From: Paul Bolle <pebolle@tiscali.nl>
To: Tilman Schmidt <tilman@imap.cc>, Peter Hurley <peter@hurleysoftware.com>
Cc: netdev@vger.kernel.org, David Miller <davem@davemloft.net>,
Hansjoerg Lipp <hjlipp@web.de>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] isdn/gigaset: reset tty->receive_room when attaching ser_gigaset
Date: Tue, 14 Jul 2015 21:01:20 +0200 [thread overview]
Message-ID: <1436900480.2679.47.camel@tiscali.nl> (raw)
In-Reply-To: <55A450A0.4080806@imap.cc>
On di, 2015-07-14 at 01:58 +0200, Tilman Schmidt wrote:
> Am 14.07.2015 um 01:14 schrieb Peter Hurley:
> > That commit didn't cause the problem; it was a bug all along.
>
> Sure. That's why it is correctly fixed in the Gigaset driver.
> But before that commit the bug was never actually triggered.
> So that commit defines the point in the commit history from
> which the fix is needed, and therefore needs to be mentioned
> in order to decide which stable releases will need the fix.
Yes, this seems a classic example of a bugfix that reveals another bug.
So the Fixes: tag, which does sound a bit awkward, really is
appropriate.
For ser-gigaset about the only line discipline change that will be
triggered, in practice, is from N_TTY to N_GIGASET_M101. Until commit
79901317ce80 ("n_tty: Don't flush buffer when closing ldisc") that
change would set receive_room to N_TTY_BUF_SIZE (ie, 4096). This patch
will set receive_room for ser-gigaset to RBUFSIZE/2 (ie, again 4096). So
we're back at the pre v3.10 behavior.
I'm really thankful that Tilman managed to bisect this and subsequently
saw how it could be properly fixed. I hope to forward this patch in a
few weeks so that it might finally be fixed in v4.3.
Applied.
Paul Bolle
next prev parent reply other threads:[~2015-07-14 19:01 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-13 22:37 [PATCH 0/2] Fix long-standing regression in ser_gigaset ISDN driver Tilman Schmidt
2015-07-13 22:37 ` [PATCH 2/2] isdn/gigaset: drop unused ldisc methods Tilman Schmidt
2015-07-14 19:03 ` Paul Bolle
2015-07-13 22:37 ` [PATCH 1/2] isdn/gigaset: reset tty->receive_room when attaching ser_gigaset Tilman Schmidt
2015-07-13 23:14 ` Peter Hurley
2015-07-13 23:58 ` Tilman Schmidt
2015-07-14 19:01 ` Paul Bolle [this message]
2015-07-14 12:50 ` Sergei Shtylyov
2015-07-16 0:25 ` [PATCH 0/2] Fix long-standing regression in ser_gigaset ISDN driver David Miller
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=1436900480.2679.47.camel@tiscali.nl \
--to=pebolle@tiscali.nl \
--cc=davem@davemloft.net \
--cc=hjlipp@web.de \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=peter@hurleysoftware.com \
--cc=tilman@imap.cc \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.