All of lore.kernel.org
 help / color / mirror / Atom feed
From: Aaron Straus <aaron@merfinllc.com>
To: netdev@vger.kernel.org
Subject: Lockdep traceback under heavy load
Date: Mon, 20 Nov 2006 11:52:36 -0800	[thread overview]
Message-ID: <20061120195236.GE25908@hydra> (raw)

Hi,

  I got a lockdep traceback recently.  The machine is a i386 dell
inspiron 700m running 2.6.19-rc6.  I was putting NFS through a workout
at the time.

This was the mount I was putting through a workout:

mamba:/export/data on /mnt/merfin/data type nfs
(ro,rsize=8192,wsize=8192,hard,intr,addr=...)

firefox was using a different mount to a different machine. 

  I sent this to Trond originally who suggested sending it to netdev.

  If you want any more information, let me know.

				Regards,
				=aaron=

Here is the traceback:

=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.19-rc6-asb #8
-------------------------------------------------------
firefox-bin/6488 is trying to acquire lock:
 (&mm->mmap_sem){----}, at: [<c0112d71>] do_page_fault+0x19f/0x562

but task is already holding lock:
 (sk_lock-AF_INET){--..}, at: [<c0298f90>] tcp_recvmsg+0x13/0x6fb

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (sk_lock-AF_INET){--..}:
       [<c012f75f>] add_lock_to_list+0x62/0x7e
       [<c013002c>] __lock_acquire+0x8b1/0x9a9
       [<c01303e2>] lock_acquire+0x5a/0x78
       [<c027288e>] lock_sock+0xce/0xdb
       [<c02ac2b7>] udp_sendmsg+0x36c/0x517
       [<c02b2b60>] inet_sendmsg+0x45/0x4f
       [<c0271cdf>] sock_sendmsg+0xda/0xf2
       [<c0272061>] kernel_sendmsg+0x3d/0x4e
       [<f8b7bfc9>] xs_udp_send_request+0x10d/0x295 [sunrpc]
       [<f8b7a53a>] xprt_transmit+0xd5/0x1d5 [sunrpc]
       [<f8b78e8e>] call_transmit+0x1d0/0x1fe [sunrpc]
       [<f8b7e0b3>] __rpc_execute+0x89/0x1be [sunrpc]
       [<f8b7e1fd>] rpc_execute+0x15/0x17 [sunrpc]
       [<f8bfef7e>] nfs_execute_read+0x3f/0x58 [nfs]
       [<f8bff7c3>] nfs_pagein_one+0x212/0x22a [nfs]
       [<f8bff941>] nfs_readpages+0x166/0x1d6 [nfs]
       [<c0142b51>] __do_page_cache_readahead+0x14b/0x20f
       [<c0142d22>] do_page_cache_readahead+0x48/0x51
       [<c013e7c0>] filemap_nopage+0x1a2/0x3ad
       [<c0148a65>] __handle_mm_fault+0x148/0x847
       [<c0112e11>] do_page_fault+0x23f/0x562
       [<c02cd101>] error_code+0x39/0x40
       [<ffffffff>] 0xffffffff

-> #0 (&mm->mmap_sem){----}:
       [<c012f6c7>] print_circular_bug_tail+0x30/0x66
       [<c012ff2b>] __lock_acquire+0x7b0/0x9a9
       [<c01303e2>] lock_acquire+0x5a/0x78
       [<c012c258>] down_read+0x50/0x61
       [<c0112d71>] do_page_fault+0x19f/0x562
       [<c02cd101>] error_code+0x39/0x40
       [<c01c6f4a>] copy_to_user+0x58/0x66
       [<c0277777>] memcpy_toiovec+0x34/0x5a
       [<c0277f71>] skb_copy_datagram_iovec+0x4d/0x1c1
       [<c02993ce>] tcp_recvmsg+0x451/0x6fb
       [<c0272a71>] sock_common_recvmsg+0x4d/0x62
       [<c0272157>] sock_recvmsg+0xe5/0xfe
       [<c02723d4>] sys_recvfrom+0x9d/0xec
       [<c0272459>] sys_recv+0x36/0x38
       [<c02725d3>] sys_socketcall+0x178/0x22d
       [<c0102eed>] sysenter_past_esp+0x56/0x8d
       [<ffffffff>] 0xffffffff

other info that might help us debug this:

1 lock held by firefox-bin/6488:
 #0:  (sk_lock-AF_INET){--..}, at: [<c0298f90>] tcp_recvmsg+0x13/0x6fb

stack backtrace:
 [<c0103f18>] dump_trace+0x76/0x1ed
 [<c01040b5>] show_trace_log_lvl+0x26/0x3c
 [<c010441e>] show_trace+0x19/0x1b
 [<c0104446>] dump_stack+0x26/0x28
 [<c012f6f4>] print_circular_bug_tail+0x5d/0x66
 [<c012ff2b>] __lock_acquire+0x7b0/0x9a9
 [<c01303e2>] lock_acquire+0x5a/0x78
 [<c012c258>] down_read+0x50/0x61
 [<c0112d71>] do_page_fault+0x19f/0x562
 [<c02cd101>] error_code+0x39/0x40
DWARF2 unwinder stuck at error_code+0x39/0x40

Leftover inexact backtrace:

 [<c01c6f4a>] copy_to_user+0x58/0x66
 [<c0277777>] memcpy_toiovec+0x34/0x5a
 [<c0277f71>] skb_copy_datagram_iovec+0x4d/0x1c1
 [<c02993ce>] tcp_recvmsg+0x451/0x6fb
 [<c0272a71>] sock_common_recvmsg+0x4d/0x62
 [<c0272157>] sock_recvmsg+0xe5/0xfe
 [<c02723d4>] sys_recvfrom+0x9d/0xec
 [<c0272459>] sys_recv+0x36/0x38
 [<c02725d3>] sys_socketcall+0x178/0x22d
 [<c0102eed>] sysenter_past_esp+0x56/0x8d
 =======================

-- 
===================
Aaron Straus
aaron@merfinllc.com

                 reply	other threads:[~2006-11-20 19:52 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=20061120195236.GE25908@hydra \
    --to=aaron@merfinllc.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 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.