Re: [PATCH kvm-unit-tests] x86/pmu: Check counter is working properly before AMD pmu init

From: Sean Christopherson
Date: Wed Jun 07 2023 - 17:49:01 EST


On Tue, Feb 21, 2023, Like Xu wrote:
> From: Like Xu <likexu@xxxxxxxxxxx>
>
> Avoid misleading pmu initialisation when vPMU is globally disabled
> by performing a read/write consistency test on one of AMD's counters.
> Without this check, pmu test will fail rather than be skipped.

This is unnecessary, the testcases can instead check KVM's enable_pmu module param.
Of course, runtime.bash has a bug and doesn't play nice with multiple requirements,
but that's easy enough to fix. Patches incoming.

@@ -206,7 +206,7 @@ extra_params = -cpu max,vendor=GenuineIntel
[pmu]
file = pmu.flat
extra_params = -cpu max
-check = /proc/sys/kernel/nmi_watchdog=0
+check = /sys/module/kvm/parameters/enable_pmu=Y /proc/sys/kernel/nmi_watchdog=0
accel = kvm
groups = pmu