KVM: nVMX: Do not flush TLB on L1<->L2 transitions if L1 uses VPID and EPT

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If L1 uses VPID, it expects TLB to not be flushed on L1<->L2
transitions. However, code currently flushes TLB nonetheless if we
didn't allocate a vpid02 for L2. As in this case,
vmcs02->vpid == vmcs01->vpid == vmx->vpid.

But, if L1 uses EPT, TLB entires populated by L2 are tagged with EPTP02
while TLB entries populated by L1 are tagged with EPTP01.
Therefore, we can also avoid TLB flush if L1 uses VPID and EPT.

Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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Liran Alon 2018-10-08 23:42:20 +03:00 • committed by Paolo Bonzini

parent 327c072187

commit efebf0aaec

1 changed files with 27 additions and 10 deletions

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arch/x86/kvm/vmx.c

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