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From: Mingwei Zhang <mizhang@google.com>
To: "Mi, Dapeng" <dapeng1.mi@linux.intel.com>
Cc: maobibo <maobibo@loongson.cn>,
	Sean Christopherson <seanjc@google.com>,
	 Xiong Zhang <xiong.y.zhang@linux.intel.com>,
	pbonzini@redhat.com, peterz@infradead.org,  kan.liang@intel.com,
	zhenyuw@linux.intel.com, jmattson@google.com,
	 kvm@vger.kernel.org, linux-perf-users@vger.kernel.org,
	 linux-kernel@vger.kernel.org, zhiyuan.lv@intel.com,
	eranian@google.com,  irogers@google.com, samantha.alt@intel.com,
	like.xu.linux@gmail.com,  chao.gao@intel.com
Subject: Re: [RFC PATCH 23/41] KVM: x86/pmu: Implement the save/restore of PMU state for Intel CPU
Date: Tue, 23 Apr 2024 00:10:35 -0700	[thread overview]
Message-ID: <CAL715W+BpyX3EeKr=3ipMH8W30wmhMkxg2Fx2OET9cvQ480cgg@mail.gmail.com> (raw)
In-Reply-To: <729c4b30-163c-4115-a380-14ece533a8b9@linux.intel.com>

On Mon, Apr 22, 2024 at 11:45 PM Mi, Dapeng <dapeng1.mi@linux.intel.com> wrote:
>
>
> On 4/23/2024 2:08 PM, maobibo wrote:
> >
> >
> > On 2024/4/23 下午12:23, Mingwei Zhang wrote:
> >> On Mon, Apr 22, 2024 at 8:55 PM maobibo <maobibo@loongson.cn> wrote:
> >>>
> >>>
> >>>
> >>> On 2024/4/23 上午11:13, Mi, Dapeng wrote:
> >>>>
> >>>> On 4/23/2024 10:53 AM, maobibo wrote:
> >>>>>
> >>>>>
> >>>>> On 2024/4/23 上午10:44, Mi, Dapeng wrote:
> >>>>>>
> >>>>>> On 4/23/2024 9:01 AM, maobibo wrote:
> >>>>>>>
> >>>>>>>
> >>>>>>> On 2024/4/23 上午1:01, Sean Christopherson wrote:
> >>>>>>>> On Mon, Apr 22, 2024, maobibo wrote:
> >>>>>>>>> On 2024/4/16 上午6:45, Sean Christopherson wrote:
> >>>>>>>>>> On Mon, Apr 15, 2024, Mingwei Zhang wrote:
> >>>>>>>>>>> On Mon, Apr 15, 2024 at 10:38 AM Sean Christopherson
> >>>>>>>>>>> <seanjc@google.com> wrote:
> >>>>>>>>>>>> One my biggest complaints with the current vPMU code is that
> >>>>>>>>>>>> the roles and
> >>>>>>>>>>>> responsibilities between KVM and perf are poorly defined,
> >>>>>>>>>>>> which
> >>>>>>>>>>>> leads to suboptimal
> >>>>>>>>>>>> and hard to maintain code.
> >>>>>>>>>>>>
> >>>>>>>>>>>> Case in point, I'm pretty sure leaving guest values in PMCs
> >>>>>>>>>>>> _would_ leak guest
> >>>>>>>>>>>> state to userspace processes that have RDPMC permissions, as
> >>>>>>>>>>>> the PMCs might not
> >>>>>>>>>>>> be dirty from perf's perspective (see
> >>>>>>>>>>>> perf_clear_dirty_counters()).
> >>>>>>>>>>>>
> >>>>>>>>>>>> Blindly clearing PMCs in KVM "solves" that problem, but in
> >>>>>>>>>>>> doing so makes the
> >>>>>>>>>>>> overall code brittle because it's not clear whether KVM
> >>>>>>>>>>>> _needs_
> >>>>>>>>>>>> to clear PMCs,
> >>>>>>>>>>>> or if KVM is just being paranoid.
> >>>>>>>>>>>
> >>>>>>>>>>> So once this rolls out, perf and vPMU are clients directly to
> >>>>>>>>>>> PMU HW.
