2.4.21-pre2 hdparm Kernel Oops

Ok. This is the oops (recorded with digital camera and re-typed in as /var/log/messages et. al. had nothing). The controller is:
00:02.5 IDE interface: Silicon Integrated Systems [SiS] 5513 [IDE] (rev d0)

The error message when I run /sbin/hdparm -d1 -c3 -m16 -k1 /dev/hdb and /sbin/hdparm -d1 -c3 -m16 -k1 /dev/hda is:

 IO_support     =  3 (32-bit w/sync)
 using_dma      =  1 (on)
 keepsettings   =  1 (on)
kernel BUG in header file at line 155
kernel BUG at panic.c:141!
invalid operand: 0000
CPU:    0
EIP:    0010:[<c011af67>]       Not tainted
EFLAGS: 00010282
eax: 00000026   ebx: 00000000   ecx: f7bdc000  edx: 00000000
esi: c031c760   edi: 00001000   ebp: 00000000  esp: f7bddd50
ds: 0018  es: 0018  ss: 0018
Process hdparm (pid: 1160, stackpage=f7bdd000)
Stack: c02560a0 0000009b c01b8181 0000009b 00000000 00000014 0000008c
00000007
       f7eb8000 f7eba000 c031c810 00000000 c031c760 c01b8374 c031c760
f7eb0400
       00000002 c0180579 00000000 c031c760 c031c760 c031c810 f7eb0400
c031c760
Call Trace:    [<c01b8181>] [<c01b8374>] [<c0180579>] [<c01b889f>]

[<c01af8b9>]
[<c01a543e>] [<c0180579>] [<c01ae511>] [<c01ae68b>] [<c01aebb2>]
[<c01b7f40>]
[<c01089d5>] [<c0108b54>] [<c0117480>] [<c010b1f8>] [<c0117480>]
[<c01174a3>]
[<c012ac1b>] [<c012ba86>] [<c012bdd3>] [<c0117480>] [<c0107504>]

Code: 0f 0b 8d 00 bf 6d 25 c0 90 eb fe 8d b4 26 00 00 00 00 8d bc
 <0>Kernel panic: Aiee, killing interrupt handler!

In interrupt handler - not syncing

The results of ksymoops on the above:
[root@localhost bob]# uname -r
2.4.21-pre2
[root@localhost bob]# ksymoops -v /data/kernel/temp/linux/vmlinux -m /boot/System.map-2.4.21-pre2 /home/bob/oops.file
ksymoops 2.4.8 on i686 2.4.21-pre2. Options used
-v /data/kernel/temp/linux/vmlinux (specified)
-k /proc/ksyms (default)
-l /proc/modules (default)
-o /lib/modules/2.4.21-pre2/ (default)
-m /boot/System.map-2.4.21-pre2 (specified)

kernel BUG in header file at line 155 kernel BUG at panic.c:141!

invalid operand: 0000
CPU:    0
EIP:    0010:[<c011af67>]  Not tainted

Using defaults from ksymoops -t elf32-i386 -a i386
EFLAGS: 00010282
eax: 00000026 ebx: 00000000 ecx: f7bdc000 edx: 00000000
esi: c031c760 edi: 00001000 ebp: 00000000 esp: f7bddd50
ds: 0018 es: 0018 ss: 0018
Process hdparm (pid: 1160, stackpage=f7bdd000)

Stack: c02560a0 0000009b c01b8181 0000009b 00000000 00000014 0000008c
00000007
       f7eb8000 f7eba000 c031c810 00000000 c031c760 c01b8374 c031c760
f7eb0400
       00000002 c0180579 00000000 c031c760 c031c760 c031c810 f7eb0400
c031c760
Call Trace:    [<c01b8181>] [<c01b8374>] [<c0180579>] [<c01b889f>]

[<c01af8b9>]
[<c01a543e>] [<c0180579>] [<c01ae511>] [<c01ae68b>] [<c01aebb2>]
[<c01b7f40>]
[<c01089d5>] [<c0108b54>] [<c0117480>] [<c010b1f8>] [<c0117480>]
[<c01174a3>]
[<c012ac1b>] [<c012ba86>] [<c012bdd3>] [<c0117480>] [<c0107504>]

Code: 0f 0b 8d 00 bf 6d 25 c0 90 eb fe 8d b4 26 00 00 00 00 8d bc

Trace; c01b8181 <ide_build_sglist+181/1a0> Trace; c01b8374 <ide_build_dmatable+54/1a0> Trace; c0180579 <add_timer_randomness+d9/f0> Trace; c01b889f <__ide_dma_read+3f/150> Trace; c01af8b9 <do_rw_disk+1f9/760> Trace; c01a543e <ide_wait_stat+fe/130> Trace; c0180579 <add_timer_randomness+d9/f0> Trace; c01ae511 <start_request+1c1/240> Trace; c01ae68b <ide_do_request+ab/1a0> Trace; c01aebb2 <ide_intr+f2/130> Trace; c01b7f40 <ide_dma_intr+0/c0> Trace; c01089d5 <handle_IRQ_event+45/70> Trace; c0108b54 <do_IRQ+64/a0>
Trace; c0117480 <do_page_fault+0/523> Trace; c010b1f8 <call_do_IRQ+5/d> Trace; c0117480 <do_page_fault+0/523> Trace; c01174a3 <do_page_fault+23/523> Trace; c012ac1b <zap_pte_range+eb/110> Trace; c012ba86 <unmap_fixup+136/150> Trace; c012bdd3 <do_munmap+283/2a0> Trace; c0117480 <do_page_fault+0/523> Trace; c0107504 <error_code+34/3c>

Code; c011af67 <__out_of_line_bug+17/30> 00000000 <_EIP>:
Code; c011af67 <__out_of_line_bug+17/30> <=====
0: 0f 0b ud2a <=====
Code; c011af69 <__out_of_line_bug+19/30>
2: 8d 00 lea (%eax),%eax
Code; c011af6b <__out_of_line_bug+1b/30>
4: bf 6d 25 c0 90 mov $0x90c0256d,%edi
Code; c011af70 <__out_of_line_bug+20/30>
9: eb fe jmp 9 <_EIP+0x9> c011af70
<__out_of_line_bug+20/30>
Code; c011af72 <__out_of_line_bug+22/30>
b: 8d b4 26 00 00 00 00 lea 0x0(%esi,1),%esi
Code; c011af79 <__out_of_line_bug+29/30>
12: 8d bc 00 00 00 00 00 lea 0x0(%eax,%eax,1),%edi

<0>Kernel panic: Aiee, killing interrupt handler!

[root@localhost root]#

Thanks,
Bob