Re: [PATCH 2/3] accel/ivpu: Fix locking order in ivpu_job_submit

[Sasha Levin <sashal@kernel.org>]

[ Sasha's backport helper bot ]

Hi,

✅ All tests passed successfully. No issues detected.
No action required from the submitter.

The upstream commit SHA1 provided is correct: ab680dc6c78aa035e944ecc8c48a1caab9f39924

WARNING: Author mismatch between patch and upstream commit:
Backport author: Jacek Lawrynowicz<jacek.lawrynowicz@linux.intel.com>
Commit author: Karol Wachowski<karol.wachowski@intel.com>

Note: The patch differs from the upstream commit:
---
1:  ab680dc6c78aa ! 1:  b7d18d7cd5b08 accel/ivpu: Fix locking order in ivpu_job_submit
    @@ Metadata
      ## Commit message ##
         accel/ivpu: Fix locking order in ivpu_job_submit
     
    +    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).
    @@ Commit message
         This order of locking causes a deadlock. To resolve this issue,
         change the order of locking in ivpu_job_submit().
     
    +    Cc: <stable@vger.kernel.org> # v6.14
         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>
    @@ Commit message
         Link: https://patchwork.freedesktop.org/patch/msgid/20250107173238.381120-12-maciej.falkowski@linux.intel.com
     
      ## drivers/accel/ivpu/ivpu_job.c ##
    -@@ drivers/accel/ivpu/ivpu_job.c: static int ivpu_job_submit(struct ivpu_job *job, u8 priority, u32 cmdq_id)
    +@@ drivers/accel/ivpu/ivpu_job.c: static int ivpu_job_submit(struct ivpu_job *job, u8 priority)
      	if (ret < 0)
      		return ret;
      
     +	mutex_lock(&vdev->submitted_jobs_lock);
      	mutex_lock(&file_priv->lock);
      
    - 	if (cmdq_id == 0)
    -@@ drivers/accel/ivpu/ivpu_job.c: static int ivpu_job_submit(struct ivpu_job *job, u8 priority, u32 cmdq_id)
    - 	if (!cmdq) {
    - 		ivpu_warn_ratelimited(vdev, "Failed to get job queue, ctx %d\n", file_priv->ctx.id);
    + 	cmdq = ivpu_cmdq_acquire(file_priv, priority);
    +@@ drivers/accel/ivpu/ivpu_job.c: static int ivpu_job_submit(struct ivpu_job *job, u8 priority)
    + 		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;
      	}
      
    - 	ret = ivpu_cmdq_register(file_priv, cmdq);
    - 	if (ret) {
    - 		ivpu_err(vdev, "Failed to register command queue: %d\n", ret);
    --		goto err_unlock_file_priv;
    -+		goto err_unlock;
    - 	}
    - 
    - 	job->cmdq_id = cmdq->id;
    - 
     -	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);
    -@@ drivers/accel/ivpu/ivpu_job.c: static int ivpu_job_submit(struct ivpu_job *job, u8 priority, u32 cmdq_id)
    +@@ drivers/accel/ivpu/ivpu_job.c: static int ivpu_job_submit(struct ivpu_job *job, u8 priority)
      		ivpu_dbg(vdev, JOB, "Too many active jobs in ctx %d\n",
      			 file_priv->ctx.id);
      		ret = -EBUSY;
    @@ drivers/accel/ivpu/ivpu_job.c: static int ivpu_job_submit(struct ivpu_job *job,
      	}
      
      	ret = ivpu_cmdq_push_job(cmdq, job);
    -@@ drivers/accel/ivpu/ivpu_job.c: static int ivpu_job_submit(struct ivpu_job *job, u8 priority, u32 cmdq_id)
    - 		 job->job_id, file_priv->ctx.id, job->engine_idx, cmdq->priority,
    +@@ drivers/accel/ivpu/ivpu_job.c: static int ivpu_job_submit(struct ivpu_job *job, u8 priority)
    + 		 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);
---

Results of testing on various branches:

| Branch                    | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-5.4.y        |  Success    |  Success   |