From: Larry Finger <Larry.Finger@lwfinger.net>
To: netdev@vger.kernel.org, John Linville <linville@tuxdriver.com>
Subject: Possible circular locking in dev_queue_xmit
Date: Tue, 08 Aug 2006 20:40:24 -0500 [thread overview]
Message-ID: <44D93D08.2010000@lwfinger.net> (raw)
Using the bcm43xx-d80211 driver/stack combination, my system will usually lock
if the interface is plugged in while booting. On one occasion, it was able to
boot with the following message in my logs. This was run with a non-premptible
unit-processor x86 system. If you need further details, please let me know.
=======================================================
kernel: [ INFO: possible circular locking dependency detected ]
kernel: -------------------------------------------------------
kernel: dhcpcd/4627 is trying to acquire lock:
kernel: (&dev->queue_lock){-+..}, at: [<c02c0a86>] dev_queue_xmit+0x56/0x290
kernel:
kernel: but task is already holding lock:
kernel: (&dev->_xmit_lock){-+..}, at: [<c02c0c56>] dev_queue_xmit+0x226/0x290
larrylap kernel:
larrylap kernel: which lock already depends on the new lock.
kernel:
kernel:
kernel: the existing dependency chain (in reverse order) is:
kernel:
kernel: -> #1 (&dev->_xmit_lock){-+..}:
kernel: [<c01335cb>] lock_acquire+0x5b/0x80
kernel: [<c03114b0>] _spin_lock_bh+0x40/0x50
kernel: [<c02cc87c>] dev_activate+0x6c/0x130
kernel: [<c02bf11b>] dev_open+0x6b/0x90
kernel: [<e496812d>] ieee80211_open+0x18d/0x360 [80211]
kernel: [<c02bf0f3>] dev_open+0x43/0x90
kernel: [<c02be0a5>] dev_change_flags+0x55/0x130
kernel: [<c02fd2df>] devinet_ioctl+0x65f/0x6d0
kernel: [<c02fd648>] inet_ioctl+0x88/0xb0
kernel: [<c02b32fb>] sock_ioctl+0xbb/0x260
kernel: [<c017182b>] do_ioctl+0x2b/0x80
kernel: [<c01718d1>] vfs_ioctl+0x51/0x290
kernel: [<c0171b51>] sys_ioctl+0x41/0x60
kernel: [<c0103005>] sysenter_past_esp+0x56/0x8d
kernel:
kernel: -> #0 (&dev->queue_lock){-+..}:
kernel: [<c01335cb>] lock_acquire+0x5b/0x80
kernel: [<c031145b>] _spin_lock+0x3b/0x50
kernel: [<c02c0a86>] dev_queue_xmit+0x56/0x290
kernel: [<e49671af>] ieee80211_subif_start_xmit+0x2df/0x540 [80211]
kernel: [<c02c0932>] dev_hard_start_xmit+0x142/0x240
kernel: [<c02c0c74>] dev_queue_xmit+0x244/0x290
kernel: [<c030cd25>] packet_sendmsg_spkt+0x1c5/0x200
kernel: [<c02b497a>] sock_sendmsg+0xda/0x110
kernel: [<c02b4ce3>] sys_sendto+0xd3/0x100
kernel: [<c02b5382>] sys_socketcall+0x192/0x260
kernel: [<c0103005>] sysenter_past_esp+0x56/0x8d
kernel:
kernel: other info that might help us debug this:
kernel:
kernel: 1 lock held by dhcpcd/4627:
kernel: #0: (&dev->_xmit_lock){-+..}, at: [<c02c0c56>] dev_queue_xmit+0x226/0x290
kernel:
kernel: stack backtrace:
kernel: [<c0103b67>] show_trace_log_lvl+0x197/0x1c0
kernel: [<c0104f7b>] show_trace+0x1b/0x20
kernel: [<c0104fa6>] dump_stack+0x26/0x30
kernel: [<c01312f1>] print_circular_bug_tail+0x61/0x70
kernel: [<c0133020>] __lock_acquire+0xae0/0xd60
kernel: [<c01335cb>] lock_acquire+0x5b/0x80
kernel: [<c031145b>] _spin_lock+0x3b/0x50
kernel: [<c02c0a86>] dev_queue_xmit+0x56/0x290
kernel: [<e49671af>] ieee80211_subif_start_xmit+0x2df/0x540 [80211]
kernel: [<c02c0932>] dev_hard_start_xmit+0x142/0x240
kernel: [<c02c0c74>] dev_queue_xmit+0x244/0x290
kernel: [<c030cd25>] packet_sendmsg_spkt+0x1c5/0x200
kernel: [<c02b497a>] sock_sendmsg+0xda/0x110
kernel: [<c02b4ce3>] sys_sendto+0xd3/0x100
kernel: [<c02b5382>] sys_socketcall+0x192/0x260
kernel: [<c0103005>] sysenter_past_esp+0x56/0x8d
kernel: [<b7f5a410>] 0xb7f5a410
kernel: [<c0104f7b>] show_trace+0x1b/0x20
kernel: [<c0104fa6>] dump_stack+0x26/0x30
kernel: [<c01312f1>] print_circular_bug_tail+0x61/0x70
kernel: [<c0133020>] __lock_acquire+0xae0/0xd60
kernel: [<c01335cb>] lock_acquire+0x5b/0x80
kernel: [<c031145b>] _spin_lock+0x3b/0x50
kernel: [<c02c0a86>] dev_queue_xmit+0x56/0x290
kernel: [<e49671af>] ieee80211_subif_start_xmit+0x2df/0x540 [80211]
kernel: [<c02c0932>] dev_hard_start_xmit+0x142/0x240
kernel: [<c02c0c74>] dev_queue_xmit+0x244/0x290
kernel: [<c030cd25>] packet_sendmsg_spkt+0x1c5/0x200
kernel: [<c02b497a>] sock_sendmsg+0xda/0x110
kernel: [<c02b4ce3>] sys_sendto+0xd3/0x100
kernel: [<c02b5382>] sys_socketcall+0x192/0x260
kernel: [<c0103005>] sysenter_past_esp+0x56/0x8d
reply other threads:[~2006-08-09 1:40 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=44D93D08.2010000@lwfinger.net \
--to=larry.finger@lwfinger.net \
--cc=linville@tuxdriver.com \
--cc=netdev@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;
as well as URLs for NNTP newsgroup(s).