> >>>>>>>>>>
> >>>>>>>>>> I don't think this is a statement we want to make, as it opens a
> >>>>>>>>>> discussion
> >>>>>>>>>> that we won't win.  Nor do I think it's one we *need* to make.
> >>>>>>>>>> KVM doesn't need
> >>>>>>>>>> to be on equal footing with perf in terms of owning/managing PMU
> >>>>>>>>>> hardware, KVM
> >>>>>>>>>> just needs a few APIs to allow faithfully and accurately
> >>>>>>>>>> virtualizing a guest PMU.
> >>>>>>>>>>
> >>>>>>>>>>> Faithful cleaning (blind cleaning) has to be the baseline
> >>>>>>>>>>> implementation, until both clients agree to a "deal" between
> >>>>>>>>>>> them.
> >>>>>>>>>>> Currently, there is no such deal, but I believe we could have
> >>>>>>>>>>> one via
> >>>>>>>>>>> future discussion.
> >>>>>>>>>>
> >>>>>>>>>> What I am saying is that there needs to be a "deal" in place
> >>>>>>>>>> before this code
> >>>>>>>>>> is merged.  It doesn't need to be anything fancy, e.g. perf can
> >>>>>>>>>> still pave over
> >>>>>>>>>> PMCs it doesn't immediately load, as opposed to using
> >>>>>>>>>> cpu_hw_events.dirty to lazily
> >>>>>>>>>> do the clearing.  But perf and KVM need to work together from
> >>>>>>>>>> the
> >>>>>>>>>> get go, ie. I
> >>>>>>>>>> don't want KVM doing something without regard to what perf does,
> >>>>>>>>>> and vice versa.
> >>>>>>>>>>
> >>>>>>>>> There is similar issue on LoongArch vPMU where vm can directly
> >>>>>>>>> pmu
> >>>>>>>>> hardware
> >>>>>>>>> and pmu hw is shard with guest and host. Besides context switch
> >>>>>>>>> there are
> >>>>>>>>> other places where perf core will access pmu hw, such as tick
> >>>>>>>>> timer/hrtimer/ipi function call, and KVM can only intercept
> >>>>>>>>> context switch.
> >>>>>>>>
> >>>>>>>> Two questions:
> >>>>>>>>
> >>>>>>>>    1) Can KVM prevent the guest from accessing the PMU?
> >>>>>>>>
> >>>>>>>>    2) If so, KVM can grant partial access to the PMU, or is it all
> >>>>>>>> or nothing?
> >>>>>>>>
> >>>>>>>> If the answer to both questions is "yes", then it sounds like
> >>>>>>>> LoongArch *requires*
> >>>>>>>> mediated/passthrough support in order to virtualize its PMU.
> >>>>>>>
> >>>>>>> Hi Sean,
> >>>>>>>
> >>>>>>> Thank for your quick response.
> >>>>>>>
> >>>>>>> yes, kvm can prevent guest from accessing the PMU and grant partial
> >>>>>>> or all to access to the PMU. Only that if one pmu event is granted
> >>>>>>> to VM, host can not access this pmu event again. There must be pmu
> >>>>>>> event switch if host want to.
> >>>>>>
> >>>>>> PMU event is a software entity which won't be shared. did you
> >>>>>> mean if
> >>>>>> a PMU HW counter is granted to VM, then Host can't access the PMU HW
> >>>>>> counter, right?
> >>>>> yes, if PMU HW counter/control is granted to VM. The value comes from
> >>>>> guest, and is not meaningful for host.  Host pmu core does not know
> >>>>> that it is granted to VM, host still think that it owns pmu.
> >>>>
> >>>> That's one issue this patchset tries to solve. Current new mediated
> >>>> x86
> >>>> vPMU framework doesn't allow Host or Guest own the PMU HW resource
> >>>> simultaneously. Only when there is no !exclude_guest event on host,
> >>>> guest is allowed to exclusively own the PMU HW resource.
> >>>>
> >>>>
> >>>>>
> >>>>> Just like FPU register, it is shared by VM and host during different
> >>>>> time and it is lately switched. But if IPI or timer interrupt uses
> >>>>> FPU
> >>>>> register on host, there will be the same issue.
