Re: [PATCH] block: hide badblocks attribute by default

["Verma, Vishal L" <vishal.l.verma@intel.com>]

On Thu, 2017-04-27 at 14:46 -0700, Dan Williams wrote:
> Commit 99e6608c9e74 "block: Add badblock management for gendisks"
> allowed for drivers like pmem and software-raid to advertise a list of
> bad media areas. However, it inadvertently added a 'badblocks' to all
> block devices. Lets clean this up by having the 'badblocks' attribute
> not be visible when the driver has not populated a 'struct badblocks'
> instance in the gendisk.
> 
> Cc: Jens Axboe <axboe@fb.com>
> Cc: Christoph Hellwig <hch@lst.de>
> Cc: Martin K. Petersen <martin.petersen@oracle.com>
> Reported-by: Vishal Verma <vishal.l.verma@intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> ---
>  block/genhd.c |   11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
Tested that this removes the badblocks attribute for block devices that
don't use them:

$ cat /sys/block/pmem6/badblocks 
61576 8

$ cat /sys/block/vda/badblocks 
cat: /sys/block/vda/badblocks: No such file or directory

Tested-by: Vishal Verma <vishal.l.verma@intel.com>