The vdec driver was incorrectly initializing a new v4l2_m2m device instance per session inside vdec_open() and releasing it in vdec_close(). This design is faulty because the m2m device models the core hardware engine and must persist across multiple sessions.
Fix the lifetime by moving v4l2_m2m_init() into vdec_probe() and releasing it in vdec_remove() which resolves passing the global core->m2m_dev down to session contexts so all sessions share the same hardware instance. This change aligns the driver with proper v4l2_m2m usage, ensuring the hardware device lifetime is tied to the platform driver core, not individual sessions, and making teardown safe and predictable. Reported-by: Sashiko <[email protected]> Closes: https://lore.kernel.org/all/[email protected]/#t Signed-off-by: Anand Moon <[email protected]> --- drivers/staging/media/meson/vdec/vdec.c | 36 +++++++++++++------------ drivers/staging/media/meson/vdec/vdec.h | 4 +-- 2 files changed, 21 insertions(+), 19 deletions(-) diff --git a/drivers/staging/media/meson/vdec/vdec.c b/drivers/staging/media/meson/vdec/vdec.c index a039d925c0fe5..6ae3471155a87 100644 --- a/drivers/staging/media/meson/vdec/vdec.c +++ b/drivers/staging/media/meson/vdec/vdec.c @@ -153,7 +153,7 @@ static void vdec_m2m_job_abort(void *priv) { struct amvdec_session *sess = priv; - v4l2_m2m_job_finish(sess->m2m_dev, sess->m2m_ctx); + v4l2_m2m_job_finish(sess->core->m2m_dev, sess->m2m_ctx); } static const struct v4l2_m2m_ops vdec_m2m_ops = { @@ -873,23 +873,16 @@ static int vdec_open(struct file *file) sess->core = core; - sess->m2m_dev = v4l2_m2m_init(&vdec_m2m_ops); - if (IS_ERR(sess->m2m_dev)) { - dev_err(dev, "Fail to v4l2_m2m_init\n"); - ret = PTR_ERR(sess->m2m_dev); - goto err_free_sess; - } - - sess->m2m_ctx = v4l2_m2m_ctx_init(sess->m2m_dev, sess, m2m_queue_init); + sess->m2m_ctx = v4l2_m2m_ctx_init(core->m2m_dev, sess, m2m_queue_init); if (IS_ERR(sess->m2m_ctx)) { dev_err(dev, "Fail to v4l2_m2m_ctx_init\n"); ret = PTR_ERR(sess->m2m_ctx); - goto err_m2m_release; + goto err_free_sess; } ret = vdec_init_ctrls(sess); if (ret) - goto err_m2m_ctx_release; + goto err_release_ctx; sess->pixfmt_cap = formats[0].pixfmts_cap[0]; sess->fmt_out = &formats[0]; @@ -913,10 +906,8 @@ static int vdec_open(struct file *file) return 0; -err_m2m_ctx_release: +err_release_ctx: v4l2_m2m_ctx_release(sess->m2m_ctx); -err_m2m_release: - v4l2_m2m_release(sess->m2m_dev); err_free_sess: kfree(sess); return ret; @@ -927,9 +918,9 @@ static int vdec_close(struct file *file) struct amvdec_session *sess = file_to_amvdec_session(file); v4l2_m2m_ctx_release(sess->m2m_ctx); - v4l2_m2m_release(sess->m2m_dev); v4l2_fh_del(&sess->fh, file); v4l2_fh_exit(&sess->fh); + v4l2_ctrl_handler_free(&sess->ctrl_handler); mutex_destroy(&sess->lock); mutex_destroy(&sess->bufs_recycle_lock); @@ -1059,16 +1050,23 @@ static int vdec_probe(struct platform_device *pdev) if (ret) return ret; + core->m2m_dev = v4l2_m2m_init(&vdec_m2m_ops); + if (IS_ERR(core->m2m_dev)) { + dev_err(dev, "Failed to initialize v4l2 m2m device\n"); + return PTR_ERR(core->m2m_dev); + } + ret = v4l2_device_register(dev, &core->v4l2_dev); if (ret) { dev_err(dev, "Couldn't register v4l2 device\n"); - return -ENOMEM; + ret = -ENOMEM; + goto err_m2m_release; } vdev = video_device_alloc(); if (!vdev) { ret = -ENOMEM; - goto err_vdev_release; + goto err_v4l2_unregister; } core->vdev_dec = vdev; @@ -1096,7 +1094,10 @@ static int vdec_probe(struct platform_device *pdev) err_vdev_release: video_device_release(vdev); +err_v4l2_unregister: v4l2_device_unregister(&core->v4l2_dev); +err_m2m_release: + v4l2_m2m_release(core->m2m_dev); return ret; } @@ -1105,6 +1106,7 @@ static void vdec_remove(struct platform_device *pdev) struct amvdec_core *core = platform_get_drvdata(pdev); video_unregister_device(core->vdev_dec); + v4l2_m2m_release(core->m2m_dev); v4l2_device_unregister(&core->v4l2_dev); } diff --git a/drivers/staging/media/meson/vdec/vdec.h b/drivers/staging/media/meson/vdec/vdec.h index 7a5d8e871d708..cc0cfafb8a951 100644 --- a/drivers/staging/media/meson/vdec/vdec.h +++ b/drivers/staging/media/meson/vdec/vdec.h @@ -63,6 +63,7 @@ struct amvdec_session; * @vdec_hevcf_clk: VDEC_HEVCF clock * @esparser_reset: RESET for the PARSER * @vdev_dec: video device for the decoder + * @m2m_dev: v4l2 m2m device * @v4l2_dev: v4l2 device * @cur_sess: current decoding session * @lock: video device lock @@ -87,6 +88,7 @@ struct amvdec_core { struct reset_control *esparser_reset; struct video_device *vdev_dec; + struct v4l2_m2m_dev *m2m_dev; struct v4l2_device v4l2_dev; struct amvdec_session *cur_sess; @@ -183,7 +185,6 @@ enum amvdec_status { * * @core: reference to the vdec core struct * @fh: v4l2 file handle - * @m2m_dev: v4l2 m2m device * @m2m_ctx: v4l2 m2m context * @ctrl_handler: V4L2 control handler * @ctrl_min_buf_capture: V4L2 control V4L2_CID_MIN_BUFFERS_FOR_CAPTURE @@ -230,7 +231,6 @@ struct amvdec_session { struct amvdec_core *core; struct v4l2_fh fh; - struct v4l2_m2m_dev *m2m_dev; struct v4l2_m2m_ctx *m2m_ctx; struct v4l2_ctrl_handler ctrl_handler; struct v4l2_ctrl *ctrl_min_buf_capture; -- 2.50.1
