Got this at system shutdown, while trying to unmount one of three ext4 file
system (note - the filesystems were all originally ext3, mounted as ext4, if
that matters).
RFE - if it's going to print the mballoc stats, it should at least dump
a major/minor pair so that I can tell which of my 3 ext4 filesystems each
one is talking about. :)
[ 297.865667] EXT4-fs: mballoc: 0 blocks 0 reqs (0 success)
[ 297.868397] EXT4-fs: mballoc: 0 extents scanned, 0 goal hits, 0 2^N hits, 0 breaks, 0 lost
[ 297.871459] EXT4-fs: mballoc: 0 generated and it took 0
[ 297.874532] EXT4-fs: mballoc: 0 preallocated, 0 discarded
[ 297.900378] ------------[ cut here ]------------
[ 297.903618] WARNING: at fs/namespace.c:611 mntput_no_expire+0xd8/0x145()
[ 297.906962] Hardware name: Latitude D820
[ 297.910231] Modules linked in: ext4 jbd2 crc16 [last unloaded: scsi_wait_scan]
[ 297.913357] Pid: 1783, comm: umount Not tainted 2.6.31-rc4-mmotm0730 #6
[ 297.916352] Call Trace:
[ 297.918164] [<ffffffff8103fb1d>] warn_slowpath_common+0x77/0x8f
[ 297.919706] [<ffffffff8103fb44>] warn_slowpath_null+0xf/0x11
[ 297.921172] [<ffffffff810e80bf>] mntput_no_expire+0xd8/0x145
[ 297.922797] [<ffffffff810e86d0>] sys_umount+0x2de/0x30d
[ 297.924312] [<ffffffff810669d6>] ? trace_hardirqs_on_caller+0x121/0x145
[ 297.925776] [<ffffffff8100b2ab>] system_call_fastpath+0x16/0x1b
[ 297.927343] ---[ end trace 6987d23c89c53046 ]---
[ 297.982931] EXT4-fs: mballoc: 0 blocks 0 reqs (0 success)
[ 297.984651] EXT4-fs: mballoc: 0 extents scanned, 0 goal hits, 0 2^N hits, 0 breaks, 0 lost
[ 297.986141] EXT4-fs: mballoc: 0 generated and it took 0
[ 297.987772] EXT4-fs: mballoc: 0 preallocated, 0 discarded
[ 297.993872] EXT4-fs: mballoc: 0 blocks 0 reqs (0 success)
[ 297.995383] EXT4-fs: mballoc: 0 extents scanned, 0 goal hits, 0 2^N hits, 0 breaks, 0 lost
[ 297.996974] EXT4-fs: mballoc: 0 generated and it took 0
[ 297.998595] EXT4-fs: mballoc: 0 preallocated, 0 discarded
[ 301.239272] sd 0:0:0:0: [sda] Synchronizing SCSI cache
[ 301.244884] Restarting system.
[ 301.247821] machine restart