> >>>>
> >>>> I didn't fully get your point. When IPI or timer interrupt reach, a
> >>>> VM-exit is triggered to make CPU traps into host first and then the
> >>>> host
> >>> yes, it is.
> >>
> >> This is correct. And this is one of the points that we had debated
> >> internally whether we should do PMU context switch at vcpu loop
> >> boundary or VM Enter/exit boundary. (host-level) timer interrupt can
> >> force VM Exit, which I think happens every 4ms or 1ms, depending on
> >> configuration.
> >>
> >> One of the key reasons we currently propose this is because it is the
> >> same boundary as the legacy PMU, i.e., it would be simple to propose
> >> from the perf subsystem perspective.
> >>
> >> Performance wise, doing PMU context switch at vcpu boundary would be
> >> way better in general. But the downside is that perf sub-system lose
> >> the capability to profile majority of the KVM code (functions) when
> >> guest PMU is enabled.
> >>
> >>>
> >>>> interrupt handler is called. Or are you complaining the executing
> >>>> sequence of switching guest PMU MSRs and these interrupt handler?
> >>> In our vPMU implementation, it is ok if vPMU is switched in vm exit
> >>> path, however there is problem if vPMU is switched during vcpu thread
> >>> sched-out/sched-in path since IPI/timer irq interrupt access pmu
> >>> register in host mode.
> >>
> >> Oh, the IPI/timer irq handler will access PMU registers? I thought
> >> only the host-level NMI handler will access the PMU MSRs since PMI is
> >> registered under NMI.
> >>
> >> In that case, you should disable  IRQ during vcpu context switch. For
> >> NMI, we prevent its handler from accessing the PMU registers. In
> >> particular, we use a per-cpu variable to guard that. So, the
> >> host-level PMI handler for perf sub-system will check the variable
> >> before proceeding.
> >
> > perf core will access pmu hw in tick timer/hrtimer/ipi function call,
> > such as function perf_event_task_tick() is called in tick timer, there
> > are  event_function_call(event, __perf_event_xxx, &value) in file
> > kernel/events/core.c.
> >
> > https://lore.kernel.org/lkml/20240417065236.500011-1-gaosong@loongson.cn/T/#m15aeb79fdc9ce72dd5b374edd6acdcf7a9dafcf4
> >
>
> Just go through functions (not sure if all),  whether
> perf_event_task_tick() or the callbacks of event_function_call() would
> check the event->state first, if the event is in
> PERF_EVENT_STATE_INACTIVE, the PMU HW MSRs would not be touched really.
> In this new proposal, all host events with exclude_guest attribute would
> be put on PERF_EVENT_STATE_INACTIVE sate if guest own the PMU HW
> resource. So I think it's fine.
>

Is there any event in the host still having PERF_EVENT_STATE_ACTIVE?
If so, hmm, it will reach perf_pmu_disable(event->pmu), which will
access the global ctrl MSR.

  reply	other threads:[~2024-04-23  7:11 UTC|newest]

Thread overview: 181+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-26  8:54 [RFC PATCH 00/41] KVM: x86/pmu: Introduce passthrough vPM Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 01/41] perf: x86/intel: Support PERF_PMU_CAP_VPMU_PASSTHROUGH Xiong Zhang
2024-04-11 17:04   ` Sean Christopherson
2024-04-11 17:21     ` Liang, Kan
2024-04-11 17:24       ` Jim Mattson
2024-04-11 17:46         ` Sean Christopherson
2024-04-11 19:13           ` Liang, Kan
2024-04-11 20:43             ` Sean Christopherson
2024-04-11 21:04               ` Liang, Kan
2024-04-11 19:32           ` Sean Christopherson
2024-01-26  8:54 ` [RFC PATCH 02/41] perf: Support guest enter/exit interfaces Xiong Zhang
2024-03-20 16:40   ` Raghavendra Rao Ananta
2024-03-20 17:12     ` Liang, Kan
2024-04-11 18:06   ` Sean Christopherson
2024-04-11 19:53     ` Liang, Kan
2024-04-12 19:17       ` Sean Christopherson
2024-04-12 20:56         ` Liang, Kan
2024-04-15 16:03           ` Liang, Kan
2024-04-16  5:34             ` Zhang, Xiong Y
