Re: [PATCH v2] virtio_pmem: Check device status before requesting flush

[Dave Jiang]

On 8/20/24 10:22 AM, Philip Chen wrote:
> 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>
> ---
> 
> 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..97addba06539 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 acticated.

s/acticated/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)