btt device node disappeared after configure with non support sector_size

btt device node disappeared after configure with non support sector_size

[Yi Zhang]

Hi folks,

Seems I hit one issue that btt device node disappeared after configure with non support sector_size, could you help confirm it?

4.7.0
# ndctl create-namespace -f -e namespace0.0 --mode=sector  -l 512
{
  "dev":"namespace0.0",
  "mode":"sector",
  "uuid":"45b4900d-da76-47c8-956f-a70e4ea33fe3",
  "sector_size":512,
  "blockdev":"pmem0s"
}
# lsblk 
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
pmem0s 259:0    0     8G  0 disk 
pmem1s 259:2    0   7.1G  0 disk 
pmem2s 259:1    0   7.1G  0 disk 
pmem3s 259:3    0   7.1G  0 disk 
# ndctl create-namespace -f -e namespace0.0 --mode=sector  -l 513
failed to reconfigure namespace

# lsblk 
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
pmem1s 259:2    0   7.1G  0 disk 
pmem2s 259:1    0   7.1G  0 disk 
pmem3s 259:3    0   7.1G  0 disk 



Best Regards,
  Yi Zhang

Re: btt device node disappeared after configure with non support sector_size

[Dan Williams]

On Thu, Aug 4, 2016 at 2:15 AM, Yi Zhang <yizhan-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
> Hi folks,
>
> Seems I hit one issue that btt device node disappeared after configure with non support sector_size, could you help confirm it?
>
> 4.7.0
> # ndctl create-namespace -f -e namespace0.0 --mode=sector  -l 512
> {
>   "dev":"namespace0.0",
>   "mode":"sector",
>   "uuid":"45b4900d-da76-47c8-956f-a70e4ea33fe3",
>   "sector_size":512,
>   "blockdev":"pmem0s"
> }
> # lsblk
> NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
> pmem0s 259:0    0     8G  0 disk
> pmem1s 259:2    0   7.1G  0 disk
> pmem2s 259:1    0   7.1G  0 disk
> pmem3s 259:3    0   7.1G  0 disk
> # ndctl create-namespace -f -e namespace0.0 --mode=sector  -l 513
> failed to reconfigure namespace
>
> # lsblk
> NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
> pmem1s 259:2    0   7.1G  0 disk
> pmem2s 259:1    0   7.1G  0 disk
> pmem3s 259:3    0   7.1G  0 disk

This is expected if you specify invalid namespace values, but we
should be trapping this case and reporting a more useful error message
from ndctl rather than letting the kernel fail the namespace setup.

For now, you can fix this by re-configuring the namespace with valid values.

Re: btt device node disappeared after configure with non support sector_size

[yizhan]

On 08/04/2016 10:37 PM, Dan Williams wrote:
> On Thu, Aug 4, 2016 at 2:15 AM, Yi Zhang <yizhan-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
>> Hi folks,
>>
>> Seems I hit one issue that btt device node disappeared after configure with non support sector_size, could you help confirm it?
>>
>> 4.7.0
>> # ndctl create-namespace -f -e namespace0.0 --mode=sector  -l 512
>> {
>>    "dev":"namespace0.0",
>>    "mode":"sector",
>>    "uuid":"45b4900d-da76-47c8-956f-a70e4ea33fe3",
>>    "sector_size":512,
>>    "blockdev":"pmem0s"
>> }
>> # lsblk
>> NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
>> pmem0s 259:0    0     8G  0 disk
>> pmem1s 259:2    0   7.1G  0 disk
>> pmem2s 259:1    0   7.1G  0 disk
>> pmem3s 259:3    0   7.1G  0 disk
>> # ndctl create-namespace -f -e namespace0.0 --mode=sector  -l 513
>> failed to reconfigure namespace
>>
>> # lsblk
>> NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
>> pmem1s 259:2    0   7.1G  0 disk
>> pmem2s 259:1    0   7.1G  0 disk
>> pmem3s 259:3    0   7.1G  0 disk
> This is expected if you specify invalid namespace values, but we
> should be trapping this case and reporting a more useful error message
> from ndctl rather than letting the kernel fail the namespace setup.
>
> For now, you can fix this by re-configuring the namespace with valid values.
yes, I have re-configured with valid sector size and the pmem0s 
reconfigured.
I think it's better to let the pmem0s device node still exist and can be 
used rather than fail the kernel setup. :)

Thanks
Yi