My GFS2 filesystem appears to be hung with the following function in the backtrace on RHEL 5 or RHEL6 "gfs2_flock()"

Issue

• My GFS2 filesystem appears to be hung with the following function in the backtrace on RHEL 5 or RHEL6 gfs2_flock():

Jun  9 12:36:05 node42 kernel: INFO: task dbinstal:36425 blocked for more than 120 seconds.
Jun  9 12:36:05 node42 kernel:      Not tainted 2.6.32-431.17.1.el6.x86_64 #1
Jun  9 12:36:05 node42 kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Jun  9 12:36:05 node42 kernel: dbinstal      D 0000000000000000     0 36425  36424 0x00000080
Jun  9 12:36:05 node42 kernel: ffff88081af03e28 0000000000000086 0000000000000000 ffffffff8105af80
Jun  9 12:36:05 node42 kernel: ffff880833013578 ffff8808258b1540 ffff88081af03df8 ffffffff8100988e
Jun  9 12:36:05 node42 kernel: ffff8808258b1af8 ffff88081af03fd8 000000000000fbc8 ffff8808258b1af8
Jun  9 12:36:05 node42 kernel: Call Trace:
Jun  9 12:36:05 node42 kernel: [<ffffffff8105af80>] ? __dequeue_entity+0x30/0x50
Jun  9 12:36:05 node42 kernel: [<ffffffff8100988e>] ? __switch_to+0x26e/0x320
Jun  9 12:36:05 node42 kernel: [<ffffffffa04bc0a0>] ? gfs2_glock_demote_wait+0x0/0x20 [gfs2]
Jun  9 12:36:05 node42 kernel: [<ffffffffa04bc0ae>] gfs2_glock_demote_wait+0xe/0x20 [gfs2]
Jun  9 12:36:05 node42 kernel: [<ffffffff81528e4f>] __wait_on_bit+0x5f/0x90
Jun  9 12:36:05 node42 kernel: [<ffffffffa04bc0a0>] ? gfs2_glock_demote_wait+0x0/0x20 [gfs2]
Jun  9 12:36:05 node42 kernel: [<ffffffff81528ef8>] out_of_line_wait_on_bit+0x78/0x90
Jun  9 12:36:05 node42 kernel: [<ffffffff8109af80>] ? wake_bit_function+0x0/0x50
Jun  9 12:36:05 node42 kernel: [<ffffffff8106965a>] ? __cond_resched+0x2a/0x40
Jun  9 12:36:05 node42 kernel: [<ffffffffa04bdc9c>] gfs2_glock_dq_wait+0x3c/0x50 [gfs2]
Jun  9 12:36:05 node42 kernel: [<ffffffffa04c9dae>] gfs2_flock+0x7e/0xa0 [gfs2]
Jun  9 12:36:05 node42 kernel: [<ffffffff811d992d>] sys_flock+0x10d/0x1c0
Jun  9 12:36:05 node42 kernel: [<ffffffff8100b072>] system_call_fastpath+0x16/0x1b