public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Keith Owens <kaos@ocs.com.au>
To: sekharan@us.ibm.com
Cc: Alan Stern <stern@rowland.harvard.edu>,
	Kernel development list <linux-kernel@vger.kernel.org>
Subject: Re: Notifier chains are unsafe
Date: Fri, 28 Oct 2005 10:48:00 +1000	[thread overview]
Message-ID: <6933.1130460480@ocs3.ocs.com.au> (raw)
In-Reply-To: Your message of "Thu, 27 Oct 2005 16:02:08 MST." <1130454128.3586.268.camel@linuxchandra>

On Thu, 27 Oct 2005 16:02:08 -0700, 
Chandra Seetharaman <sekharan@us.ibm.com> wrote:
>On Thu, 2005-10-27 at 17:21 -0400, Alan Stern wrote:
>> The other problem is that you violated Keith's statement that 
>> notifier_call_chain shouldn't take any locks.  On the other hand, if we
>
>I would interpret Keith's comment like this: callout should not be
>called with any locks held (because that would limit the callouts from
>blocking). 

We should be able to call notifier_call_chain() from any context.  That
includes oops, panic, NMI and other unmaskable machine check events.
If you can call notifier_call_chain() from an unmaskable context then
it follows that the callbacks cannot take any locks.  Locks are not
safe in NMI context.


  reply	other threads:[~2005-10-28  0:48 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-10-24 20:48 Notifier chains are unsafe Alan Stern
2005-10-25 16:59 ` Joe Seigh
2005-10-25 23:30 ` Chandra Seetharaman
2005-10-26 18:46   ` Alan Stern
2005-10-26 19:05     ` Andreas Kleen
2005-10-26 20:40       ` Alan Stern
2005-10-26 21:44         ` Andi Kleen
2005-10-26 23:20           ` Chandra Seetharaman
2005-10-27  1:17             ` Joe Seigh
2005-10-28  1:36               ` Chandra Seetharaman
2005-10-27 14:13           ` Alan Stern
2005-10-26 22:40     ` Chandra Seetharaman
2005-10-27 15:28       ` Alan Stern
2005-10-27 20:43         ` Chandra Seetharaman
2005-10-27 21:21           ` Alan Stern
2005-10-27 23:02             ` Chandra Seetharaman
2005-10-28  0:48               ` Keith Owens [this message]
2005-10-28  1:34                 ` Chandra Seetharaman
2005-10-28 14:23                   ` Alan Stern
2005-10-28 22:15                     ` Chandra Seetharaman
2005-10-29 14:51                       ` Alan Stern
2005-10-31 22:22                         ` Chandra Seetharaman
2005-11-01 15:24                           ` Alan Stern
2005-11-01 20:20                             ` Chandra Seetharaman
2005-11-01 21:20                               ` Alan Stern
2005-11-02  9:50                                 ` Keith Owens
2005-11-02 16:03                                   ` Alan Stern
     [not found]               ` <mailman.1130460600.30060.linux-kernel2news@redhat.com>
2005-10-28  4:35                 ` Pete Zaitcev
2005-10-25 23:43 ` Andi Kleen
2005-10-26  0:01   ` Chandra Seetharaman
2005-10-26 17:11     ` Andreas Kleen
2005-10-27  2:46       ` Herbert Xu
2005-10-29 12:25         ` Joe Seigh
2005-10-26  6:11 ` Keith Owens

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=6933.1130460480@ocs3.ocs.com.au \
    --to=kaos@ocs.com.au \
    --cc=linux-kernel@vger.kernel.org \
    --cc=sekharan@us.ibm.com \
    --cc=stern@rowland.harvard.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