Re: [PATCH v5 0/5] KVM: arm64: PMU: Fix SET_ONE_REG for vPMC regs

From: Oliver Upton
Date: Mon Mar 17 2025 - 16:01:32 EST


On Sat, 15 Mar 2025 18:12:09 +0900, Akihiko Odaki wrote:
> Prepare vPMC registers for user-initiated changes after first run. This
> is important specifically for debugging Windows on QEMU with GDB; QEMU
> tries to write back all visible registers when resuming the VM execution
> with GDB, corrupting the PMU state. Windows always uses the PMU so this
> can cause adverse effects on that particular OS.
>
> This series also contains patch "KVM: arm64: PMU: Set raw values from
> user to PM{C,I}NTEN{SET,CLR}, PMOVS{SET,CLR}", which reverts semantic
> changes made for the mentioned registers in the past. It is necessary
> to migrate the PMU state properly on Firecracker, QEMU, and crosvm.
>
> [...]

Squashed in a fix for CONFIG_HW_PERF_EVENTS=n build.

Applied to next, thanks!

[1/5] KVM: arm64: PMU: Set raw values from user to PM{C,I}NTEN{SET,CLR}, PMOVS{SET,CLR}
https://git.kernel.org/kvmarm/kvmarm/c/f2aeb7bbd574
[2/5] KVM: arm64: PMU: Assume PMU presence in pmu-emul.c
https://git.kernel.org/kvmarm/kvmarm/c/be5ccac3f15e
[3/5] KVM: arm64: PMU: Fix SET_ONE_REG for vPMC regs
https://git.kernel.org/kvmarm/kvmarm/c/64074ca8ca92
[4/5] KVM: arm64: PMU: Reload when user modifies registers
https://git.kernel.org/kvmarm/kvmarm/c/1db4aaa05589
[5/5] KVM: arm64: PMU: Reload when resetting
https://git.kernel.org/kvmarm/kvmarm/c/fe53538069bb

--
Best,
Oliver