2024-04-16 12:48               ` Liang, Kan
2024-04-17  9:42                 ` Zhang, Xiong Y
2024-04-18 16:11                   ` Sean Christopherson
2024-04-19  1:37                     ` Zhang, Xiong Y
2024-04-26  4:09       ` Zhang, Xiong Y
2024-01-26  8:54 ` [RFC PATCH 03/41] perf: Set exclude_guest onto nmi_watchdog Xiong Zhang
2024-04-11 18:56   ` Sean Christopherson
2024-01-26  8:54 ` [RFC PATCH 04/41] perf: core/x86: Add support to register a new vector for PMI handling Xiong Zhang
2024-04-11 17:10   ` Sean Christopherson
2024-04-11 19:05     ` Sean Christopherson
2024-04-12  3:56     ` Zhang, Xiong Y
2024-04-13  1:17       ` Mi, Dapeng
2024-01-26  8:54 ` [RFC PATCH 05/41] KVM: x86/pmu: Register PMI handler for passthrough PMU Xiong Zhang
2024-04-11 19:07   ` Sean Christopherson
2024-04-12  5:44     ` Zhang, Xiong Y
2024-01-26  8:54 ` [RFC PATCH 06/41] perf: x86: Add function to switch PMI handler Xiong Zhang
2024-04-11 19:17   ` Sean Christopherson
2024-04-11 19:34     ` Sean Christopherson
2024-04-12  6:03       ` Zhang, Xiong Y
2024-04-12  5:57     ` Zhang, Xiong Y
2024-01-26  8:54 ` [RFC PATCH 07/41] perf/x86: Add interface to reflect virtual LVTPC_MASK bit onto HW Xiong Zhang
2024-04-11 19:21   ` Sean Christopherson
2024-04-12  6:17     ` Zhang, Xiong Y
2024-01-26  8:54 ` [RFC PATCH 08/41] KVM: x86/pmu: Add get virtual LVTPC_MASK bit function Xiong Zhang
2024-04-11 19:22   ` Sean Christopherson
2024-01-26  8:54 ` [RFC PATCH 09/41] perf: core/x86: Forbid PMI handler when guest own PMU Xiong Zhang
2024-04-11 19:26   ` Sean Christopherson
2024-01-26  8:54 ` [RFC PATCH 10/41] perf: core/x86: Plumb passthrough PMU capability from x86_pmu to x86_pmu_cap Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 11/41] KVM: x86/pmu: Introduce enable_passthrough_pmu module parameter and propage to KVM instance Xiong Zhang
2024-04-11 20:54   ` Sean Christopherson
2024-04-11 21:03   ` Sean Christopherson
2024-01-26  8:54 ` [RFC PATCH 12/41] KVM: x86/pmu: Plumb through passthrough PMU to vcpu for Intel CPUs Xiong Zhang
2024-04-11 20:57   ` Sean Christopherson
2024-01-26  8:54 ` [RFC PATCH 13/41] KVM: x86/pmu: Add a helper to check if passthrough PMU is enabled Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 14/41] KVM: x86/pmu: Allow RDPMC pass through Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 15/41] KVM: x86/pmu: Manage MSR interception for IA32_PERF_GLOBAL_CTRL Xiong Zhang
2024-04-11 21:21   ` Sean Christopherson
2024-04-11 22:30     ` Jim Mattson
2024-04-11 23:27       ` Sean Christopherson
2024-04-13  2:10       ` Mi, Dapeng
2024-01-26  8:54 ` [RFC PATCH 16/41] KVM: x86/pmu: Create a function prototype to disable MSR interception Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 17/41] KVM: x86/pmu: Implement pmu function for Intel CPU " Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 18/41] KVM: x86/pmu: Intercept full-width GP counter MSRs by checking with perf capabilities Xiong Zhang
2024-04-11 21:23   ` Sean Christopherson
2024-04-11 21:50     ` Jim Mattson
2024-04-12 16:01       ` Sean Christopherson
2024-01-26  8:54 ` [RFC PATCH 19/41] KVM: x86/pmu: Whitelist PMU MSRs for passthrough PMU Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 20/41] KVM: x86/pmu: Introduce PMU operation prototypes for save/restore PMU context Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 21/41] KVM: x86/pmu: Introduce function prototype for Intel CPU to " Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 22/41] x86: Introduce MSR_CORE_PERF_GLOBAL_STATUS_SET for passthrough PMU Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 23/41] KVM: x86/pmu: Implement the save/restore of PMU state for Intel CPU Xiong Zhang
2024-04-11 21:26   ` Sean Christopherson
2024-04-13  2:29     ` Mi, Dapeng
2024-04-11 21:44   ` Sean Christopherson
2024-04-11 22:19     ` Jim Mattson
