From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757238AbZGMUy6 (ORCPT ); Mon, 13 Jul 2009 16:54:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756812AbZGMUy5 (ORCPT ); Mon, 13 Jul 2009 16:54:57 -0400 Received: from turing-police.cc.vt.edu ([128.173.14.107]:57122 "EHLO turing-police.cc.vt.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756769AbZGMUy4 (ORCPT ); Mon, 13 Jul 2009 16:54:56 -0400 X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.2 To: linux-kernel@vger.kernel.org, Andrew Morton Subject: 2.6.31-rc1-mmotm0702 - ps command hangs inside kernel From: Valdis.Kletnieks@vt.edu Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1247518491_4148P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Mon, 13 Jul 2009 16:54:51 -0400 Message-ID: <47423.1247518491@turing-police.cc.vt.edu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --==_Exmh_1247518491_4148P Content-Type: text/plain; charset="us-ascii" Content-Id: <47416.1247518491.1@turing-police.cc.vt.edu> Several times recently, I've had the 'ps' command hang inside the kernel for extended periods of time - usually around 1100 seconds, but today I had one that hung there for 2351 seconds. Info: It's always reading the same file - /proc//status, where the pid is the 'pcscd' daemon. And eventually, it manages to exit on its own. Whatever is getting horked up resets itself - subsequent 'ps' commands work just fine. My best guess is that it's getting onto a squirrely vma in get_stack_usage_in_bytes() in the for/follow_page loop. Possibly highly relevant - /usr/sbin/pcscd is one of the few 32-bit binaries running in a mostly 64-bit runtime. Here's the traceback of the ps, as reported by 2 alt-sysrq-t several minutes apart: ps R running task 3936 26646 26580 0x00000080 ffff88005a599be8 ffffffff81499842 ffff88005a599b78 ffffffff8103589b ffffffff81035805 ffff88007e71ea40 ffff880002120f80 ffff8800657d8fe0 000000000000df78 ffff8800657d8fe0 000000000000df78 ffff8800657d8fe8 Call Trace: [] ? thread_return+0xb6/0xfa [] ? finish_task_switch+0xd1/0xf4 [] ? finish_task_switch+0x3b/0xf4 [] ? trace_hardirqs_on_caller+0x1f/0x145 [] ? trace_hardirqs_on_thunk+0x3a/0x3f [] ? smp_apic_timer_interrupt+0x81/0x8f [] ? irq_exit+0xaf/0xb4 [] restore_args+0x0/0x30 [] ? trace_hardirqs_on_caller+0x1f/0x145 [] ? trace_hardirqs_on_thunk+0x3a/0x3f [] ? smp_apic_timer_interrupt+0x81/0x8f [] ? IS_ERR+0x25/0x2c [] ? follow_page+0x28/0x2e3 [] ? proc_pid_status+0x60c/0x694 [] ? trace_hardirqs_on+0xd/0xf [] ? proc_single_show+0x57/0x74 [] ? seq_read+0x249/0x49b [] ? security_file_permission+0x11/0x13 [] ? vfs_read+0xe0/0x141 [] ? path_put+0x1d/0x21 [] ? sys_read+0x45/0x69 [] ? system_call_fastpath+0x16/0x1b ps R running task 3936 26646 26580 0x00000080 ffff88005a599bd8 ffffffff81499842 ffff88000213bf80 0000000000000000 ffff88005a599b78 ffffffff8103589b ffffffff81035805 ffff88007e71ea40 ffff88000213bf80 ffff8800657d8fe0 000000000000df78 ffff8800657d8fe8 Call Trace: [] ? thread_return+0xb6/0xfa [] ? finish_task_switch+0xd1/0xf4 [] ? finish_task_switch+0x3b/0xf4 [] ? trace_hardirqs_on_caller+0x1f/0x145 [] ? trace_hardirqs_on_thunk+0x3a/0x3f [] smp_apic_timer_interrupt+0x81/0x8f [] ? irq_exit+0xaf/0xb4 [] ? restore_args+0x0/0x30 [] ? IS_ERR+0x25/0x2c [] ? IS_ERR+0x25/0x2c [] ? follow_page+0x28/0x2e3 [] ? follow_page+0x2df/0x2e3 [] ? proc_pid_status+0x5e0/0x694 [] ? trace_hardirqs_on+0xd/0xf [] ? proc_single_show+0x57/0x74 [] ? seq_read+0x249/0x49b [] ? security_file_permission+0x11/0x13 [] ? vfs_read+0xe0/0x141 [] ? path_put+0x1d/0x21 [] ? sys_read+0x45/0x69 [] ? system_call_fastpath+0x16/0x1b Here's the output of 'cat /proc/2031/maps' currently - I didn't think to get one during the last event: # cat /proc/2031/maps 08047000-0805e000 r-xp 00000000 fe:05 51682 /usr/sbin/pcscd 0805e000-0805f000 rw-p 00016000 fe:05 51682 /usr/sbin/pcscd 0805f000-080e8000 rw-p 00000000 00:00 0 09990000-099b1000 rw-p 00000000 00:00 0 [heap] 44368000-4436f000 r-xp 00000000 fe:05 20682 /usr/lib/libusb-0.1.so.4.4.4 4436f000-44371000 rw-p 00006000 fe:05 20682 /usr/lib/libusb-0.1.so.4.4.4 45c81000-45cab000 r-xp 00000000 fe:00 8715 /lib/libgcc_s-4.4.0-20090708.so.1 45cab000-45cac000 rw-p 0002a000 fe:00 8715 /lib/libgcc_s-4.4.0-20090708.so.1 47c00000-47c20000 r-xp 00000000 fe:00 8266 /lib/ld-2.10.1.so 47c20000-47c21000 r--p 0001f000 fe:00 8266 /lib/ld-2.10.1.so 47c21000-47c22000 rw-p 00020000 fe:00 8266 /lib/ld-2.10.1.so 47c24000-47d8f000 r-xp 00000000 fe:00 8360 /lib/libc-2.10.1.so 47d8f000-47d90000 ---p 0016b000 fe:00 8360 /lib/libc-2.10.1.so 47d90000-47d92000 r--p 0016b000 fe:00 8360 /lib/libc-2.10.1.so 47d92000-47d93000 rw-p 0016d000 fe:00 8360 /lib/libc-2.10.1.so 47d93000-47d96000 rw-p 00000000 00:00 0 47d98000-47d9b000 r-xp 00000000 fe:00 8388 /lib/libdl-2.10.1.so 47d9b000-47d9c000 r--p 00002000 fe:00 8388 /lib/libdl-2.10.1.so 47d9c000-47d9d000 rw-p 00003000 fe:00 8388 /lib/libdl-2.10.1.so 47d9f000-47db5000 r-xp 00000000 fe:00 8675 /lib/libpthread-2.10.1.so 47db5000-47db6000 ---p 00016000 fe:00 8675 /lib/libpthread-2.10.1.so 47db6000-47db7000 r--p 00016000 fe:00 8675 /lib/libpthread-2.10.1.so 47db7000-47db8000 rw-p 00017000 fe:00 8675 /lib/libpthread-2.10.1.so 47db8000-47dba000 rw-p 00000000 00:00 0 f6c00000-f6c21000 rw-p 00000000 00:00 0 f6c21000-f6d00000 ---p 00000000 00:00 0 f6dff000-f6e00000 ---p 00000000 00:00 0 f6e00000-f7600000 rw-p 00000000 00:00 0 f7600000-f7621000 rw-p 00000000 00:00 0 f7621000-f7700000 ---p 00000000 00:00 0 f773b000-f773c000 ---p 00000000 00:00 0 f773c000-f7f3f000 rw-p 00000000 00:00 0 f7f50000-f7f51000 rw-s 0000f000 fe:09 86049 /var/run/pcscd.pub f7f51000-f7f52000 rw-s 0000e000 fe:09 86049 /var/run/pcscd.pub f7f52000-f7f53000 rw-s 0000d000 fe:09 86049 /var/run/pcscd.pub f7f53000-f7f54000 rw-s 0000c000 fe:09 86049 /var/run/pcscd.pub f7f54000-f7f55000 rw-s 0000b000 fe:09 86049 /var/run/pcscd.pub f7f55000-f7f56000 rw-s 0000a000 fe:09 86049 /var/run/pcscd.pub f7f56000-f7f57000 rw-s 00009000 fe:09 86049 /var/run/pcscd.pub f7f57000-f7f58000 rw-s 00008000 fe:09 86049 /var/run/pcscd.pub f7f58000-f7f59000 rw-s 00007000 fe:09 86049 /var/run/pcscd.pub f7f59000-f7f5a000 rw-s 00006000 fe:09 86049 /var/run/pcscd.pub f7f5a000-f7f5b000 rw-s 00005000 fe:09 86049 /var/run/pcscd.pub f7f5b000-f7f5c000 rw-s 00004000 fe:09 86049 /var/run/pcscd.pub f7f5c000-f7f5d000 rw-s 00003000 fe:09 86049 /var/run/pcscd.pub f7f5d000-f7f5e000 rw-s 00002000 fe:09 86049 /var/run/pcscd.pub f7f5e000-f7f5f000 rw-s 00001000 fe:09 86049 /var/run/pcscd.pub f7f5f000-f7f60000 rw-s 00000000 fe:09 86049 /var/run/pcscd.pub f7f60000-f7f61000 r-xp 00000000 00:00 0 [vdso] fffe8000-ffffd000 rw-p 00000000 00:00 0 [stack] --==_Exmh_1247518491_4148P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Exmh version 2.5 07/13/2001 iD8DBQFKW58bcC3lWbTT17ARAq6TAJ9jfdEKd7UfKADPRU8D9bW5Qm49wQCg7zy0 QTX9X5nqifBHT+hj+AjS5rk= =wfdo -----END PGP SIGNATURE----- --==_Exmh_1247518491_4148P--