Re: [PATCH] libnvdimm, namespace: do not delete namespace-id 0

[Johannes Thumshirn <jthumshirn@suse.de>]

On Wed, Feb 01, 2017 at 10:35:21AM -0800, Dan Williams wrote:
> Given that the naming of pmem devices changes from the pmemX form to the
> pmemX.Y form when namespace id is greater than 0, arrange for namespaces
> with id-0 to be exempt from deletion. Otherwise a simple reconfiguration
> of an existing namespace to a new mode results in a name change of the
> resulting block device:
> 
>     # ndctl list --namespace=namespace1.0
>     {
>       "dev":"namespace1.0",
>       "mode":"raw",
>       "size":2147483648,
>       "uuid":"3dadf3dc-89b9-4b24-b20e-abc8a4707ce3",
>       "blockdev":"pmem1"
>     }
> 
>     # ndctl create-namespace --reconfig=namespace1.0 --mode=memory --force
>     {
>       "dev":"namespace1.1",
>       "mode":"memory",
>       "size":2111832064,
>       "uuid":"7b4a6341-7318-4219-a02c-fb57c0bbf613",
>       "blockdev":"pmem1.1"
>     }
> 
> This change does require tooling changes to explicitly look for
> namespaceX.0 if the seed has already advanced to another namespace.
> 
> Cc: <stable@vger.kernel.org>
> Fixes: 98a29c39dc68 ("libnvdimm, namespace: allow creation of multiple pmem-namespaces per region")
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> ---

Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

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