Re: [PATCH] mm/mincore: allow for making sys_mincore() privileged

From: Kevin Easton
Date: Wed Jan 16 2019 - 07:18:19 EST


On Tue, Jan 15, 2019 at 11:52:25PM -0800, Josh Snyder wrote:
> On Tue, Jan 15, 2019 at 10:34 PM Dominique Martinet <asmadeus@xxxxxxxxxxxxx>
> wrote:
> >
> > There is a difference with your previous patch though, that used to list no
> > page in core when it didn't know; this patch lists pages as in core when it
> > refuses to tell. I don't think that's very important, though.
>
> Is there a reason not to return -EPERM in this case?

When I was looking through the Debian Code Search results, quite a few
of the hits were for code that uses mincore() as a way to check if
_anything_ is mapped at an address or not. This code doesn't care about
the in core / not in core result of mincore(), just whether it returned
an error or not.

I think a new error return would break most of the instances of that
code I saw.

- Kevin