pipe() resource exhaustion

[Mateusz Guzik]

On Wed, Apr 09, 2014 at 02:26:27PM +0300, Konstantin Belousov wrote:
> >  	if (backing) {
> > +		/*
> > +		 * Note that these functions can fail, but we ignore
> > +		 * the error as it is not fatal and could be provoked
> > +		 * by users.
> > +		 */
> It would be benefitial to add some more details on the way to provoke the
> failure.  Note in the comment that creating too much pipes would exhaust
> pipe map and we fall back to the buffer pipe creation there, which still
> work correctly, albeit slow.
> 

How about:

Note that these functions can fail if pipe map is exhausted (as a result
of too many pipes created), but we ignore the error as it is not fatal
and could be provoked by unprivileged users. The only consequence is worse
performance with given pipe.

-- 
Mateusz Guzik <mjguzik gmail.com>