Messages in this thread | | | Date | Tue, 14 Jun 2022 21:58:26 +0000 | Subject | [PATCH 0/5] KVM: nVMX: Support loading MSRs before nested state | From | Sean Christopherson <> |
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Fix two edge cases in nested VM-Enter where KVM loads garbage into BNDCFGS and/or DEBUGCTL when migrating a vCPU with L2 active. If userspace restores MSRs before nested state, userspace expects KVM to propagate L2's values to vmcs02. KVM already mostly handles this scenario, so even though I personally think it's rather ridiculous, it's easy for KVM to support, and given that our VMM does KVM_SET_MSRS before KVM_SET_NESTED_STATE...
Patches 4 and 5 are minor optimizations to handle BNDCFGS more like DEBUGCTL and/or the PKS MSR.
Sean Christopherson (5): KVM: nVMX: Snapshot pre-VM-Enter BNDCFGS for !nested_run_pending case KVM: nVMX: Snapshot pre-VM-Enter DEBUGCTL for !nested_run_pending case KVM: nVMX: Rename nested.vmcs01_* fields to nested.pre_vmenter_* KVM: nVMX: Save BNDCFGS to vmcs12 iff relevant controls are exposed to L1 KVM: nVMX: Update vmcs12 on BNDCFGS write, not at vmcs02=>vmcs12 sync
arch/x86/kvm/vmx/nested.c | 16 ++++++++-------- arch/x86/kvm/vmx/vmx.c | 13 +++++++++++++ arch/x86/kvm/vmx/vmx.h | 15 ++++++++++++--- 3 files changed, 33 insertions(+), 11 deletions(-)
base-commit: 8baacf67c76c560fed954ac972b63e6e59a6fba0 -- 2.36.1.476.g0c4daa206d-goog
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