[V1] remoteproc: virtio: Fix wdg cannot recovery remote processor

Commit Message

Joakim Zhang Dec. 12, 2023, 5:23 a.m. UTC

From: Joakim Zhang <[e-mail]>

Recovery remote processor failed when wdg irq received:
[    0.842574] remoteproc remoteproc0: crash detected in cix-dsp-rproc: type watchdog
[    0.842750] remoteproc remoteproc0: handling crash #1 in cix-dsp-rproc
[    0.842824] remoteproc remoteproc0: recovering cix-dsp-rproc
[    0.843342] remoteproc remoteproc0: stopped remote processor cix-dsp-rproc
[    0.847901] rproc-virtio rproc-virtio.0.auto: Failed to associate buffer
[    0.847979] remoteproc remoteproc0: failed to probe subdevices for cix-dsp-rproc: -16

The reason is that dma coherent mem would not be released when
recovering the remote processor, due to rproc_virtio_remove()
would not be called, where the mem released. It will fail when
it try to allocate and associate buffer again.

We can see that dma coherent mem allocated from rproc_add_virtio_dev(),
so should release it from rproc_remove_virtio_dev(). These functions should
appear symmetrically:
-rproc_vdev_do_start()->rproc_add_virtio_dev()->dma_declare_coherent_memory()
-rproc_vdev_do_stop()->rproc_remove_virtio_dev()->dma_release_coherent_memory()

Fixes: 1d7b61c06dc3 ("remoteproc: virtio: Create platform device for the remoteproc_virtio")
Signed-off-by: Joakim Zhang <[e-mail]>
---
 drivers/remoteproc/remoteproc_virtio.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Comments

Joakim Zhang Dec. 12, 2023, 2:11 p.m. UTC | #1

Hello maintainers,

This patch may not fix it in a correct way, after applying this patch, in rproc_add_virtio_dev():

1) If the allocate path is dma_declare_coherent_memory(), it will be freed from dma_release_coherent_memory(), which is expected

2) If the allocate path is of_reserved_mem_device_init_by_idx(), it will still be freed from dma_release_coherent_memory(), which is not expected

Try to fix this issue, I also introduce another patch: https://lore.kernel.org/lkml/[e-mail]/T/

Are there any suggestions? Thanks.

Joakim

> -----邮件原件-----
> 发件人: Joakim Zhang <[e-mail]>
> 发送时间: 2023年12月12日 13:24
> 收件人: [e-mail]; [e-mail];
> [e-mail]
> 抄送: [e-mail]; [e-mail];
> cix-kernel-upstream <[e-mail]>; Joakim Zhang
> <[e-mail]>
> 主题: [PATCH V1] remoteproc: virtio: Fix wdg cannot recovery remote
> processor
> 
> From: Joakim Zhang <[e-mail]>
> 
> Recovery remote processor failed when wdg irq received:
> [    0.842574] remoteproc remoteproc0: crash detected in cix-dsp-rproc:
> type watchdog
> [    0.842750] remoteproc remoteproc0: handling crash #1 in cix-dsp-rproc
> [    0.842824] remoteproc remoteproc0: recovering cix-dsp-rproc
> [    0.843342] remoteproc remoteproc0: stopped remote processor
> cix-dsp-rproc
> [    0.847901] rproc-virtio rproc-virtio.0.auto: Failed to associate buffer
> [    0.847979] remoteproc remoteproc0: failed to probe subdevices for
> cix-dsp-rproc: -16
> 
> The reason is that dma coherent mem would not be released when recovering
> the remote processor, due to rproc_virtio_remove() would not be called, where
> the mem released. It will fail when it try to allocate and associate buffer again.
> 
> We can see that dma coherent mem allocated from rproc_add_virtio_dev(), so
> should release it from rproc_remove_virtio_dev(). These functions should
> appear symmetrically:
> -rproc_vdev_do_start()->rproc_add_virtio_dev()->dma_declare_coherent_mem
> ory()
> -rproc_vdev_do_stop()->rproc_remove_virtio_dev()->dma_release_coherent_m
> emory()
> 
> Fixes: 1d7b61c06dc3 ("remoteproc: virtio: Create platform device for the
> remoteproc_virtio")
> Signed-off-by: Joakim Zhang <[e-mail]>
> ---
>  drivers/remoteproc/remoteproc_virtio.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/remoteproc/remoteproc_virtio.c
> b/drivers/remoteproc/remoteproc_virtio.c
> index 83d76915a6ad..725b957ee226 100644
> --- a/drivers/remoteproc/remoteproc_virtio.c
> +++ b/drivers/remoteproc/remoteproc_virtio.c
> @@ -465,8 +465,12 @@ static int rproc_add_virtio_dev(struct rproc_vdev
> *rvdev, int id)  static int rproc_remove_virtio_dev(struct device *dev, void
> *data)  {
>  	struct virtio_device *vdev = dev_to_virtio(dev);
> +	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
> 
>  	unregister_virtio_device(vdev);
> +
> +	dma_release_coherent_memory(&rvdev->pdev->dev);
> +
>  	return 0;
>  }
> 
> @@ -585,7 +589,6 @@ static void rproc_virtio_remove(struct platform_device
> *pdev)
>  	rproc_remove_rvdev(rvdev);
> 
>  	of_reserved_mem_device_release(&pdev->dev);
> -	dma_release_coherent_memory(&pdev->dev);
> 
>  	put_device(&rproc->dev);
>  }
> --
> 2.25.1

Patch

diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c
index 83d76915a6ad..725b957ee226 100644
--- a/drivers/remoteproc/remoteproc_virtio.c
+++ b/drivers/remoteproc/remoteproc_virtio.c
@@ -465,8 +465,12 @@  static int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)
 static int rproc_remove_virtio_dev(struct device *dev, void *data)
 {
 	struct virtio_device *vdev = dev_to_virtio(dev);
+	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
 
 	unregister_virtio_device(vdev);
+
+	dma_release_coherent_memory(&rvdev->pdev->dev);
+
 	return 0;
 }
 
@@ -585,7 +589,6 @@  static void rproc_virtio_remove(struct platform_device *pdev)
 	rproc_remove_rvdev(rvdev);
 
 	of_reserved_mem_device_release(&pdev->dev);
-	dma_release_coherent_memory(&pdev->dev);
 
 	put_device(&rproc->dev);
 }