Re: [PATCH v1 1/2] proc: get process file descriptor from /proc/<pid>

From: Christian Brauner
Date: Mon Nov 19 2018 - 13:20:56 EST


On Mon, Nov 19, 2018 at 07:32:33AM -0800, Andy Lutomirski wrote:
> On Mon, Nov 19, 2018 at 2:33 AM Christian Brauner <christian@xxxxxxxxxx> wrote:
> >
> > With this patch an open() call on /proc/<pid> will give userspace a handle
> > to struct pid of the process associated with /proc/<pid>. This allows to
> > maintain a stable handle on a process.
> > I have been discussing various approaches extensively during technical
> > conferences this year culminating in a long argument with Eric at Linux
> > Plumbers. The general consensus was that having a handle on a process
> > should be something that is very simple and easy to maintain with the
> > option of being extensible via a more advanced api if the need arises. I
> > believe that this patch is the most simple, dumb, and therefore
> > maintainable solution.
>
> How does the mechanism you're adding here differ from proc_pid()?

I'm sorry, I am missing the context around proc_pid()?. Are you talking
about the the proc_pid() function in "internal.h"? What exactly is the
proc_pid() mechanism?