Re: [PATCH] prctl: Don't compile some of prctl functions when CRUI

From: Cyrill Gorcunov
Date: Wed Apr 17 2019 - 12:56:38 EST


On Wed, Apr 17, 2019 at 04:44:54PM +0200, Michal Koutný wrote:
> On Wed, Apr 17, 2019 at 03:38:41PM +0300, Cyrill Gorcunov <gorcunov@xxxxxxxxx> wrote:
> > I've a bit vague memory what we've ended up with, but iirc there was
> > a problem with brk() syscall or similar. Then I think we left everything
> > as is.
> Was this related to the removal of non PR_SET_MM_MAP operations too?
> Do you have any pointers to the topic?

Here some details: suprisingly there are already users of PR_SET_MM_x
operands, so we can't deprecate it (https://lkml.org/lkml/2018/5/6/127).
And then there was an attempt to change locks https://lore.kernel.org/patchwork/patch/
but since we're modifying mm-> entries we should gurd them against
simultaneous sys_brk call. Or I misunderstood you and you meant somthing
different?