Messages in this thread | | | Subject | Re: [PATCH v9 09/12] KVM: x86: Introduce a function to initialize the PT configuration | From | Paolo Bonzini <> | Date | Mon, 11 Jun 2018 13:41:53 +0200 |
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On 08/06/2018 16:56, Kang, Luwei wrote: >>> + /* Initialize and clear the no dependency bits */ >>> + vmx->pt_desc.ctl_bitmask = ~0ULL; >> This looks redundant, doesn't it? > This is a bit mask for RTIT_CTL MSR and it will make & with the value of RTIT_CLT from guest. > The reserved bits will be 1 in this bit mask and the setable bits are 0. > >>> + vmx->pt_desc.ctl_bitmask = ~(RTIT_CTL_TRACEEN | RTIT_CTL_OS | >>> + RTIT_CTL_USR | RTIT_CTL_TSC_EN | >> RTIT_CTL_DISRETC);
But it's set twice, so the first assignment is superfluous.
Paolo
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