From: Brian King <brking@us.ibm.com>
To: linux-kernel@vger.kernel.org
Subject: call_usermodehelper hang
Date: Tue, 06 Apr 2004 13:11:03 -0500 [thread overview]
Message-ID: <4072F2B7.2070605@us.ibm.com> (raw)
I have been running into some kernel hangs due to call_usermodehelper. Looking
at the backtrace, it looks to me like there are deadlock issues with adding
devices from work queues. Attached is a sample backtrace from one of the
hangs I experienced. My question is why does call_usermodehelper do 2 different
things depending on whether or not it is called from the kevent task? It appears
that the simple way to fix the hang would be to never have call_usermodehelper
use a work_queue since it must be called from process context anyway, or
am I missing something?
0xc0000000017df300 1 0 0 0 D 0xc0000000017df7b0 swapper
SP(esp) PC(eip) Function(args)
0xc00000003fc9f460 0x0000000000000000 NO_SYMBOL or Userspace
0xc00000003fc9f4f0 0xc000000000058c40 .schedule +0xb4
0xc00000003fc9f5c0 0xc00000000005a464 .wait_for_completion +0x138
0xc00000003fc9f6c0 0xc00000000007c594 .call_usermodehelper +0x104
0xc00000003fc9f810 0xc00000000022d3e8 .kobject_hotplug +0x3c4
0xc00000003fc9f900 0xc00000000022d67c .kobject_add +0x134
0xc00000003fc9f9a0 0xc00000000012b3d8 .register_disk +0x70
0xc00000003fc9fa40 0xc00000000027dfe4 .add_disk +0x60
0xc00000003fc9fad0 0xc0000000002dc7dc .sd_probe +0x290
0xc00000003fc9fb80 0xc00000000026fbe8 .bus_match +0x94
0xc00000003fc9fc10 0xc00000000026ff70 .driver_attach +0x8c
0xc00000003fc9fca0 0xc000000000270104 .bus_add_driver +0x110
0xc00000003fc9fd50 0xc000000000270a18 .driver_register +0x38
0xc00000003fc9fdd0 0xc0000000002cd8f8 .scsi_register_driver +0x28
0xc00000003fc9fe50 0xc0000000004941d8 .init_sd +0x8c
0xc00000003fc9fee0 0xc00000000000c720 .init +0x25c
0xc00000003fc9ff90 0xc0000000000183ec .kernel_thread +0x4c
0xc00000003fab3380 4 1 0 0 D 0xc00000003fab3830 events/0
SP(esp) PC(eip) Function(args)
0xc00000003faaf6e0 0x0000000000000000 NO_SYMBOL or Userspace
0xc00000003faaf770 0xc000000000058c40 .schedule +0xb4
0xc00000003faaf840 0xc00000000022fa20 .rwsem_down_write_failed +0x14c
0xc00000003faaf910 0xc00000000026fed0 .bus_add_device +0x11c
0xc00000003faaf9b0 0xc00000000026e288 .device_add +0xd0
0xc00000003faafa50 0xc0000000002cdb00 .scsi_sysfs_add_sdev +0x8c
0xc00000003faafb00 0xc0000000002cbff8 .scsi_probe_and_add_lun +0xb04
0xc00000003faafc00 0xc0000000002ccca0 .scsi_add_device +0x90
0xc00000003faafcb0 0xc0000000002d9458 .ipr_worker_thread +0xc60
0xc00000003faafdc0 0xc00000000007cd9c .worker_thread +0x268
0xc00000003faafee0 0xc0000000000839cc .kthread +0x160
0xc00000003faaff90 0xc0000000000183ec .kernel_thread +0x4c
--
Brian King
eServer Storage I/O
IBM Linux Technology Center
--
Brian King
eServer Storage I/O
IBM Linux Technology Center
next reply other threads:[~2004-04-06 18:11 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-04-06 18:11 Brian King [this message]
2004-04-07 0:29 ` call_usermodehelper hang Andrew Morton
2004-04-07 6:11 ` Greg KH
2004-04-07 14:00 ` Brian King
2004-04-07 22:58 ` [PATCH] " Brian King
2004-04-08 22:47 ` Greg KH
2004-04-08 22:47 ` Greg KH
2004-04-09 20:42 ` Brian King
2004-04-09 20:42 ` Brian King
2004-04-09 20:53 ` Greg KH
2004-04-09 20:53 ` Greg KH
2004-04-09 21:05 ` Brian King
2004-04-09 21:05 ` Brian King
2004-04-09 21:15 ` Andrew Morton
2004-04-09 21:15 ` Andrew Morton
2004-04-10 16:53 ` Greg KH
2004-04-10 16:53 ` Greg KH
2004-04-10 20:11 ` Andrew Morton
2004-04-10 20:11 ` Andrew Morton
2004-04-12 15:25 ` Brian King
2004-04-12 15:25 ` Brian King
2004-04-12 17:46 ` Andrew Morton
2004-04-12 17:46 ` Andrew Morton
2004-04-16 17:55 ` Brian King
2004-04-16 17:55 ` Brian King
2004-04-12 18:49 ` Greg KH
2004-04-12 18:49 ` Greg KH
2004-04-08 23:17 ` Chris Wright
2004-04-07 0:41 ` Chris Wright
2004-04-07 1:46 ` Brian King
-- strict thread matches above, loose matches on Subject: below --
2005-02-25 17:17 Payasam Manohar
2005-02-25 18:06 ` Lee Revell
2004-04-06 21:58 Brian King
2004-04-06 17:03 Brian King
2004-04-16 8:52 ` Heiko Carstens
2004-04-16 8:52 ` Heiko Carstens
2004-04-16 14:06 ` Brian King
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=4072F2B7.2070605@us.ibm.com \
--to=brking@us.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.