drm/xe: cancel pending job timer before freeing scheduler

The async call to __guc_exec_queue_fini_async frees the scheduler
while a submission may time out and restart. To prevent this race
condition, the pending job timer should be canceled before freeing
the scheduler.

V3(MattB):
 - Adjust position of cancel pending job
 - Remove gitlab issue# from commit message
V2(MattB):
 - Cancel pending jobs before scheduler finish

Fixes: a20c75d ("drm/xe: Call __guc_exec_queue_fini_async direct for KERNEL exec_queues")
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250225045754.600905-1-tejas.upadhyay@intel.com
Signed-off-by: Tejas Upadhyay <tejas.upadhyay@intel.com>

Author: tejasup

drivers/gpu/drm/xe/xe_guc_submit.c

@@ -1248,6 +1248,8 @@ static void __guc_exec_queue_fini_async(struct work_struct *w)
 
 	if (xe_exec_queue_is_lr(q))
 		cancel_work_sync(&ge->lr_tdr);
+	/* Confirm no work left behind accessing device structures */
+	cancel_delayed_work_sync(&ge->sched.base.work_tdr);
 	release_guc_id(guc, q);
 	xe_sched_entity_fini(&ge->entity);
 	xe_sched_fini(&ge->sched);