6.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Karol Wachowski karol.wachowski@intel.com
commit ab680dc6c78aa035e944ecc8c48a1caab9f39924 upstream.
Fix deadlock in job submission and abort handling. When a thread aborts currently executing jobs due to a fault, it first locks the global lock protecting submitted_jobs (#1).
After the last job is destroyed, it proceeds to release the related context and locks file_priv (#2). Meanwhile, in the job submission thread, the file_priv lock (#2) is taken first, and then the submitted_jobs lock (#1) is obtained when a job is added to the submitted jobs list.
CPU0 CPU1 ---- ---- (for example due to a fault) (jobs submissions keep coming)
lock(&vdev->submitted_jobs_lock) #1 ivpu_jobs_abort_all() job_destroy() lock(&file_priv->lock) #2 lock(&vdev->submitted_jobs_lock) #1 file_priv_release() lock(&vdev->context_list_lock) lock(&file_priv->lock) #2
This order of locking causes a deadlock. To resolve this issue, change the order of locking in ivpu_job_submit().
Signed-off-by: Karol Wachowski karol.wachowski@intel.com Signed-off-by: Maciej Falkowski maciej.falkowski@linux.intel.com Reviewed-by: Jacek Lawrynowicz jacek.lawrynowicz@linux.intel.com Signed-off-by: Jacek Lawrynowicz jacek.lawrynowicz@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20250107173238.381120-12-macie... Signed-off-by: Jacek Lawrynowicz jacek.lawrynowicz@linux.intel.com [ This backport required small adjustments to ivpu_job_submit(), which lacks support for explicit command queue creation added in 6.15. ] Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/accel/ivpu/ivpu_job.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-)
--- a/drivers/accel/ivpu/ivpu_job.c +++ b/drivers/accel/ivpu/ivpu_job.c @@ -532,6 +532,7 @@ static int ivpu_job_submit(struct ivpu_j if (ret < 0) return ret;
+ mutex_lock(&vdev->submitted_jobs_lock); mutex_lock(&file_priv->lock);
cmdq = ivpu_cmdq_acquire(file_priv, priority); @@ -539,11 +540,9 @@ static int ivpu_job_submit(struct ivpu_j ivpu_warn_ratelimited(vdev, "Failed to get job queue, ctx %d engine %d prio %d\n", file_priv->ctx.id, job->engine_idx, priority); ret = -EINVAL; - goto err_unlock_file_priv; + goto err_unlock; }
- mutex_lock(&vdev->submitted_jobs_lock); - is_first_job = xa_empty(&vdev->submitted_jobs_xa); ret = xa_alloc_cyclic(&vdev->submitted_jobs_xa, &job->job_id, job, file_priv->job_limit, &file_priv->job_id_next, GFP_KERNEL); @@ -551,7 +550,7 @@ static int ivpu_job_submit(struct ivpu_j ivpu_dbg(vdev, JOB, "Too many active jobs in ctx %d\n", file_priv->ctx.id); ret = -EBUSY; - goto err_unlock_submitted_jobs; + goto err_unlock; }
ret = ivpu_cmdq_push_job(cmdq, job); @@ -574,22 +573,20 @@ static int ivpu_job_submit(struct ivpu_j job->job_id, file_priv->ctx.id, job->engine_idx, priority, job->cmd_buf_vpu_addr, cmdq->jobq->header.tail);
- mutex_unlock(&vdev->submitted_jobs_lock); mutex_unlock(&file_priv->lock);
if (unlikely(ivpu_test_mode & IVPU_TEST_MODE_NULL_HW)) { - mutex_lock(&vdev->submitted_jobs_lock); ivpu_job_signal_and_destroy(vdev, job->job_id, VPU_JSM_STATUS_SUCCESS); - mutex_unlock(&vdev->submitted_jobs_lock); }
+ mutex_unlock(&vdev->submitted_jobs_lock); + return 0;
err_erase_xa: xa_erase(&vdev->submitted_jobs_xa, job->job_id); -err_unlock_submitted_jobs: +err_unlock: mutex_unlock(&vdev->submitted_jobs_lock); -err_unlock_file_priv: mutex_unlock(&file_priv->lock); ivpu_rpm_put(vdev); return ret;