Date: Thu, 24 Aug 2017 06:24:32 +0200
From: Stefan Lippers-Hollmann <s.l-h@gmx.de>
To: ebiederm@xmission.com (Eric W. Biederman)
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Christian Brauner <christian.brauner@canonical.com>,
        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>,
        Thorsten Leemhuis <regressions@leemhuis.info>
Subject: Re: [PATCH 0/1] devpts: use dynamic_dname() to generate proc name
Message-ID: <20170824062432.1e05e6f8@mir>
In-Reply-To: <87wp5tfynr.fsf@xmission.com>
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Hi

On 2017-08-23, Eric W. Biederman wrote:
> Linus Torvalds <torvalds@linux-foundation.org> writes:
> > On Wed, Aug 23, 2017 at 6:49 PM, Linus Torvalds <torvalds@linux-foundat=
ion.org> wrote: =20
[...]
> This is so far untested (except for compiling) but I think this will
> work.
>=20
> I factor out devpts_ptmx_path out of devpts_acquire so the code
> doesn't have to do unnecessary and confusing work, and add the
> new function devpts_mnt.
>=20
> I revert the code to keep anything except a dentry in
> tty->link->driver_data.
>=20
> And reduce the peer opening to a single function ptm_open_peer.
>=20
> It takes lines of code but the result is very straightforward code.

I've given this a quick test, while it seems to fix the initial problem
with umounting /dev/ptmx, it does introduce a new one - trying to open=20
an xterm (KDE5's konsole to be exact) doesn't open a shell (the shell=20
window remains totally empty) and trying to ssh into the system fails=20
with "PTY allocation request failed on channel 0", logging in via a=20
real tty and creating a new pbuilder chroot from there succeeds.

Regards
	Stefan Lippers-Hollmann

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