From: Linus Torvalds <torvalds@osdl.org>
To: Robin Holt <holt@sgi.com>, Andrew Morton <akpm@osdl.org>
Cc: Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] AB-BA deadlock between uidhash_lock and tasklist_lock.
Date: Thu, 10 Mar 2005 10:40:25 -0800 (PST) [thread overview]
Message-ID: <Pine.LNX.4.58.0503101034400.2530@ppc970.osdl.org> (raw)
In-Reply-To: <20050310123714.GA22068@attica.americas.sgi.com>
On Thu, 10 Mar 2005, Robin Holt wrote:
>
> reparent_to_init() does write_lock_irq(&tasklist_lock) then calls
> switch_uid() which calls free_uid() which grabs the uidhash_lock.
>
> Independent of that, we have seen a different cpu call free_uid as a
> result of sys_wait4 and, immediately after acquiring the uidhash_lock,
> receive a timer interrupt which eventually leads to an attempt to grab
> the tasklist_lock.
Hmm.. We fixed this already, and the current tree doesn't have this
problem (and the fix was much simpler: just move "switch_uid()" to outside
the tasklist_lock.
That fix was done late december last year (current BK revision:
1.1938.446.38), and I really think your patch is stale. Please
double-check,
Linus
next prev parent reply other threads:[~2005-03-10 18:55 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-03-10 12:37 Robin Holt
2005-03-10 18:40 ` Linus Torvalds [this message]
-- strict thread matches above, loose matches on Subject: below --
2004-12-22 22:08 Robin Holt
2004-12-23 17:37 ` Robin Holt
2004-12-23 22:54 ` Andrew Morton
2004-12-23 23:21 ` Jesper Juhl
2004-12-23 23:30 ` Andrew Morton
2004-12-23 23:37 ` Linus Torvalds
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=Pine.LNX.4.58.0503101034400.2530@ppc970.osdl.org \
--to=torvalds@osdl.org \
--cc=akpm@osdl.org \
--cc=holt@sgi.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
all inboxes | Powered by JetHome®