Re: [PATCH 1/3] media: verisilicon: Fix the cleanup when a codec ->run() fails
Benjamin Gaignard <[email protected]>
| Newsgroups | org.kernel.vger.linux-media,org.infradead.lists.linux-arm-kernel,org.infradead.lists.linux-rockchip,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
Le 24/08/2026 à 08:39, Sascha Hauer a écrit :
> A codec ->run() operation that fails leaves three things behind, and they
> cannot be untangled one at a time, so fix them together.
>
> hantro_start_prepare_run() sets up the controls of the request attached
> to the source buffer, hantro_end_prepare_run() completes them again and
> arms the watchdog for the job that is about to be started. That pairing
> does not survive the error paths. The two ->run() operations that do
> reach hantro_end_prepare_run() arm a watchdog for a job that is never
> started: device_run() finishes the job synchronously via
> hantro_job_finish_no_pm() and nothing cancels the delayed work, so it
> expires two seconds later and aborts whatever unrelated job happens to be
> running by then.
>
> Split the two jobs hantro_end_prepare_run() would otherwise have to do.
> It keeps its meaning for the success path, complete the request and arm
> the watchdog, and a new hantro_abort_prepare_run() completes the request
> and nothing else for the error paths. Note the resulting invariant: after
> hantro_end_prepare_run() the ->run() operation must return 0, as the
> watchdog is armed and only the interrupt handler disarms it.
>
> rockchip_vpu981_av1_dec_run() then calls hantro_irq_done() on its error
> path and returns the error code to device_run(), which finishes the job a
> second time. The buffers have already been given back by then, so the
> second attempt trips the WARN_ON(!src) in hantro_job_finish_no_pm() and
> bails out. Without the watchdog change this at least reached the first
> finish by accident, because the cancel_delayed_work() in
> hantro_irq_done() returned true for the watchdog the error path had just
> armed. Neither behaviour is something to rely on, so drop the call and
> let device_run() clean the job up. No other codec calls hantro_irq_done()
> from ->run().
>
> That leaves device_run() itself. It takes a pm_runtime reference and
> enables the clocks, then on any subsequent failure jumps to a single
> err_cancel_job label that calls hantro_job_finish_no_pm() - which
> releases neither. Release the acquired resources there.
>
> This last part is what ties the three together. hantro_irq_done() ends up
> in hantro_job_finish(), which already drops the pm reference and disables
> the clocks, so as long as the AV1 error path still goes through it,
> releasing the same resources in device_run() would trip the
>
> WARN_ON(core->enable_count == 0)
>
> in clk_core_disable() and underflow dev->power.usage_count. Conversely,
> as soon as a failed job no longer arms the watchdog, hantro_irq_done()
> stops releasing anything at all and the resources are leaked until
> device_run() takes over.
>
> The late_postproc setup is skipped on the error path as well. It is part
> of preparing the run, the hardware is not started and the next job
> configures it again, so hantro_abort_prepare_run() simply does not have
> it. Only the sunxi variant sets late_postproc, and its only decoder is
> VP9.
>
> Fixes: 892bb6ecead9 ("media: hantro: do a PM resume earlier")
> Fixes: e2da465455ce ("media: hantro: Support VP9 on the G2 core")
> Fixes: 727a400686a2 ("media: verisilicon: Add Rockchip AV1 decoder")
> Assisted-by: Claude:claude-opus-5
> Signed-off-by: Sascha Hauer <[email protected]>
Reviewed-by Benjamin Gaignard <[email protected]>
> ---
> drivers/media/platform/verisilicon/hantro_drv.c | 35 ++++++++++++++++++++--
> .../media/platform/verisilicon/hantro_g2_vp9_dec.c | 2 +-
> drivers/media/platform/verisilicon/hantro_hw.h | 1 +
> .../verisilicon/rockchip_vpu981_hw_av1_dec.c | 3 +-
> 4 files changed, 36 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/media/platform/verisilicon/hantro_drv.c b/drivers/media/platform/verisilicon/hantro_drv.c
> index ad71c0402ef3b..a9ebf856096e6 100644
> --- a/drivers/media/platform/verisilicon/hantro_drv.c
> +++ b/drivers/media/platform/verisilicon/hantro_drv.c
> @@ -147,6 +147,18 @@ void hantro_start_prepare_run(struct hantro_ctx *ctx)
> }
> }
>
> +/**
> + * hantro_end_prepare_run() - finish the preparation of a job and arm the
> + * watchdog
> + * @ctx: context the job belongs to
> + *
> + * Complete the controls of the request that hantro_start_prepare_run() set up
> + * and arm the watchdog. The caller must go on and start the hardware, as only
> + * the interrupt handler disarms the watchdog again.
