From b406e5a65b62a5bcb9afcf5ade8ccb534e0e745e Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu, 30 Apr 2020 19:33:24 +0100
Subject: drm/i915/pmu: Keep a reference to module while active
Git-commit: 3b55cdeb8f1b71444da866fd2568b1a18ba7f9c3
Patch-mainline: v5.8-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
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 <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200430183324.23984-1-chris@chris-wilson.co.uk
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
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;
}
--
2.28.0