Re: [PATCH v8 4/4] kvm: vmx: virtualize split lock detection

From: Thomas Gleixner
Date: Wed Apr 15 2020 - 15:47:37 EST


Xiaoyao Li <xiaoyao.li@xxxxxxxxx> writes:

> Due to the fact that TEST_CTRL MSR is per-core scope, i.e., the sibling
> threads in the same physical CPU core share the same MSR, only
> advertising feature split lock detection to guest when SMT is disabled
> or unsupported, for simplicitly.

That's not for simplicity. It's for correctness because you cannot
provide consistent state to a guest.

Thanks,

tglx