Date: Mon, 21 Apr 1997 12:53:20 -0400 (EDT) From: "Donald J. Maddox" <root@cola110.scsn.net> To: current@FreeBSD.org Subject: Panics in kern_lock.c:lockstatus Message-ID: <199704211653.MAA00438@cola110.scsn.net>
next in thread | raw e-mail | index | archive | help
I have been getting panics that look like the following fairly
consistently of late:
------------------------------------------------------------------
Fatal trap 12: page fault while in kernel mode
fault virtual address = 0x44
fault code = supervisor read, page not present
instruction pointer = 0x8:0xf010e020
stack pointer = 0x10:0xf3dddf0c
frame pointer = 0x10:0xf3dddf0c
code segment = base 0x0, limit 0xfffff, type 0x1b
= DPL 0, pres 1, def32 1, gran 1
processor eflags = interrupt enabled, resume, IOPL=0
current process = 326 (reboot)
interrupt mask =
kernel: type 12 trap, cod=0
Stopped at _lockstatus+0x8: cmpw $0,0x10(%edx)
db>
--------------------------------------------------------------------
I haven't yet found a way to reproduce it with 100% reliability,
but the following often works:
1) Start something that does a lot of disk access, like
# cd /usr/src
# make clean cleandir cleandepend
2) In another shell, issue the the command: `ps -ax | grep make`
repeatedly in quick succession. Sometimes it takes 20 or
more repetitions to work, but eventually it will just hang,
and any subsequent invocations of ps will _always_ hang.
Top, however, will still work, and shows the shell that
started the original ps command in the 'thrd_s' state. All
the subsequent invocations of ps will show either 'thrd_s'
or 'pfslck' state.
3) After this, eventually the panic will occur. The example
above occured while rebooting with 'shutdown -r now', but
this does not always cause a panic.
-------------------------------------------------------------------
All of the above was done from xterms, using tcsh as the shell,
running as root.
The system is -current as of about 2 am this morning, but I have
been seeing this panic sporadically ever since the lite2 merge.
--
Donald J. Maddox
(dmaddox@scsn.net)
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199704211653.MAA00438>