On Thu, Nov 15, 2018 at 12:45:04PM -0500, Sasha Levin wrote: > On Wed, Nov 14, 2018 at 02:52:23PM +0900, Minchan Kim wrote: > > commit fef912bf860e upstream. > > commit 98af4d4df889 upstream. > > > > I got a report from Howard Chen that he saw zram and sysfs race(ie, > > zram block device file is created but sysfs for it isn't yet) > > when he tried to create new zram devices via hotadd knob. > > > > v4.20 kernel fixes it by [1, 2] but it's too large size to merge > > into -stable so this patch fixes the problem by registering defualt > > group by Greg KH's approach[3]. > > > > This patch should be applied to every stable tree [3.16+] currently > > existing from kernel.org because the problem was introduced at 2.6.37 > > by [4]. > > > > [1] fef912bf860e, block: genhd: add 'groups' argument to device_add_disk > > [2] 98af4d4df889, zram: register default groups with device_add_disk() > > [3] http://kroah.com/log/blog/2013/06/26/how-to-create-a-sysfs-file-correctly/ > > [4] 33863c21e69e9, Staging: zram: Replace ioctls with sysfs interface > > > > Cc: Sergey Senozhatsky <sergey.senozhatsky@xxxxxxxxx> > > Cc: Hannes Reinecke <hare@xxxxxxxx> > > Tested-by: Howard Chen <howardsoc@xxxxxxxxxx> > > Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx> > > I've queued this for 4.19 and 4.18, but it doesn't apply to anything > older than that. Thanks for the review, Hannes. Sasha, I will send separate patches for older stable kernel. Thanks for picking the patch. > > -- > Thanks, > Sasha
