Re: [RFC PATCH 0/4] file: export functions for binder module

[Al Viro]

On Mon, Jul 30, 2018 at 10:28:40PM +0200, Christian Brauner wrote:
> On Mon, Jul 30, 2018 at 01:19:47PM -0700, Matthew Wilcox wrote:
> > On Mon, Jul 30, 2018 at 10:12:24PM +0200, Christian Brauner wrote:
> > > > I don't expect this patch to be mergeable but rather to kick-off a
> > > > discussion if we can either simply export them as they are or how we can
> > > > get supportable exports that allow access to struct files_struct.
> > > 
> > > Maybe that wasn't obvious from the first message. Is there any way we
> > > can come up with a way to have versions of these functions that you
> > > would be fine with exporting?
> > > The point is that otherwise we would have to either duplicate the code
> > > or come up with something way more complex. If you have any pointer that
> > > would already help.
> > 
> > He said in the first reply this should probably be using an anonfd.
> > If you do that, I think all four of these exports go away.
> 
> I try and see if that is possible.
> 
> > 
> > And there was really no reason to post each of the four exports as
> > separate patches.  That just makes review harder on everyone.
> 
> Sorry about that. It usually depends on the preferences of each
> maintainer how fine-grained such minor changes should be.

The fundamental problem here (besides "who the hell thought that this Fine Piece
Of Software belongs anywhere other than in /dev/null?") is that messing with
other's descriptor table is Fucking Wrong(tm).  It's not going to become
a general-purpose interface.  That kludge is just that - a kludge caused by
atrocious API design.

Exports NAKed, and if brought again they'll get NAKed with extreme prejudice
(sensu PTerry).