legitimately tested on VMX (no SVM), everything else effectively
> build tested only.
> 
> v3:
>    - Add a patch to pass the root_hpa instead of pgd to vmx_load_mmu_pgd()
>      and retrieve the active PCID only when necessary.  [Vitaly]
>    - Selectively collects reviews (skipped a few due to changes). [Vitaly]
>    - Explicitly invalidate hv_tlb_eptp instead of leaving it valid when
>      the mismatch tracker "knows" it's invalid. [Vitaly]
>    - Change the last patch to use "hv_root_ept" instead of "hv_tlb_pgd"
>      to better reflect what is actually being tracked.
> 
> v2: Rewrite everything.
>   
> Sean Christopherson (11):
>    KVM: x86: Get active PCID only when writing a CR3 value
>    KVM: VMX: Track common EPTP for Hyper-V's paravirt TLB flush
>    KVM: VMX: Stash kvm_vmx in a local variable for Hyper-V paravirt TLB
>      flush
>    KVM: VMX: Fold Hyper-V EPTP checking into it's only caller
>    KVM: VMX: Do Hyper-V TLB flush iff vCPU's EPTP hasn't been flushed
>    KVM: VMX: Invalidate hv_tlb_eptp to denote an EPTP mismatch
>    KVM: VMX: Don't invalidate hv_tlb_eptp if the new EPTP matches
>    KVM: VMX: Explicitly check for hv_remote_flush_tlb when loading pgd
>    KVM: VMX: Define Hyper-V paravirt TLB flush fields iff Hyper-V is
>      enabled
>    KVM: VMX: Skip additional Hyper-V TLB EPTP flushes if one fails
>    KVM: VMX: Track root HPA instead of EPTP for paravirt Hyper-V TLB
>      flush
> 
>   arch/x86/include/asm/kvm_host.h |   4 +-
>   arch/x86/kvm/mmu.h              |   2 +-
>   arch/x86/kvm/svm/svm.c          |   4 +-
>   arch/x86/kvm/vmx/vmx.c          | 134 ++++++++++++++++++--------------
>   arch/x86/kvm/vmx/vmx.h          |  19 ++---
>   5 files changed, 87 insertions(+), 76 deletions(-)
> 

Queued, thanks.

Paolo
Sean Christopherson March 2, 2021, 6:56 p.m. UTC | #2
On Wed, Jan 27, 2021, Paolo Bonzini wrote:
> On 27/10/20 22:23, Sean Christopherson wrote:
> > Clean up KVM's PV TLB flushing when running with EPT on Hyper-V, i.e. as
> > a nested VMM.  No real goal in mind other than the sole patch in v1, which
> > is a minor change to avoid a future mixup when TDX also wants to define
> > .remote_flush_tlb.  Everything else is opportunistic clean up.
> > 
> > Patch 1 legitimately tested on VMX (no SVM), everything else effectively
> > build tested only.
> > 
> > v3:
> >    - Add a patch to pass the root_hpa instead of pgd to vmx_load_mmu_pgd()
> >      and retrieve the active PCID only when necessary.  [Vitaly]
> >    - Selectively collects reviews (skipped a few due to changes). [Vitaly]
> >    - Explicitly invalidate hv_tlb_eptp instead of leaving it valid when
> >      the mismatch tracker "knows" it's invalid. [Vitaly]
> >    - Change the last patch to use "hv_root_ept" instead of "hv_tlb_pgd"
> >      to better reflect what is actually being tracked.
> > 
> > v2: Rewrite everything.
> > Sean Christopherson (11):
> >    KVM: x86: Get active PCID only when writing a CR3 value
> >    KVM: VMX: Track common EPTP for Hyper-V's paravirt TLB flush
> >    KVM: VMX: Stash kvm_vmx in a local variable for Hyper-V paravirt TLB
> >      flush
> >    KVM: VMX: Fold Hyper-V EPTP checking into it's only caller
> >    KVM: VMX: Do Hyper-V TLB flush iff vCPU's EPTP hasn't been flushed
> >    KVM: VMX: Invalidate hv_tlb_eptp to denote an EPTP mismatch
> >    KVM: VMX: Don't invalidate hv_tlb_eptp if the new EPTP matches
> >    KVM: VMX: Explicitly check for hv_remote_flush_tlb when loading pgd
> >    KVM: VMX: Define Hyper-V paravirt TLB flush fields iff Hyper-V is
> >      enabled
> >    KVM: VMX: Skip additional Hyper-V TLB EPTP flushes if one fails
> >    KVM: VMX: Track root HPA instead of EPTP for paravirt Hyper-V TLB
> >      flush
> > 
> >   arch/x86/include/asm/kvm_host.h |   4 +-
> >   arch/x86/kvm/mmu.h              |   2 +-
> >   arch/x86/kvm/svm/svm.c          |   4 +-
> >   arch/x86/kvm/vmx/vmx.c          | 134 ++++++++++++++++++--------------
> >   arch/x86/kvm/vmx/vmx.h          |  19 ++---
> >   5 files changed, 87 insertions(+), 76 deletions(-)
> > 
> 
> Queued, thanks.

Looks like this got shadow-banned, I'll send v4.