From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [BUG] Hang (deadlock?) inside iscsi_if_rx Date: Tue, 24 Jan 2012 09:30:47 -0500 Message-ID: <1327415447.15015.0.camel@lappy> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Sender: linux-kernel-owner@vger.kernel.org To: michaelc@cs.wisc.edu, JBottomley@parallels.com Cc: Dave Jones , open-iscsi@googlegroups.com, linux-scsi@vger.kernel.org, linux-kernel List-Id: linux-scsi@vger.kernel.org Hi all, I got the following hang when running trinity under KVM tool: [ 2520.824250] INFO: task trinity:31986 blocked for more than 120 seconds. [ 2520.825513] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 2520.826983] trinity D 0000000000000000 5504 31986 2767 0x00000004 [ 2520.828416] ffff88000a21ba98 0000000000000086 ffff88000a3f8000 ffff88000a3f8000 [ 2520.829892] 00000000001d4340 ffff88000a21bfd8 ffff88000a21a000 00000000001d4340 [ 2520.831380] 00000000001d4340 00000000001d4340 ffff88000a21bfd8 00000000001d4340 [ 2520.832838] Call Trace: [ 2520.837089] [] schedule+0x3a/0x50 [ 2520.837983] [] __mutex_lock_common+0x209/0x5b0 [ 2520.839181] [] ? iscsi_if_rx+0x23/0xa00 [ 2520.840232] [] ? sched_clock+0x13/0x20 [ 2520.841242] [] ? iscsi_if_rx+0x23/0xa00 [ 2520.842271] [] mutex_lock_nested+0x40/0x50 [ 2520.843353] [] iscsi_if_rx+0x23/0xa00 [ 2520.844461] [] ? sub_preempt_count+0x9d/0xd0 [ 2520.845576] [] ? _raw_read_unlock+0x30/0x60 [ 2520.846705] [] netlink_unicast+0x1ae/0x1f0 [ 2520.847790] [] netlink_sendmsg+0x227/0x350 [ 2520.848884] [] ? sock_update_netprioidx+0xdd/0x1b0 [ 2520.850105] [] ? sock_update_netprioidx+0x52/0x1b0 [ 2520.851282] [] sock_aio_write+0x166/0x180 [ 2520.852317] [] ? get_parent_ip+0x11/0x50 [ 2520.853342] [] do_sync_write+0xda/0x120 [ 2520.854347] [] ? lock_release_holdtime+0xb2/0x160 [ 2520.855533] [] ? get_parent_ip+0x11/0x50 [ 2520.856569] [] ? security_file_permission+0x27/0xb0 [ 2520.857756] [] vfs_write+0x16c/0x180 [ 2520.858713] [] sys_write+0x4f/0xa0 [ 2520.859680] [] system_call_fastpath+0x16/0x1b [ 2520.873039] 1 lock held by trinity/31986: [ 2520.873801] #0: (rx_queue_mutex){+.+...}, at: [] iscsi_if_rx+0x23/0xa00 [ 2520.875587] Kernel panic - not syncing: hung_task: blocked tasks >>From looking at the logs, there were two instances of the fuzzer blocked on a write() to a netlink socket. There are no iSCSI targets anywhere on the network. Thanks. -- Sasha.