Re: mlockall and mmap of IO devices don't mix

Joe Korty
2004-05-25T14:27:31Z

On Fri, May 21, 2004 at 07:13:26PM -0700, Andrew Morton wrote:
> Mark Hounschell <markh@compro.net> wrote:
> >
> > Joe Korty wrote:
> > >
> > > 2.6.0-test6: the use of mlockall(2) in a process that has mmap(2)ed
> > > the registers of an IO device will hang that process uninterruptibly.
> > > The task runs in an infinite loop in get_user_pages(), invoking
> > > follow_page() forever.
> > >
> > > Using binary search I discovered that the problem was introduced
> > > in 2.5.14, specifically in ChangeSetKey
> > >
> > > zippel@linux-m68k.org|ChangeSet|20020503210330|37095
> > >
> >
> > I know this is an old thread but can anyone tell me if this problem is
> > resolved in the current 2.6.6 kernel?
> >
>
> There's an utterly ancient patch in -mm which might fix this.
>
> http://www.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.6/2.6.6-mm4/broken-out/get_user_pages-handle-VM_IO.patch

[ 2nd send -- corporate email system in the throes of being scrambled / updated ]

Andrew,
I have been using this patch for ages. Any chance of it being forwared to
the official tree?

Regards,
Joe