[CentOS] kernel: Page has mapping still set - continues

Been having this problem, and posted about it before.  Thinking it was a
memory issue, I've replaced all memory on the server.  However, the
problem has continued.

Server is a Proliant DL380 (8GB RAM, 2 Xeon CPU), running CentOS 3.6, all
patches up-to-date.  Kernel is 2.4.21-40.ELsmp (problem seems to have
first manifested on kernel 2.4.21-37.0.1.ELsmp).  Disk is CCISS hardware
RAID-5, straight partitioning (no LVM).

This server runs an Oracle 10g instance, async I/O enabled to a NetApp
filer where most data is stored.

Traceback of latest failure follows (two crashes this morning).  Anyone
read these things well enough to tell me if there's any insight in this? 
There are no nVidia drivers loaded, only stock kernel modules.

Thanks in advance for any insight.
-Alan


Apr 10 05:32:22 db01-01 kernel: page not mapped.  erroring out.
Apr 10 05:32:22 db01-01 kernel: Page has mapping still set. This is a
serious situation. However if you
Apr 10 05:32:22 db01-01 kernel: are using the NVidia binary only module
please report this bug to
Apr 10 05:32:22 db01-01 kernel: NVidia and not to the linux kernel
mailinglist.
Apr 10 05:32:22 db01-01 kernel: ------------[ cut here ]------------
Apr 10 05:32:22 db01-01 kernel: kernel BUG at page_alloc.c:225!
Apr 10 05:32:22 db01-01 kernel: invalid operand: 0000
Apr 10 05:32:22 db01-01 kernel: sg nfs lockd sunrpc tg3 microcode
keybdev mousedev hid input ehci-hcd usb-uhci usbcore ext3 jbd cciss
sd_mod scsi_mod
Apr 10 05:32:22 db01-01 kernel: CPU:    1
Apr 10 05:32:22 db01-01 kernel: EIP:    0060:[<c0159560>]    Not tainted
Apr 10 05:32:22 db01-01 kernel: EFLAGS: 00010286
Apr 10 05:32:22 db01-01 kernel:
Apr 10 05:32:22 db01-01 kernel: EIP is at __free_pages_ok [kernel] 0x3e0
(2.4.21-40.ELsmp/i686)
Apr 10 05:32:22 db01-01 kernel: eax: 00000033   ebx: c797dd38   ecx:
00000001edx: c0387e98
Apr 10 05:32:22 db01-01 kernel: esi: f4402880   edi: 00000000   ebp:
00000000esp: cd7d5ec8
Apr 10 05:32:22 db01-01 kernel: ds: 0068   es: 0068   ss: 0068
Apr 10 05:32:22 db01-01 kernel: Process keventd (pid: 6, stackpage=cd7d5000)
Apr 10 05:32:22 db01-01 kernel: Stack: c02c1ea8 00000363 c000a750
ff0ea000 c0440280 00000000 cdbac000 efc21f00
Apr 10 05:32:22 db01-01 kernel: 00000000 00000001 00000001 00000086
dab95054 00000001 f4402880 00000000
Apr 10 05:32:22 db01-01 kernel: 00000000 c014cf3e 00000001 00000000
00000000 cd7d4000 00000000 00000e00
Apr 10 05:32:22 db01-01 kernel: Call Trace:   [<c014cf3e>] __iodesc_free
[kernel] 0xde (0xcd7d5f0c)
Apr 10 05:32:22 db01-01 kernel: [<c0161e9c>] kmap_high [kernel] 0x5c
(0xcd7d5f28)
Apr 10 05:32:22 db01-01 kernel: [<c014d87b>] __iodesc_read_finish
[kernel] 0x22b (0xcd7d5f38)
Apr 10 05:32:22 db01-01 kernel: [<c01302ca>] __run_task_queue [kernel]
0x6a (0xcd7d5f74)
Apr 10 05:32:22 db01-01 kernel: [<c013c9ad>] context_thread [kernel]
0x13d (0xcd7d5f8c)
Apr 10 05:32:22 db01-01 kernel: [<c013c870>] context_thread [kernel] 0x0
(0xcd7d5fe0)
Apr 10 05:32:22 db01-01 kernel: [<c01095cd>] kernel_thread_helper
[kernel] 0x5 (0xcd7d5ff0)
Apr 10 05:32:22 db01-01 kernel:
Apr 10 05:32:22 db01-01 kernel: Code: 0f 0b e1 00 33 17 2c c0 e9 6c fc
ff ff 9c 5a fa f0 fe 0d 70
Apr 10 05:32:22 db01-01 kernel:
Apr 10 05:32:22 db01-01 kernel: Kernel panic: Fatal exception




===========
Alan Sparks, UNIX/Linux Systems Administrator    <asparks at doublesparks.net>