Re: [PATCH v6 00/44] KVM: x86: Add support for mediated vPMUs

Sean Christopherson
2026-01-16T15:33:27Z

On Fri, 05 Dec 2025 16:16:36 -0800, Sean Christopherson wrote:
> This series is based on 'https://github.com/kvm-x86/linux next', but except
> for one minor conflict in perf should apply on Linus' tree once the KVM 6.19
> pull request lands. I considered waiting until 6.19-rc1 to post this, but
> I've had this in a "ready" state for a few weeks and want to get it out there.
>
> My hope/plan is that the perf changes will go through the tip tree with a
> stable tag/branch, and the KVM changes will go the kvm-x86 tree.
>
> [...]

Applied the KVM patches to kvm-x86 pmu, thanks!

[14/44] KVM: Add a simplified wrapper for registering perf callbacks
https://github.com/kvm-x86/linux/commit/4b24910c0569
[15/44] KVM: Add a simplified wrapper for registering perf callbacks
[DROPPED - already merged (and then fixed)]
[16/44] KVM: x86/pmu: Start stubbing in mediated PMU support
https://github.com/kvm-x86/linux/commit/3e51822b2fdf
[17/44] KVM: x86/pmu: Implement Intel mediated PMU requirements and constraints
https://github.com/kvm-x86/linux/commit/bfee4f07d880
[18/44] KVM: x86/pmu: Implement AMD mediated PMU requirements
https://github.com/kvm-x86/linux/commit/9ba0bb4ae76a
[19/44] KVM: x86/pmu: Register PMI handler for mediated vPMU
https://github.com/kvm-x86/linux/commit/1c4ba7286afb
[20/44] KVM: x86/pmu: Disable RDPMC interception for compatible mediated vPMU
https://github.com/kvm-x86/linux/commit/80624272129e
[21/44] KVM: x86/pmu: Load/save GLOBAL_CTRL via entry/exit fields for mediated PMU
https://github.com/kvm-x86/linux/commit/d3ba32d1ff2a
[22/44] KVM: x86/pmu: Disable interception of select PMU MSRs for mediated vPMUs
https://github.com/kvm-x86/linux/commit/2904df6692f4
[23/44] KVM: x86/pmu: Bypass perf checks when emulating mediated PMU counter accesses
https://github.com/kvm-x86/linux/commit/0ea0d6314870
[24/44] KVM: x86/pmu: Introduce eventsel_hw to prepare for pmu event filtering
https://github.com/kvm-x86/linux/commit/02918f007792
[25/44] KVM: x86/pmu: Reprogram mediated PMU event selectors on event filter updates
https://github.com/kvm-x86/linux/commit/3db871fe185b
[26/44] KVM: x86/pmu: Always stuff GuestOnly=1,HostOnly=0 for mediated PMCs on AMD
https://github.com/kvm-x86/linux/commit/a2f4ba534cc5
[27/44] KVM: x86/pmu: Load/put mediated PMU context when entering/exiting guest
https://github.com/kvm-x86/linux/commit/56bb27369750
[28/44] KVM: x86/pmu: Disallow emulation in the fastpath if mediated PMCs are active
https://github.com/kvm-x86/linux/commit/f7a65e58d643
[29/44] KVM: x86/pmu: Handle emulated instruction for mediated vPMU
https://github.com/kvm-x86/linux/commit/283a5aa57b22
[30/44] KVM: nVMX: Add macros to simplify nested MSR interception setting
https://github.com/kvm-x86/linux/commit/cb58327c4c8a
[31/44] KVM: nVMX: Disable PMU MSR interception as appropriate while running L2
https://github.com/kvm-x86/linux/commit/88ebc2a3199c
[32/44] KVM: nSVM: Disable PMU MSR interception as appropriate while running L2
https://github.com/kvm-x86/linux/commit/3b36160d9406
[33/44] KVM: x86/pmu: Expose enable_mediated_pmu parameter to user space
https://github.com/kvm-x86/linux/commit/860bcb1021f5
[34/44] KVM: x86/pmu: Elide WRMSRs when loading guest PMCs if values already match
https://github.com/kvm-x86/linux/commit/b0b6a8d3be16
[35/44] KVM: VMX: Drop intermediate "guest" field from msr_autostore
https://github.com/kvm-x86/linux/commit/462f092dc55c
[36/44] KVM: nVMX: Don't update msr_autostore count when saving TSC for vmcs12
https://github.com/kvm-x86/linux/commit/58f21a01417f
[37/44] KVM: VMX: Dedup code for removing MSR from VMCS's auto-load list
https://github.com/kvm-x86/linux/commit/0bd29379114b
[38/44] KVM: VMX: Drop unused @entry_only param from add_atomic_switch_msr()
https://github.com/kvm-x86/linux/commit/84ac00042a28
[39/44] KVM: VMX: Bug the VM if either MSR auto-load list is full
https://github.com/kvm-x86/linux/commit/2ed57bb89976
[40/44] KVM: VMX: Set MSR index auto-load entry if and only if entry is "new"
https://github.com/kvm-x86/linux/commit/0c4ff0866fc1
[41/44] KVM: VMX: Compartmentalize adding MSRs to host vs. guest auto-load list
https://github.com/kvm-x86/linux/commit/2239d137a71d
[42/44] KVM: VMX: Dedup code for adding MSR to VMCS's auto list
https://github.com/kvm-x86/linux/commit/c3d6a7210a4d
[43/44] KVM: VMX: Initialize vmcs01.VM_EXIT_MSR_STORE_ADDR with list address
https://github.com/kvm-x86/linux/commit/9757a5aebcd6
[44/44] KVM: VMX: Add mediated PMU support for CPUs without "save perf global ctrl"
https://github.com/kvm-x86/linux/commit/d374b89edbb9

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