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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 1 Jan 2020 15:01:12 -0800
Message-ID: <CAHk-=wgHg8z5WQBoypjyi0VPp3E44oO_Szuvk9f6v1mGMqsSZg@mail.gmail.com>
Subject: Re: [PATCH] early init: open /dev/console with O_LARGEFILE
To:     Arvind Sankar <nivedita@alum.mit.edu>
Cc:     Dominik Brodowski <linux@dominikbrodowski.net>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        youling 257 <youling257@gmail.com>
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On Wed, Jan 1, 2020 at 2:50 PM Arvind Sankar <nivedita@alum.mit.edu> wrote:
>
> Shouldn't that only affect init though? The getty's it spawns should be
> in their own sessions.

They *should* be in their own sessions, and clearly this problem
doesn't seem to really affect much anybody else.

But I think youling has some limited and/or odd init userspace, and I
think it gets confused.

So my theory is that because of the file descriptor leak, that "forget
the old controlling tty" doesn't happen, and then subsequent tty opens
don't do the right thing.

Maybe.

But it's the only real semantic change I can see in that whole patch.

                 Linus