Re: [RFC PATCH] Implement /proc/pid/kill

From: Christian Brauner
Date: Fri Nov 02 2018 - 05:46:14 EST


On Thu, Nov 01, 2018 at 01:40:59PM -0700, Joel Fernandes wrote:
> On Tue, Oct 30, 2018 at 09:24:00PM -0700, Joel Fernandes wrote:
> > On Tue, Oct 30, 2018 at 7:56 PM, Aleksa Sarai <cyphar@xxxxxxxxxx> wrote:
> > > On 2018-10-31, Christian Brauner <christian.brauner@xxxxxxxxxxxxx> wrote:
> > >> > I think Aleksa's larger point is that it's useful to treat processes
> > >> > as other file-descriptor-named, poll-able, wait-able resources.
> > >> > Consistency is important. A process is just another system resource,
> > >> > and like any other system resource, you should be open to hold a file
> > >> > descriptor to it and do things to that process via that file
> > >> > descriptor. The precise form of this process-handle FD is up for
> > >> > debate. The existing /proc/$PID directory FD is a good candidate for a
> > >> > process handle FD, since it does almost all of what's needed. But
> > >> > regardless of what form a process handle FD takes, we need it. I don't
> > >> > see a case for continuing to treat processes in a non-unixy,
> > >> > non-file-descriptor-based manner.
> > >>
> > >> That's what I'm proposing in the API for which I'm gathering feedback.
> > >> I have presented parts of this in various discussions at LSS Europe last week
> > >> and will be at LPC.
> > >> We don't want to rush an API like this though. It was tried before in
> > >> other forms
> > >> and these proposals didn't make it.
> > >
> > > :+1: on a well thought-out and generic proposal. As we've discussed
> > > elsewhere, this is an issue that really would be great to (finally)
> > > solve.
> >
> > Excited to see this and please count me in for discussions around this. thanks.
> >
>
> Just a quick question, is there a track planned at LPC for discussing this
> new proposal or topics around/related to the proposal?
>
> If not, should that be planned?

There isn't currently one planned but I'm happy to have a hallway track
session around this.

But note, I think not all relevant people are going to be there (e.g.
Andy). File descriptors for processes seems interesting to a lot of
people so I'm going to send out a pitch of the idea I have and see how
much I'm going to get yelled at latest on Tuesday. Even if it just
triggers a design discussion.
I have been urged by people I pitched this to to send it to lkml
already. Sorry for the delay and the initial non-transparency. The only
reason I didn't do it right away was to ensure that this idea is not
completely crazy. :) (Eric probably still thinks I am though. :))
It's just that I'm at a conference and I want to have a nicer writeup of
this. Given the speed with which this is all coming I have given up on
preparing a first set of patches. :)

Christian