From: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-kernel@vger.kernel.org
Subject: tty locking problem (possible recursive locking detected)
Date: Tue, 29 May 2012 00:13:00 +0200 [thread overview]
Message-ID: <20120528221300.GD16584@smp.if.uj.edu.pl> (raw)
Hi,
I just compiled recent Linus tree and this is what I got after opening terminator terminal:
[ 7608.413277]
[ 7608.413287] =============================================
[ 7608.413289] [ INFO: possible recursive locking detected ]
[ 7608.413293] 3.4.0-t43-devel-smp-08215-g1e2aec8-dirty #6 Not tainted
[ 7608.413296] ---------------------------------------------
[ 7608.413298] bash/13259 is trying to acquire lock:
[ 7608.413313] (&tty->legacy_mutex){+.+.+.}, at: [<c17c3daf>] tty_lock+0x2f/0x70
[ 7608.413315]
[ 7608.413315] but task is already holding lock:
[ 7608.413322] (&tty->legacy_mutex){+.+.+.}, at: [<c17c3daf>] tty_lock+0x2f/0x70
[ 7608.413324]
[ 7608.413324] other info that might help us debug this:
[ 7608.413327] Possible unsafe locking scenario:
[ 7608.413327]
[ 7608.413330] CPU0
[ 7608.413331] ----
[ 7608.413335] lock(&tty->legacy_mutex);
[ 7608.413339] lock(&tty->legacy_mutex);
[ 7608.413341]
[ 7608.413341] *** DEADLOCK ***
[ 7608.413341]
[ 7608.413344] May be due to missing lock nesting notation
[ 7608.413344]
[ 7608.413347] 2 locks held by bash/13259:
[ 7608.413356] #0: (tty_mutex){+.+.+.}, at: [<c13d3405>] tty_release+0x145/0x4f0
[ 7608.413364] #1: (&tty->legacy_mutex){+.+.+.}, at: [<c17c3daf>] tty_lock+0x2f/0x70
[ 7608.413366]
[ 7608.413366] stack backtrace:
[ 7608.413370] Pid: 13259, comm: bash Not tainted 3.4.0-t43-devel-smp-08215-g1e2aec8-dirty #6
[ 7608.413373] Call Trace:
[ 7608.413379] [<c10b8945>] __lock_acquire+0x1535/0x1760
[ 7608.413386] [<c10b0008>] ? clockevents_program_event+0xc8/0x160
[ 7608.413391] [<c101d2d8>] ? sched_clock+0x8/0x10
[ 7608.413397] [<c1080413>] ? set_groups+0xd3/0x170
[ 7608.413402] [<c10b91a9>] lock_acquire+0x89/0x1b0
[ 7608.413406] [<c17c3daf>] ? tty_lock+0x2f/0x70
[ 7608.413413] [<c17c02d0>] mutex_lock_nested+0x70/0x300
[ 7608.413417] [<c17c3daf>] ? tty_lock+0x2f/0x70
[ 7608.413421] [<c17c3daf>] ? tty_lock+0x2f/0x70
[ 7608.413425] [<c17c3daf>] tty_lock+0x2f/0x70
[ 7608.413429] [<c17c3e0d>] tty_lock_pair+0x1d/0x56
[ 7608.413433] [<c13d340e>] tty_release+0x14e/0x4f0
[ 7608.413440] [<c118f5ec>] fput+0xfc/0x230
[ 7608.413444] [<c10b413c>] ? lock_release_holdtime.part.20+0xcc/0xf0
[ 7608.413450] [<c118a792>] filp_close+0x52/0x80
[ 7608.413454] [<c118b0ea>] sys_close+0x8a/0x160
[ 7608.413460] [<c17cb998>] sysenter_do_call+0x12/0x38
I belive this is releated to recent tty and tty lock changes:
commit 94b5aff4c6f72fee6b0f49d49e4fa8b204e8ded9
Merge: 5d4e2d0 59bd234
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date: Tue May 22 16:12:24 2012 -0700
Merge tag 'tty-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
This is 32-bit Intel system (i386), with gcc 4.7.0-9 from Debian sid.
Regards,
Witek
--
Witold Baryluk
next reply other threads:[~2012-05-28 22:18 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-28 22:13 Witold Baryluk [this message]
2012-05-28 23:33 ` Alan Cox
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=20120528221300.GD16584@smp.if.uj.edu.pl \
--to=baryluk@smp.if.uj.edu.pl \
--cc=gregkh@linuxfoundation.org \
--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®