2024-04-11 23:31       ` Sean Christopherson
2024-04-13  3:19         ` Mi, Dapeng
2024-04-13  3:03     ` Mi, Dapeng
2024-04-13  3:34       ` Mingwei Zhang
2024-04-13  4:25         ` Mi, Dapeng
2024-04-15  6:06           ` Mingwei Zhang
2024-04-15 10:04             ` Mi, Dapeng
2024-04-15 16:44               ` Mingwei Zhang
2024-04-15 17:38                 ` Sean Christopherson
2024-04-15 17:54                   ` Mingwei Zhang
2024-04-15 22:45                     ` Sean Christopherson
2024-04-22  2:14                       ` maobibo
2024-04-22 17:01                         ` Sean Christopherson
2024-04-23  1:01                           ` maobibo
2024-04-23  2:44                             ` Mi, Dapeng
2024-04-23  2:53                               ` maobibo
2024-04-23  3:13                                 ` Mi, Dapeng
2024-04-23  3:26                                   ` maobibo
2024-04-23  3:59                                     ` Mi, Dapeng
2024-04-23  3:55                                   ` maobibo
2024-04-23  4:23                                     ` Mingwei Zhang
2024-04-23  6:08                                       ` maobibo
2024-04-23  6:45                                         ` Mi, Dapeng
2024-04-23  7:10                                           ` Mingwei Zhang [this message]
2024-04-23  8:24                                             ` Mi, Dapeng
2024-04-23  8:51                                               ` maobibo
2024-04-23 16:50                                               ` Mingwei Zhang
2024-04-23 12:12                                       ` maobibo
2024-04-23 17:02                                         ` Mingwei Zhang
2024-04-24  1:07                                           ` maobibo
2024-04-24  8:18                                           ` Mi, Dapeng
2024-04-24 15:00                                             ` Sean Christopherson
2024-04-25  3:55                                               ` Mi, Dapeng
2024-04-25  4:24                                                 ` Mingwei Zhang
2024-04-25 16:13                                                   ` Liang, Kan
2024-04-25 20:16                                                     ` Mingwei Zhang
2024-04-25 20:43                                                       ` Liang, Kan
2024-04-25 21:46                                                         ` Sean Christopherson
2024-04-26  1:46                                                           ` Mi, Dapeng
2024-04-26  3:12                                                             ` Mingwei Zhang
2024-04-26  4:02                                                               ` Mi, Dapeng
2024-04-26  4:46                                                                 ` Mingwei Zhang
2024-04-26 14:09                                                               ` Liang, Kan
2024-04-26 18:41                                                                 ` Mingwei Zhang
2024-04-26 19:06                                                                   ` Liang, Kan
2024-04-26 19:46                                                                     ` Sean Christopherson
2024-04-27  3:04                                                                       ` Mingwei Zhang
2024-04-28  0:58                                                                         ` Mi, Dapeng
2024-04-28  6:01                                                                           ` Mingwei Zhang
2024-04-29 17:44                                                                             ` Sean Christopherson
2024-05-01 17:43                                                                               ` Mingwei Zhang
2024-05-01 18:00                                                                                 ` Liang, Kan
2024-05-01 20:36                                                                                 ` Sean Christopherson
