Re: [PATCH 3/4] nvme: Should not warn when a disk path is opened

[Hannes Reinecke <hare@suse.de>]

On 12/6/18 5:48 PM, Thadeu Lima de Souza Cascardo wrote:
> As we hide the disks used for nvme multipath, their open functions
> should be allowed to be called, as their devices are not exposed.
> 
> However, not exposing the devices cause problems with lsblk, which won't
> find the devices and show them, which is even more of a problem when
> holders/slaves relationships are exposed.
> 
> Not warning here allow us to expose the disks without creating spurious
> warnings. A failure should still be returned, which is the case here,
> and still allows lsblk to work.
> 
> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
> ---
>   drivers/nvme/host/core.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index 1dc29795f1ee..22424b2adfad 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -1327,8 +1327,8 @@ static int nvme_open(struct block_device *bdev, fmode_t mode)
>   	struct nvme_ns *ns = bdev->bd_disk->private_data;
>   
>   #ifdef CONFIG_NVME_MULTIPATH
> -	/* should never be called due to GENHD_FL_HIDDEN */
> -	if (WARN_ON_ONCE(ns->head->disk))
> +	/* Should fail as it's hidden */
> +	if (ns->head->disk)
>   		goto fail;
>   #endif
>   	if (!kref_get_unless_zero(&ns->kref))
> 
Reviewed-by: Hannes Reinecke <hare@suse.com>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		   Teamlead Storage & Networking
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