diff options
| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2022-01-12 18:01:34 +0100 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-01-28 13:38:26 +0100 |
| commit | 6cbbaab60ff33f59355492c241318046befd9ffc (patch) | |
| tree | b4c7e04bd25e93914e12090002c7ed3a9cd607d1 /virt | |
| parent | KVM: nVMX: Implement evmcs_field_offset() suitable for handle_vmread() (diff) | |
| download | linux-6cbbaab60ff33f59355492c241318046befd9ffc.tar.xz linux-6cbbaab60ff33f59355492c241318046befd9ffc.zip | |
KVM: nVMX: Allow VMREAD when Enlightened VMCS is in use
Hyper-V TLFS explicitly forbids VMREAD and VMWRITE instructions when
Enlightened VMCS interface is in use:
"Any VMREAD or VMWRITE instructions while an enlightened VMCS is
active is unsupported and can result in unexpected behavior.""
Windows 11 + WSL2 seems to ignore this, attempts to VMREAD VMCS field
0x4404 ("VM-exit interruption information") are observed. Failing
these attempts with nested_vmx_failInvalid() makes such guests
unbootable.
Microsoft confirms this is a Hyper-V bug and claims that it'll get fixed
eventually but for the time being we need a workaround. (Temporary) allow
VMREAD to get data from the currently loaded Enlightened VMCS.
Note: VMWRITE instructions remain forbidden, it is not clear how to
handle them properly and hopefully won't ever be needed.
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20220112170134.1904308-6-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'virt')
0 files changed, 0 insertions, 0 deletions