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Peter Anvin" , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, Yongwei Ma , Xiong Zhang , Jim Mattson , Zide Chen , Eranian Stephane , Shukla Manali , Nikunj Dadhania Content-Type: text/plain; charset="us-ascii" On Fri, Aug 01, 2025, Sean Christopherson wrote: > On Wed, Jul 30, 2025, Dapeng Mi wrote: > > > > On 7/30/2025 8:38 AM, Sean Christopherson wrote: > > > On Tue, Jul 29, 2025, Dapeng Mi wrote: > > >> BTW, Sean, may I know your plan about the mediated vPMU v5 patch set? Thanks. > > > I'll get it out this week (hopefully tomorrow). > > > > Thumbs up! Thanks. > > I lied, I'm not going to get it out until Monday. Figuring out how to deal with > instruction emulation in the fastpath VM-Exit handlers took me longer than I was > hoping/expecting. > > It's fully tested, and I have all but one changelog written, but I'm out of time > for today (I made a stupid goof (inverted a !) that cost me an ~hour today, *sigh*). > > Unless I get hit by a meteor, I'll get it out Monday. *sigh* Wrong again (fortunately, I didn't get hit by a meteor). Long story short, I revisited (yet again) how to deal with enabling the mediated PMU. I had been doing almost all of my testing with a hack to force-enable a mediated PMU, and when it came time to rip that out, I just couldn't convince myself that requiring userspace to enable KVM_CAP_PMU_CAPABILITY was the best behavior (I especially hated that PMU support would silently disappear). So, bad news is, v5 isn't happening today. Good news is that I think I figured out a not-awful solution for enabling the mediated PMU. I'll post details (and hopefully v5) tomorrow.