From: Janusz Krzysztofik janusz.krzysztofik@intel.com

If there are active users of a device during driver unbind, the driver now panics on non-empty list of free cachelines.

By design, chachelines which are not in use are kept on a list of free chachelines associated with a timeline and rmoved from that list either when in use or when the timeline is destroyed. Timelines in turn are assigned to open file descriptors.

As long as a device file is open, its associated timeline with its list of free cachelines will be hopefully destroyed on device close, either while outstanding execlists are destroyed or on i915_timeline_put() called directly, so as long as device file descriptors are protected from unwanted user activities by the device being marked unplugged, there should be no reason to panic.

Moreover, timeline mutex which is destroyed right after the check for emptyness of a free cacheline list succeeds is never used to protect that list, only a list of active cachelines, so it can be freely destroyed even if the former is not empty.

Simply remove the GEM_BUG_ON(!list_empty(&gt->hwsp_free_list)); line from i915_timelines_fini().

Signed-off-by: Janusz Krzysztofik janusz.krzysztofik@intel.com --- drivers/gpu/drm/i915/i915_timeline.c | 1 - 1 file changed, 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c index b2202d2e58a2..1f23c2dcc0da 100644 --- a/drivers/gpu/drm/i915/i915_timeline.c +++ b/drivers/gpu/drm/i915/i915_timeline.c @@ -325,7 +325,6 @@ void i915_timelines_fini(struct drm_i915_private *i915) struct i915_gt_timelines *gt = &i915->gt.timelines;

GEM_BUG_ON(!list_empty(&gt->active_list)); - GEM_BUG_ON(!list_empty(&gt->hwsp_free_list));

mutex_destroy(&gt->mutex); }