linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: Scott Wood <scottwood@freescale.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: kumar.gala@freescale.com, linux-kernel@vger.kernel.org,
	linuxppc-dev@ozlabs.org, amit.shah@redhat.com,
	Andrew Morton <akpm@linux-foundation.org>,
	Timur Tabi <timur@freescale.com>
Subject: Re: [PATCH] hvc_console: fix dropping of characters when output byte channel is full
Date: Tue, 14 Sep 2010 15:05:39 -0500	[thread overview]
Message-ID: <20100914150539.45c0672e@schlenkerla.am.freescale.net> (raw)
In-Reply-To: <20100914204410.71942cdc@lxorguk.ukuu.org.uk>

On Tue, 14 Sep 2010 20:44:10 +0100
Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:

> > Yes, hvc_push() reschedules.  It doesn't sit in a tight loop burning
> > electrons!
> > 
> > Can we do something safer&smarter here?
> 
> 
> Its a printk handler - better to lose the bytes than hang the box. I
> think the current code is probably right.

Losing the bytes is unacceptable.  Even if an hvc backend erroneously
returns zero on a permanent error, the timeout should prevent hanging
the box for too long.

Though I suspect the right answer for us may be "don't use the hvc
layer".

-Scott

      parent reply	other threads:[~2010-09-14 20:05 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-08-20 18:45 [PATCH] hvc_console: fix dropping of characters when output byte channel is full Timur Tabi
2010-09-14 16:05 ` Timur Tabi
2010-09-14 19:17 ` Andrew Morton
2010-09-14 19:22   ` Scott Wood
2010-09-14 19:44   ` Alan Cox
2010-09-14 19:25     ` Timur Tabi
2010-09-14 19:52       ` Alan Cox
2010-09-14 19:44         ` Timur Tabi
2010-09-14 20:05     ` Scott Wood [this message]

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=20100914150539.45c0672e@schlenkerla.am.freescale.net \
    --to=scottwood@freescale.com \
    --cc=akpm@linux-foundation.org \
    --cc=alan@lxorguk.ukuu.org.uk \
    --cc=amit.shah@redhat.com \
    --cc=kumar.gala@freescale.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@ozlabs.org \
    --cc=timur@freescale.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).