2024-04-29 13:08                                                                         ` Liang, Kan
2024-04-26 13:53                                                           ` Liang, Kan
2024-04-26  1:50                                                         ` Mi, Dapeng
2024-04-18 21:21                   ` Mingwei Zhang
2024-04-18 21:41                     ` Mingwei Zhang
2024-04-19  1:02                     ` Mi, Dapeng
2024-01-26  8:54 ` [RFC PATCH 24/41] KVM: x86/pmu: Zero out unexposed Counters/Selectors to avoid information leakage Xiong Zhang
2024-04-11 21:36   ` Sean Christopherson
2024-04-11 21:56     ` Jim Mattson
2024-01-26  8:54 ` [RFC PATCH 25/41] KVM: x86/pmu: Introduce macro PMU_CAP_PERF_METRICS Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 26/41] KVM: x86/pmu: Add host_perf_cap field in kvm_caps to record host PMU capability Xiong Zhang
2024-04-11 21:49   ` Sean Christopherson
2024-01-26  8:54 ` [RFC PATCH 27/41] KVM: x86/pmu: Clear PERF_METRICS MSR for guest Xiong Zhang
2024-04-11 21:50   ` Sean Christopherson
2024-04-13  3:29     ` Mi, Dapeng
2024-01-26  8:54 ` [RFC PATCH 28/41] KVM: x86/pmu: Switch IA32_PERF_GLOBAL_CTRL at VM boundary Xiong Zhang
2024-04-11 21:54   ` Sean Christopherson
2024-04-11 22:10     ` Jim Mattson
2024-04-11 22:54       ` Sean Christopherson
2024-04-11 23:08         ` Jim Mattson
2024-01-26  8:54 ` [RFC PATCH 29/41] KVM: x86/pmu: Exclude existing vLBR logic from the passthrough PMU Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 30/41] KVM: x86/pmu: Switch PMI handler at KVM context switch boundary Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 31/41] KVM: x86/pmu: Call perf_guest_enter() at PMU context switch Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 32/41] KVM: x86/pmu: Add support for PMU context switch at VM-exit/enter Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 33/41] KVM: x86/pmu: Make check_pmu_event_filter() an exported function Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 34/41] KVM: x86/pmu: Intercept EVENT_SELECT MSR Xiong Zhang
2024-04-11 21:55   ` Sean Christopherson
2024-01-26  8:54 ` [RFC PATCH 35/41] KVM: x86/pmu: Allow writing to event selector for GP counters if event is allowed Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 36/41] KVM: x86/pmu: Intercept FIXED_CTR_CTRL MSR Xiong Zhang
2024-04-11 21:56   ` Sean Christopherson
2024-01-26  8:54 ` [RFC PATCH 37/41] KVM: x86/pmu: Allow writing to fixed counter selector if counter is exposed Xiong Zhang
2024-04-11 22:03   ` Sean Christopherson
2024-04-13  4:12     ` Mi, Dapeng
2024-01-26  8:54 ` [RFC PATCH 38/41] KVM: x86/pmu: Introduce PMU helper to increment counter Xiong Zhang
2024-01-26  8:54 ` [RFC PATCH 39/41] KVM: x86/pmu: Implement emulated counter increment for passthrough PMU Xiong Zhang
2024-04-11 23:12   ` Sean Christopherson
2024-04-11 23:17     ` Sean Christopherson
2024-01-26  8:54 ` [RFC PATCH 40/41] KVM: x86/pmu: Separate passthrough PMU logic in set/get_msr() from non-passthrough vPMU Xiong Zhang
2024-04-11 23:18   ` Sean Christopherson
2024-04-18 21:54     ` Mingwei Zhang
2024-01-26  8:54 ` [RFC PATCH 41/41] KVM: nVMX: Add nested virtualization support for passthrough PMU Xiong Zhang
2024-04-11 23:21   ` Sean Christopherson
2024-04-11 17:03 ` [RFC PATCH 00/41] KVM: x86/pmu: Introduce passthrough vPM Sean Christopherson
2024-04-12  2:19   ` Zhang, Xiong Y
2024-04-12 18:32     ` Sean Christopherson
2024-04-15  1:06       ` Zhang, Xiong Y
2024-04-15 15:05         ` Sean Christopherson
2024-04-16  5:11           ` Zhang, Xiong Y
2024-04-18 20:46   ` Mingwei Zhang
2024-04-18 21:52     ` Mingwei Zhang
2024-04-19 19:14     ` Sean Christopherson
2024-04-19 22:02       ` Mingwei Zhang
2024-04-11 23:25 ` Sean Christopherson
2024-04-11 23:56   ` Mingwei Zhang

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