Hi,
I've got a machine which occasionally locks up. I can still sysrq it from
a serial console, so it's not entirely dead.
A sysrq-t learns me that it's got a large number of httpd processes stuck
in D state :
httpd D F7619440 2160 11635 2057 11636 (NOTLB)
dbb7ae14 cc9b0550 c33224a0 f7619440 de187604 00000000 000000b3 00000001
000000b3 00000000 ffffffff d374a550 c33224a0 0005b8d8 f04af800
000f75e7
d374a550 cc9b0550 cc9b0678 ef7d33ec ef7d33e8 cc9b0550 ef7d33fc
c041bf70
Call Trace:
[<c041bf70>] __mutex_lock_slowpath+0x92/0x43e
[<c0148f29>] generic_file_aio_write+0x5c/0xfa
[<c0148f29>] generic_file_aio_write+0x5c/0xfa
[<c0148f29>] generic_file_aio_write+0x5c/0xfa
[<c01746c9>] permission+0xad/0xcb
[<c01d9c4a>] ext3_file_write+0x3b/0xb0
[<c0166777>] do_sync_write+0xd5/0x130
[<c041d1bf>] _spin_unlock+0xb/0xf
[<c0135c13>] autoremove_wake_function+0x0/0x4b
[<c0166975>] vfs_write+0x1a3/0x1a8
[<c0166a39>] sys_write+0x4b/0x74
[<c0102c03>] sysenter_past_esp+0x54/0x75
After this, the machine is rendered useless (probably due to the fact that
disk IO isn't working anymore).
The lock debugging gives me this :
D httpd:11635 [cc9b0550, 116] blocked on mutex: [ef7d33e8]
{inode_init_once}
.. held by: httpd: 506 [d67e1000, 121]
... acquired at: generic_file_aio_write+0x5c/0xfa
I see similiar things as mentioned in http://lkml.org/lkml/2006/1/10/64,
with the difference that I'm not running software RAID or SATA (it's an
Areca ARC-1110).
I can't reproduce it until now, it 'just' happens. Can someone give me a
pointer where to start looking ?
Erich, I've CC-ed you since the machine is running an Areca RAID config.
It's also the only used disk subsystem in this machine.
Regards,
Igmar