public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: "Petr Vandrovec" <VANDROVE@vc.cvut.cz>
To: Rik van Riel <riel@conectiva.com.br>
Cc: akpm@zip.com.au, <linux-kernel@vger.kernel.org>
Subject: Re: BUG at rmap.c:212
Date: Wed, 31 Jul 2002 15:03:12 +0200	[thread overview]
Message-ID: <AD3C93230E@vcnet.vc.cvut.cz> (raw)

On 31 Jul 02 at 9:49, Rik van Riel wrote:
> On Wed, 31 Jul 2002, Petr Vandrovec wrote:
> 
> >   yesterday I told (in IDE thread) that BUG at rmap.c:212 is probably
> > already fixed by changeset 520. Unfortunately, it is not, I got it again
> > with BK tree. It happened again when 'ntpd' called exit() upon receiving
> > sigterm.
> 
> Line 212 is   'pte_chain_unlock(page);'   right ?
> 
> What configuration are you running ?  SMP ?  PREEMPT ?  What compiler ?

Nope. On my system (2.5.29-changeset548) it is a BUG() call which was
added by akpm in rmap.c revision 1.5, in his 'Add BUG() on a can't-happen
code path in page_remove_rmap()'. It just added #else BUG() branch
to #ifdef DEBUG_RMAP conditional.

Kernel is SMP, non-preempt, running on UP P4. Compiler is 2.95.4 from
Debian sid.

> >   Stack trace:
> >
> >   page_remove_rmap
> >   zap_pte_range
> >   zap_pmd_range
> >   unmap_page_range
> >   exit_mmap
> >   mmput
> >   do_exit
> >   sys_exit
> >   syscall_call
> >
> > If it is not known bug, I'll rebuild kernel with DEBUG_RMAP.
> > Unfortunately it looks like that machine must have uptime > 12hrs to
> > trigger this. Probably updatedb or some other task must be run to try to
> > swap ntpd out?
> 
> It is not a known bug. In fact I've never seen this one before.

Probably because of your code did not do anything special when
'Not found. This should NEVER happen!' code path triggers. Code in
bitkeeper since 27th July complains. I'm now running with DEBUG_RMAP
set, so I'll see next time.
                                                        Petr Vandrovec
                                                        vandrove@vc.cvut.cz
                                                        

             reply	other threads:[~2002-07-31 13:00 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-07-31 13:03 Petr Vandrovec [this message]
2002-07-31 13:11 ` BUG at rmap.c:212 Rik van Riel
  -- strict thread matches above, loose matches on Subject: below --
2002-07-31 14:00 Petr Vandrovec
2002-07-31 17:03 ` Andrew Morton
2002-07-31 10:06 Petr Vandrovec
2002-07-31 12:49 ` Rik van Riel

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=AD3C93230E@vcnet.vc.cvut.cz \
    --to=vandrove@vc.cvut.cz \
    --cc=akpm@zip.com.au \
    --cc=linux-kernel@vger.kernel.org \
    --cc=riel@conectiva.com.br \
    /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