On Mon, Aug 28, 2023, Tianyi Liu wrote: > Hi, Sean: > > I have found that in the latest version of the kernel, some PMU events are > being lost. I used bisect and found out the breaking commit [1], which > moved the handling of NMI events from `handle_exception_irqoff` to > `vmx_vcpu_enter_exit`. > > If I revert this part as done in this patch, it works correctly. However, > I'm not really familiar with KVM, and I'm not sure about the intent behind > the original patch [1]. FWIW, the goal was to invoke vmx_do_nmi_irqoff() before leaving the "noinstr" region. I messed up and forgot that vmx_get_intr_info() relied on metadata being reset after VM-Exit :-/ > Could you please take a look on this? Thanks a lot. Please try this patch, it should fix the problem but I haven't fully tested it against an affected workload yet. I'll do that later today. https://lore.kernel.org/all/20230825014532.2846714-1-seanjc@xxxxxxxxxx
