diff options
author | Sean Christopherson <sean.j.christopherson@intel.com> | 2019-09-27 14:45:16 -0700 |
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committer | Paolo Bonzini <pbonzini@redhat.com> | 2019-10-22 13:34:07 +0200 |
commit | 04f11ef45810da5ae2542dd78cc353f3761bd2cb (patch) | |
tree | 00877eeaf65a19f4dd5c917da8009b4d768a4627 /drivers/crypto/ccp | |
parent | 83af5e65a89547633bab7278564219ca8e68b968 (diff) |
KVM: nVMX: Always write vmcs02.GUEST_CR3 during nested VM-Enter
Write the desired L2 CR3 into vmcs02.GUEST_CR3 during nested VM-Enter
instead of deferring the VMWRITE until vmx_set_cr3(). If the VMWRITE
is deferred, then KVM can consume a stale vmcs02.GUEST_CR3 when it
refreshes vmcs12->guest_cr3 during nested_vmx_vmexit() if the emulated
VM-Exit occurs without actually entering L2, e.g. if the nested run
is squashed because nested VM-Enter (from L1) is putting L2 into HLT.
Note, the above scenario can occur regardless of whether L1 is
intercepting HLT, e.g. L1 can intercept HLT and then re-enter L2 with
vmcs.GUEST_ACTIVITY_STATE=HALTED. But practically speaking, a VMM will
likely put a guest into HALTED if and only if it's not intercepting HLT.
In an ideal world where EPT *requires* unrestricted guest (and vice
versa), VMX could handle CR3 similar to how it handles RSP and RIP,
e.g. mark CR3 dirty and conditionally load it at vmx_vcpu_run(). But
the unrestricted guest silliness complicates the dirty tracking logic
to the point that explicitly handling vmcs02.GUEST_CR3 during nested
VM-Enter is a simpler overall implementation.
Cc: stable@vger.kernel.org
Reported-and-tested-by: Reto Buerki <reet@codelabs.ch>
Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'drivers/crypto/ccp')
0 files changed, 0 insertions, 0 deletions