Re: [PATCH v3] virtio_pmem: Check device status before requesting flush
From: Pankaj Gupta
Date: Mon Sep 09 2024 - 09:27:14 EST
+CC MST
> If a pmem device is in a bad status, the driver side could wait for
> host ack forever in virtio_pmem_flush(), causing the system to hang.
>
> So add a status check in the beginning of virtio_pmem_flush() to return
> early if the device is not activated.
>
> Signed-off-by: Philip Chen <philipchen@xxxxxxxxxxxx>
Looks good to me.
Acked-by: Pankaj Gupta <pankaj.gupta.linux@xxxxxxxxx
> ---
> v3:
> - Fix a typo in the comment (s/acticated/activated/)
>
> v2:
> - Remove change id from the patch description
> - Add more details to the patch description
>
> drivers/nvdimm/nd_virtio.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/nvdimm/nd_virtio.c b/drivers/nvdimm/nd_virtio.c
> index 35c8fbbba10e..f55d60922b87 100644
> --- a/drivers/nvdimm/nd_virtio.c
> +++ b/drivers/nvdimm/nd_virtio.c
> @@ -44,6 +44,15 @@ static int virtio_pmem_flush(struct nd_region *nd_region)
> unsigned long flags;
> int err, err1;
>
> + /*
> + * Don't bother to submit the request to the device if the device is
> + * not activated.
> + */
> + if (vdev->config->get_status(vdev) & VIRTIO_CONFIG_S_NEEDS_RESET) {
> + dev_info(&vdev->dev, "virtio pmem device needs a reset\n");
> + return -EIO;
> + }
> +
> might_sleep();
> req_data = kmalloc(sizeof(*req_data), GFP_KERNEL);
> if (!req_data)