Re: Hole punching and mmap races
From: Dave Chinner <david@fromorbit.com>
Date: 2012-05-18 10:12:10
Also in:
linux-fsdevel, linux-mm, linux-xfs
On Fri, May 18, 2012 at 01:28:29AM +0200, Jan Kara wrote:
On Thu 17-05-12 17:43:08, Dave Chinner wrote:quoted
On Wed, May 16, 2012 at 03:04:45PM +0200, Jan Kara wrote:quoted
On Wed 16-05-12 12:14:23, Dave Chinner wrote:IIRC, it's a rare case (that I consider insane, BTW): read from a file with into a buffer that is a mmap()d region of the same file that has not been faulted in yet.....With punch hole, the race is less insane - just punching hole in the area which is accessed via mmap could race in a bad way AFAICS.
Seems the simple answer to me is to prevent page faults while hole punching, then.... Cheers, Dave. -- Dave Chinner david@fromorbit.com