From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [git pull] gadgetfs fixes
Date: Sun, 15 Mar 2015 08:17:34 +0000
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-usb@vger.kernel.org
To: Alexander Holler <holler@ahsoftware.de>
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On Sun, Mar 15, 2015 at 07:35:20AM +0100, Alexander Holler wrote:

> > Umm...  If I'm not misparsing what you said, you are talking about =
the
>=20
> Gl=FCcklicherweise nicht. Vielleicht sollten wir es zur Abwechslung m=
al
> mit meiner bevorzugten Sprache versuchen.

Good.  I'll probably abstain from trying to mangle it, though.

Another question, if you don't mind - does that series (i.e. what's cur=
rently
in Linus' tree) fix the module refcount issues you'd been seeing?  I ag=
ree
with your analysis of likely cause (->f_op reassignments with different
->owner before and after) and these patches should have eliminated that=
, but
confirmation would be nice...

Incidentally, none of those file_operations need ->owner in the first p=
lace;
it doesn't hurt (as long as ->f_op doesn't change that way), but such f=
iles
(living on a filesystem provided by the module their methods are in)
don't need the module refcount bumped while the file is opened - having=
 it
opened pins file_system_type of containing filesystem (by keeping a ref=
erence
to struct vfsmount, which keeps a reference to struct super_block, whic=
h keeps
a reference to file_system_type), so the module will be kept busy just =
fine.
Again, having ->owner on file_operations doesn't hurt, so it's not a bu=
g
per se - just pointless in such cases.  So we might want to remove it
from ep_io_operations someday.  Anyway, that's a completely separate st=
ory...