public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Russell King <rmk@arm.linux.org.uk>
To: jt@hpl.hp.com
Cc: Linux kernel mailing list <linux-kernel@vger.kernel.org>,
	Alan Cox <alan@lxorguk.ukuu.org.uk>,
	tytso@mit.edu, Andrew Morton <andrewm@uow.edu.eu>,
	irda-users@lists.sourceforge.net
Subject: Re: [BUG/PATCH] : bug in tty_default_put_char()
Date: Mon, 26 Aug 2002 20:31:26 +0100	[thread overview]
Message-ID: <20020826203126.C4763@flint.arm.linux.org.uk> (raw)
In-Reply-To: <20020826180749.GA8630@bougret.hpl.hp.com>; from jt@bougret.hpl.hp.com on Mon, Aug 26, 2002 at 11:07:49AM -0700

On Mon, Aug 26, 2002 at 11:07:49AM -0700, Jean Tourrilhes wrote:
> 	Bug : tty_default_put_char() doesn't check the return value of
> tty->driver.write(). However, the later may fail if buffers are full.

Hmm.

> 	Solution : It's not obvious what should be done. The attached
> patch is certainly wrong, but gives you an idea of what the problem
> is.

Every invocation of the put_char() method should be preceded by a check
to ensure that there is sufficient space in the drivers buffer (via the
drivers write_room() call.)  Could you add a BUG() on this condition
and get some call traces please?

> 	I'll try to workaround that in IrCOMM.

I don't think that should be necessary.  The tty layer is obviously
doing something it shouldn't (trying to stuff characters into a buffer
of zero size) so it should get fixed.

-- 
Russell King (rmk@arm.linux.org.uk)                The developer of ARM Linux
             http://www.arm.linux.org.uk/personal/aboutme.html


  parent reply	other threads:[~2002-08-26 19:27 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-08-26 18:07 [BUG/PATCH] : bug in tty_default_put_char() Jean Tourrilhes
     [not found] ` <1030388224.2797.2.camel@irongate.swansea.linux.org.uk>
2002-08-26 18:59   ` Jean Tourrilhes
2002-08-26 19:07     ` Alan Cox
2002-08-26 20:17       ` Russell King
2002-08-26 19:31 ` Russell King [this message]
     [not found]   ` <20020826195346.GC8749@bougret.hpl.hp.com>
     [not found]     ` <20020826210159.E4763@flint.arm.linux.org.uk>
     [not found]       ` <20020826201732.GE8749@bougret.hpl.hp.com>
     [not found]         ` <20020826212223.H4763@flint.arm.linux.org.uk>
2002-08-28 22:41           ` Jean Tourrilhes
2002-08-28 23:16             ` Russell King

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=20020826203126.C4763@flint.arm.linux.org.uk \
    --to=rmk@arm.linux.org.uk \
    --cc=alan@lxorguk.ukuu.org.uk \
    --cc=andrewm@uow.edu.eu \
    --cc=irda-users@lists.sourceforge.net \
    --cc=jt@hpl.hp.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tytso@mit.edu \
    /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