[PATCH 1/3] arm/syscalls: Move address limit check in loop

[Leonard Crestez]

On Mon, 2017-07-24 at 10:07 -0700, Thomas Garnier wrote:
> On Wed, Jul 19, 2017 at 10:58 AM, Thomas Garnier <thgarnie at google.com
> > wrote:
> > 
> > The work pending loop can call set_fs after addr_limit_user_check
> > removed the _TIF_FSCHECK flag. To prevent the infinite loop, move
> > the addr_limit_user_check call at the beginning of the loop.
> > 
> > Fixes: 73ac5d6a2b6a ("arm/syscalls: Check address limit on user-
> > mode return")
> > Reported-by: Leonard Crestez <leonard.crestez at nxp.com>
> > Signed-off-by: Thomas Garnier <thgarnie at google.com>

> Any comments on this patch set?

Tested-by: Leonard Crestez <leonard.crestez at nxp.com>

This appears to fix the original issue of failing to boot from NFS when
there are lots of alignment faults. But this is a very basic test
relative to the reach of this change.

However the original patch has been in linux-next for a while and
apparently nobody else noticed system calls randomly hanging on arm.

I assume maintainers need to give their opinion.