From: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
To: Peter Hurley <peter@hurleysoftware.com>
Cc: Karsten Keil <isdn@linux-pingi.de>, Arnd Bergmann <arnd@arndb.de>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
David Laight <David.Laight@ACULAB.COM>,
"linux-serial@vger.kernel.org" <linux-serial@vger.kernel.org>,
"linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>
Subject: Re: [PATCH tty-next 14/22] tty: Remove tty_wait_until_sent_from_close()
Date: Fri, 10 Oct 2014 09:58:28 +0100 [thread overview]
Message-ID: <20141010095828.1f0de28b@alan.etchedpixels.co.uk> (raw)
In-Reply-To: <5434B5D3.4060308@hurleysoftware.com>
> The point being that holding the tty lock across the _entire_ close
> is equivalent to the current outcome, regardless of O_NONBLOCK.
>
> I'm reluctant to start returning EGAIN for non-blocking tty opens
> because no tty driver does that now, and I don't think userspace will
> deal well with new return codes from tty opens.
I do not know about the non blocking case mattering. The blocking open
does need to wait, when I broke that case before I broke the console
login drivers (mingetty).
Returning EAGAIN would also only work if poll/select did the right thing.
Currently Linux can't support a System5 style ttymon process because of
this limitation, which means, for example, that systemd can't implement a
single thread to manage all console prompts/setup
Alan
next prev parent reply other threads:[~2014-10-10 8:58 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1402924639-5164-1-git-send-email-peter@hurleysoftware.com>
2014-06-16 13:17 ` [PATCH tty-next 14/22] tty: Remove tty_wait_until_sent_from_close() Peter Hurley
2014-06-17 8:00 ` Arnd Bergmann
2014-06-17 8:18 ` David Laight
2014-06-17 10:57 ` Peter Hurley
2014-06-17 11:03 ` David Laight
2014-06-17 11:31 ` Arnd Bergmann
2014-06-17 11:54 ` One Thousand Gnomes
2014-06-17 11:32 ` Peter Hurley
2014-07-09 13:57 ` Peter Hurley
2014-10-08 3:56 ` Peter Hurley
2014-10-10 8:58 ` One Thousand Gnomes [this message]
2014-07-10 23:09 ` Greg Kroah-Hartman
2014-07-11 15:03 ` Peter Hurley
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20141010095828.1f0de28b@alan.etchedpixels.co.uk \
--to=gnomes@lxorguk.ukuu.org.uk \
--cc=David.Laight@ACULAB.COM \
--cc=arnd@arndb.de \
--cc=gregkh@linuxfoundation.org \
--cc=isdn@linux-pingi.de \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-serial@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=peter@hurleysoftware.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).