accel/amdxdna: Fix deadlock between context destroy and job timeout

Hardware context destroy function holds dev_lock while waiting for all jobs
to complete. The timeout job also needs to acquire dev_lock, this leads to
a deadlock.

Fix the issue by temporarily releasing dev_lock before waiting for all
jobs to finish, and reacquiring it afterward.

Fixes: 4fd6ca90fc7f ("accel/amdxdna: Refactor hardware context destroy routine")
Reviewed-by: Maciej Falkowski <maciej.falkowski@linux.intel.com>
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Link: https://patch.msgid.link/20251107181050.1293125-1-lizhi.hou@amd.com

diff --git a/drivers/accel/amdxdna/aie2_ctx.c b/drivers/accel/amdxdna/aie2_ctx.c
index bdc90fe8a47eed2828b1674c472439f0ea707d64..42d876a427c5950c13e574e46549a4a6e9d64102 100644 (file)
--- a/drivers/accel/amdxdna/aie2_ctx.c
+++ b/drivers/accel/amdxdna/aie2_ctx.c
@@ -690,17 +690,19 @@ void aie2_hwctx_fini(struct amdxdna_hwctx *hwctx)
        xdna = hwctx->client->xdna;
 
        XDNA_DBG(xdna, "%s sequence number %lld", hwctx->name, hwctx->priv->seq);
-       drm_sched_entity_destroy(&hwctx->priv->entity);
-
        aie2_hwctx_wait_for_idle(hwctx);
 
        /* Request fw to destroy hwctx and cancel the rest pending requests */
        aie2_release_resource(hwctx);
 
+       mutex_unlock(&xdna->dev_lock);
+       drm_sched_entity_destroy(&hwctx->priv->entity);
+
        /* Wait for all submitted jobs to be completed or canceled */
        wait_event(hwctx->priv->job_free_wq,
                   atomic64_read(&hwctx->job_submit_cnt) ==
                   atomic64_read(&hwctx->job_free_cnt));
+       mutex_lock(&xdna->dev_lock);
 
        drm_sched_fini(&hwctx->priv->sched);
        aie2_ctx_syncobj_destroy(hwctx);