public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Al Viro <viro@ftp.linux.org.uk>
To: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Andrew Morton <akpm@osdl.org>,
	linux-kernel@vger.kernel.org,
	Andreas Herrmann <aherrman@de.ibm.com>
Subject: Re: [PATCH resubmit] do_mount: reduce stack consumption
Date: Fri, 4 Nov 2005 14:06:55 +0000	[thread overview]
Message-ID: <20051104140655.GI7992@ftp.linux.org.uk> (raw)
In-Reply-To: <20051104125705.GB12476@osiris.boeblingen.de.ibm.com>

On Fri, Nov 04, 2005 at 01:57:05PM +0100, Heiko Carstens wrote:
> > > This is a resubmit of Andreas' patch that reduces stackframe usage in
> > > do_mount. Problem is that without this patch we get a kernel stack
> > > overflow if we run with 4k stacks (s390 31 bit mode).
> > > See original stack back trace below and Andreas' patch and analysis
> > > here:
> > > http://www.ussg.iu.edu/hypermail/linux/kernel/0410.3/1844.html
> > 
> > NAK.  Rationale: too ugly.
> 
> Ok, since I can only guess what you don't like: here is an updated patch
> that probably addresses a few things.
> If you don't like this one too, could you please explain what should be
> changed?

Depth analysis.  E.g. do_move_mount() change is simply nonsense - _this_
is not going to overflow, no matter what.  And do_add_mount() change
is also very suspicious - looks like you are attacking the wrong place
in call chain.

  reply	other threads:[~2005-11-04 14:06 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-11-04 10:50 [PATCH resubmit] do_mount: reduce stack consumption Heiko Carstens
2005-11-04 11:48 ` Al Viro
2005-11-04 12:57   ` Heiko Carstens
2005-11-04 14:06     ` Al Viro [this message]
2005-11-04 22:03       ` Heiko Carstens
2005-11-04 16:48 ` Andrew Morton
2005-11-04 21:27   ` Heiko Carstens
2005-11-04 23:55     ` Adrian Bunk
2005-11-05  0:08       ` Andrew Morton
2005-11-05  1:15         ` cplk
2005-11-05  1:37           ` Andrew Morton
2005-11-05  5:37             ` Neil Brown
2005-11-07  0:16               ` [dm-devel] " Neil Brown
2005-11-07 16:15                 ` Heiko Carstens
2005-11-07 22:12                   ` Neil Brown
2005-11-07 23:37                 ` Andrew Morton
2005-11-08  0:32                   ` Nick Piggin
2005-11-08  1:03                     ` Neil Brown
2005-11-08  1:15                       ` Andrew Morton
2005-11-08  1:37                       ` Nick Piggin
  -- strict thread matches above, loose matches on Subject: below --
2005-11-04 15:53 Andreas Herrmann
2005-11-04 17:42 ` Andrew Morton
2005-11-04 17:45   ` Arjan van de Ven
2005-11-04 18:37     ` Andrew Morton

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=20051104140655.GI7992@ftp.linux.org.uk \
    --to=viro@ftp.linux.org.uk \
    --cc=aherrman@de.ibm.com \
    --cc=akpm@osdl.org \
    --cc=heiko.carstens@de.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    /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