From 3b55cdeb8f1b71444da866fd2568b1a18ba7f9c3 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 30 Apr 2020 19:33:24 +0100 Subject: [PATCH] drm/i915/pmu: Keep a reference to module while active While a perf event is open, keep a reference to the module so we don't remove the driver internals mid-sampling. Testcase: igt/perf_pmu/module-unload Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Cc: stable@vger.kernel.org Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20200430183324.23984-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_pmu.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c index 83c6a8ccd2cb..e991a707bdb7 100644 --- a/drivers/gpu/drm/i915/i915_pmu.c +++ b/drivers/gpu/drm/i915/i915_pmu.c @@ -442,6 +442,7 @@ static u64 count_interrupts(struct drm_i915_private *i915) static void i915_pmu_event_destroy(struct perf_event *event) { WARN_ON(event->parent); + module_put(THIS_MODULE); } static int @@ -533,8 +534,10 @@ static int i915_pmu_event_init(struct perf_event *event) if (ret) return ret; - if (!event->parent) + if (!event->parent) { + __module_get(THIS_MODULE); event->destroy = i915_pmu_event_destroy; + } return 0; }