> + *
> + * A ->run() operation that gives up before the hardware is started must call
> + * hantro_abort_prepare_run() instead.
> + */
> void hantro_end_prepare_run(struct hantro_ctx *ctx)
> {
> struct vb2_v4l2_buffer *src_buf;
> @@ -167,6 +179,21 @@ void hantro_end_prepare_run(struct hantro_ctx *ctx)
> msecs_to_jiffies(2000));
> }
>
> +/**
> + * hantro_abort_prepare_run() - give up on a job before the hardware is started
> + * @ctx: context the job belongs to
> + *
> + * Counterpart of hantro_end_prepare_run() for the error paths of ->run().
> + */
> +void hantro_abort_prepare_run(struct hantro_ctx *ctx)
> +{
> + struct vb2_v4l2_buffer *src_buf;
> +
> + src_buf = hantro_get_src_buf(ctx);
> + v4l2_ctrl_request_complete(src_buf->vb2_buf.req_obj.req,
> + &ctx->ctrl_handler);
> +}
> +
> static void device_run(void *priv)
> {
> struct hantro_ctx *ctx = priv;
> @@ -182,15 +209,19 @@ static void device_run(void *priv)
>
> ret = clk_bulk_enable(ctx->dev->variant->num_clocks, ctx->dev->clocks);
> if (ret)
> - goto err_cancel_job;
> + goto err_pm_put;
>
> v4l2_m2m_buf_copy_metadata(src, dst);
>
> if (ctx->codec_ops->run(ctx))
> - goto err_cancel_job;
> + goto err_clk_disable;
>
> return;
>
> +err_clk_disable:
> + clk_bulk_disable(ctx->dev->variant->num_clocks, ctx->dev->clocks);
> +err_pm_put:
> + pm_runtime_put_autosuspend(ctx->dev->dev);
> err_cancel_job:
> hantro_job_finish_no_pm(ctx->dev, ctx, VB2_BUF_STATE_ERROR);
> }
> diff --git a/drivers/media/platform/verisilicon/hantro_g2_vp9_dec.c b/drivers/media/platform/verisilicon/hantro_g2_vp9_dec.c
> index 56c79e339030e..78100d1c7e850 100644
> --- a/drivers/media/platform/verisilicon/hantro_g2_vp9_dec.c
> +++ b/drivers/media/platform/verisilicon/hantro_g2_vp9_dec.c
> @@ -895,7 +895,7 @@ int hantro_g2_vp9_dec_run(struct hantro_ctx *ctx)
>
> ret = start_prepare_run(ctx, &decode_params);
> if (ret) {
> - hantro_end_prepare_run(ctx);
> + hantro_abort_prepare_run(ctx);
> return ret;
> }
>
> diff --git a/drivers/media/platform/verisilicon/hantro_hw.h b/drivers/media/platform/verisilicon/hantro_hw.h
> index 13e573f1f19de..c6addab4d758b 100644
> --- a/drivers/media/platform/verisilicon/hantro_hw.h
> +++ b/drivers/media/platform/verisilicon/hantro_hw.h
> @@ -431,6 +431,7 @@ void hantro_irq_done(struct hantro_dev *vpu,
> enum vb2_buffer_state result);
> void hantro_start_prepare_run(struct hantro_ctx *ctx);
> void hantro_end_prepare_run(struct hantro_ctx *ctx);
> +void hantro_abort_prepare_run(struct hantro_ctx *ctx);
>
> irqreturn_t hantro_g1_irq(int irq, void *dev_id);
> void hantro_g1_reset(struct hantro_ctx *ctx);
> diff --git a/drivers/media/platform/verisilicon/rockchip_vpu981_hw_av1_dec.c b/drivers/media/platform/verisilicon/rockchip_vpu981_hw_av1_dec.c
> index e4e21ad373233..99ffb4a743764 100644
> --- a/drivers/media/platform/verisilicon/rockchip_vpu981_hw_av1_dec.c
> +++ b/drivers/media/platform/verisilicon/rockchip_vpu981_hw_av1_dec.c
> @@ -2192,8 +2192,7 @@ int rockchip_vpu981_av1_dec_run(struct hantro_ctx *ctx)
> return 0;
>
> prepare_error:
> - hantro_end_prepare_run(ctx);
> - hantro_irq_done(vpu, VB2_BUF_STATE_ERROR);
> + hantro_abort_prepare_run(ctx);
> return ret;
> }
>
>