MIME-Version: 1.0
In-Reply-To: <CA+55aFyMa1dD65Fw-8X=3QfRtkdNfjxYLf4xeXS1n3Uej89VZA@mail.gmail.com>
References: <20170816171211.4021-1-christian.brauner@ubuntu.com>
 <CA+55aFzqedKjjq+FDF3AEgyQfqQRHyR-6PTR_BTvyyQLqnPwPw@mail.gmail.com>
 <CA+55aFyy1RU2emO6giU9gNVb_doYP+K_y61ij2cumgs1_VMMmA@mail.gmail.com>
 <20170816194805.hnof3aqiqykwki7p@gmail.com> <CA+55aFzmcydKsuwXpocd0hYMrACEXt+UUuaqa7j3L5LG7SjajQ@mail.gmail.com>
 <CA+55aFxMnEQVq8zRG1JEsW+6x23qkBV=KKXksgVHmBegPuepMg@mail.gmail.com>
 <CA+55aFz+qGxM9MidcvQkP4er-qn0_oEqCac=ob64f+twhptSgQ@mail.gmail.com>
 <CA+55aFxXzwoDdN72m2oaV4XuxO0DGoT+Bp84i07VFpLQ3Ftcpw@mail.gmail.com>
 <CAPP7u0WmLaSNTt3OCecy+uu=zm0D6FeZvKeMruA30BZnNXY24A@mail.gmail.com> <CA+55aFyMa1dD65Fw-8X=3QfRtkdNfjxYLf4xeXS1n3Uej89VZA@mail.gmail.com>
From: Christian Brauner <christian.brauner@canonical.com>
Date: Thu, 17 Aug 2017 00:28:45 +0200
Message-ID: <CAPP7u0W5288y+mb0w=LZdJA=OdTVsuByLEhTY2HHtvnytSOeMg@mail.gmail.com>
Subject: Re: [PATCH 0/1] devpts: use dynamic_dname() to generate proc name
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Christian Brauner <christian.brauner@ubuntu.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        Al Viro <viro@zeniv.linux.org.uk>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1546
Lines: 33

On Wed, Aug 16, 2017 at 11:45 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
> On Wed, Aug 16, 2017 at 2:37 PM, Christian Brauner
> <christian.brauner@canonical.com> wrote:
>>> And Christian, if you can beat on this, that would be good.
>>
>> Yes, I can pound on this nicely with liblxc. We have patch
>> ( https://github.com/lxc/lxc/pull/1728 ) up for review that
>> allocates pty fds from private devpts mounts in different namespaces
>> and sends those fds around between different namespaces.
>
> Good. Testing that this works with different pts filesystems in
> different places is exactly the kind of thing I'd like to see. I only
> tested with my single pts filesystem that is mounted at /dev/pts, and
> making sure it works when there are multiple mounts and in different
> places is exactly the kind of testing this should get.

I'm compiling a kernel now and depending on how good the in-flight
wifi is I try to test this right away and answer here if that helps. If the
in-flight wifi sucks it might take me until tomorrow.

>
> For example, if some namespace has it's pty's in _its_ /dev/pts/
> hierarchy, and you then pass such a pty to somebody else that either
> doesn't have that pts mount at all, or has it visible somewhere
> entirely different, the result should now be something else than that
> "/dev/pts/n" path.
>
> But it would be good to just test this in general too, and make sure I
> didn't screw up some reference count or something. The patch *looks*
> obviously correct, but ...
>
>                Linus