[PATCHv2] nvme-mpath: delete disk after last connection

[Keith Busch]

On Fri, Apr 16, 2021 at 08:24:11AM +0200, Hannes Reinecke wrote:
> Now delete all paths to one of the namespaces:
> 
>  # echo 1 > /sys/class/nvme/nvme3/delete_controller
>  # echo 1 > /sys/class/nvme/nvme4/delete_controller
> 
> We have no path, but mdstat says:
> 
>  # cat /proc/mdstat
>  Personalities : [raid1]
>  md0 : active (auto-read-only) raid1 nvme5n1[1]
>        64512 blocks super 1.2 [2/1] [_U]
> 
> And this is reported to cause a problem.
> 
> With the proposed patch, the following messages appear:
> 
>  [  227.516807] md/raid1:md0: Disk failure on nvme3n1, disabling device.
>  [  227.516807] md/raid1:md0: Operation continuing on 1 devices.
> 
> And mdstat shows only the viable members:
> 
>  # cat /proc/mdstat
>  Personalities : [raid1]
>  md0 : active (auto-read-only) raid1 nvme5n1[1]
>        64512 blocks super 1.2 [2/1] [_U]

I think there's a copy-paste error in this change log (probably my
mistake). The first mdstat should have shown nvme3n1 was still there,
right?