On Mon, Nov 18, 2019 at 07:17:47PM +0100, Paolo Bonzini wrote: > If X86_FEATURE_RTM is disabled, the guest should not be able to access > MSR_IA32_TSX_CTRL. We can therefore use it in KVM to force all > transactions from the guest to abort. > > Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> So, without this patch guest OSes will incorrectly report "Not affected" at /sys/devices/system/cpu/vulnerabilities/tsx_async_abort if RTM is disabled in the VM configuration. Is there anything host userspace can do to detect this situation and issue a warning on that case? Is there anything the guest kernel can do to detect this and not report a false negative at /sys/.../tsx_async_abort? -- Eduardo
