Re: [Ksummit-discuss] [MAINTAINERS SUMMIT] Moving debugfs file systems into sysfs

[Jan Kara <jack@suse.cz>]

On Wed 03-10-18 06:40:12, Greg Kroah-Hartman wrote:
> On Wed, Oct 03, 2018 at 02:59:16PM +0200, Jan Kara wrote:
> > On Tue 02-10-18 15:22:38, Greg Kroah-Hartman wrote:
> > > Luckily debugfs was made "root only by default" a while ago, to help
> > > mitigate this problem.  So while it is present on a number of distros,
> > > the "attack surface" is greatly reduced.
> > > 
> > > That being said, I bet those distros can drop those config options and
> > > be fine.
> > 
> > Not really. We need those configs to be enabled to be able to troubleshoot
> > customer's problems - e.g., asking customer to enable some trace points or
> > show some stats from debugfs is pretty common...
> 
> trace points should not be in debugfs.  And what stats are in debugfs
> that are not availble in other tools?  If you rely on them, shouldn't we
> move them to a "stable" location so that they can always be accessed?

I personally use e.g. stats under bdi/ directory. And I agree with Jiri
that these things are usually only useful when debugging problems so they
seem to match debugfs purpose rather well. We would not even need debugfs
*mounted* all the time I guess (but then what's the difference between
root-only access currently enforced and not having it mounted, right). But
we do need to have it compiled into the kernel...

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR