Paolo Bonzini <pbonzini@xxxxxxxxxx> writes: > On 03/02/20 16:16, Xiaoyao Li wrote: >> A sane guest should never tigger emulation on a split-lock access, but >> it cannot prevent malicous guest from doing this. So just emulating the >> access as a write if it's a split-lock access to avoid malicous guest >> polluting the kernel log. > > Saying that anything doing a split lock access is malicious makes little > sense. Correct, but we also have to accept, that split lock access can be used in a malicious way, aka. DoS. > Split lock detection is essentially a debugging feature, there's a > reason why the MSR is called "TEST_CTL". So you don't want to make the The fact that it ended up in MSR_TEST_CTL does not say anything. That's where they it ended up to be as it was hastily cobbled together for whatever reason. Thanks, tglx