In case a task manages to complete but it took just long enough to also
trigger the timeout handler, the current code results in a refcount
imbalance on lima_pm_idle.
While this can be a rare occurrence, when it happens it may fill user
logs with stack traces such as:
[10136.669170] WARNING: CPU: 0 PID: 0 at
drivers/gpu/drm/lima/lima_devfreq.c:205 lima_devfreq_record_idle+0xa0/0xb0
...
[10136.669459] pc : lima_devfreq_record_idle+0xa0/0xb0
...
[10136.669628] Call trace:
[10136.669634] lima_devfreq_record_idle+0xa0/0xb0
[10136.669646] lima_sched_pipe_task_done+0x5c/0xb0
[10136.669656] lima_gp_irq_handler+0xa8/0x120
[10136.669666] __handle_irq_event_percpu+0x48/0x160
[10136.669679] handle_irq_event+0x4c/0xc0
The imbalance happens because lima_sched_pipe_task_done() already calls
lima_pm_idle for this case if there was no error.
Check the error flag in the timeout handler to ensure we can never run
into this case.
Signed-off-by: Erico Nunes <nunes.er...@gmail.com>
---
drivers/gpu/drm/lima/lima_sched.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/lima/lima_sched.c
b/drivers/gpu/drm/lima/lima_sched.c
index c3bf8cda8498..66317296d831 100644
--- a/drivers/gpu/drm/lima/lima_sched.c
+++ b/drivers/gpu/drm/lima/lima_sched.c
@@ -427,7 +427,8 @@ static enum drm_gpu_sched_stat
lima_sched_timedout_job(struct drm_sched_job *job
pipe->current_vm = NULL;
pipe->current_task = NULL;
- lima_pm_idle(ldev);
+ if (pipe->error)
+ lima_pm_idle(ldev);
drm_sched_resubmit_jobs(&pipe->base);
drm_sched_start(&pipe->base, true);
--
2.43.0
