diff options
author | Marc Zyngier <maz@kernel.org> | 2025-02-17 10:24:43 +0000 |
---|---|---|
committer | Marc Zyngier <maz@kernel.org> | 2025-04-11 12:59:10 +0100 |
commit | 022435334393d56f4d6bc398cf16430067807b0a (patch) | |
tree | 5024fda3788909e90a8cd78596198f8a9130ae3b /tools/perf/scripts/python/gecko.py | |
parent | c8823e51b534d490ec27d372596eb35d2bb7193c (diff) |
KVM: arm64: Contextualise the handling of PMCR_EL0.P writes
Contrary to what the comment says in kvm_pmu_handle_pmcr(),
writing PMCR_EL0.P==1 has the following effects:
<quote>
The event counters affected by this field are:
* All event counters in the first range.
* If any of the following are true, all event counters in the second
range:
- EL2 is disabled or not implemented in the current Security state.
- The PE is executing at EL2 or EL3.
</quote>
where the "first range" represent the counters in the [0..HPMN-1]
range, and the "second range" the counters in the [HPMN..MAX] range.
It so appears that writing P from EL2 should nuke all counters,
and not just the "guest" view. Just do that, and nuke the misleading
comment.
Reported-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'tools/perf/scripts/python/gecko.py')
0 files changed, 0 insertions, 0 deletions