When the driver unbinds, pmu is unregistered and i915->uabi_engines is set to RB_ROOT. Due to this, when i915 PMU tries to stop the engine events, it issues a warn_on because engine lookup fails.
All perf hooks are taking care of this using a pmu->closed flag that is set when PMU unregisters. The stop event seems to have been left out.
Check for pmu->closed in pmu_event_stop as well.
Based on discussion here - https://patchwork.freedesktop.org/patch/492079/?series=105790&rev=2
v2: s/is/if/ in commit title v3: Add fixes tag and cc stable
Cc: stable@vger.kernel.org # v5.11+ Fixes: b00bccb3f0bb ("drm/i915/pmu: Handle PCI unbind") Signed-off-by: Umesh Nerlige Ramappa umesh.nerlige.ramappa@intel.com Reviewed-by: Tvrtko Ursulin tvrtko.ursulin@intel.com --- drivers/gpu/drm/i915/i915_pmu.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c index 108b675088ba..f861863eb7c1 100644 --- a/drivers/gpu/drm/i915/i915_pmu.c +++ b/drivers/gpu/drm/i915/i915_pmu.c @@ -831,9 +831,18 @@ static void i915_pmu_event_start(struct perf_event *event, int flags)
static void i915_pmu_event_stop(struct perf_event *event, int flags) { + struct drm_i915_private *i915 = + container_of(event->pmu, typeof(*i915), pmu.base); + struct i915_pmu *pmu = &i915->pmu; + + if (pmu->closed) + goto out; + if (flags & PERF_EF_UPDATE) i915_pmu_event_read(event); i915_pmu_disable(event); + +out: event->hw.state = PERF_HES_STOPPED; }