KVM: SVM: Inject #UD on RDTSCP when it should be disabled in the guest

Intercept RDTSCP to inject #UD if RDTSC is disabled in the guest.

Note, SVM does not support intercepting RDPID.  Unlike VMX's
ENABLE_RDTSCP control, RDTSCP interception does not apply to RDPID.  This
is a benign virtualization hole as the host kernel (incorrectly) sets
MSR_TSC_AUX if RDTSCP is supported, and KVM loads the guest's MSR_TSC_AUX
into hardware if RDTSCP is supported in the host, i.e. KVM will not leak
the host's MSR_TSC_AUX to the guest.

But, when the kernel bug is fixed, KVM will start leaking the host's
MSR_TSC_AUX if RDPID is supported in hardware, but RDTSCP isn't available
for whatever reason.  This leak will be remedied in a future commit.

Fixes: 46896c73c1a4 ("KVM: svm: add support for RDTSCP")
Cc: [email protected]
Signed-off-by: Sean Christopherson <[email protected]>
Message-Id: <[email protected]>
Reviewed-by: Jim Mattson <[email protected]>
Reviewed-by: Reiji Watanabe <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>

0 files changed, 0 insertions, 0 deletions