Hello.
Just got this Oops:
---
ksymoops 2.4.3 on i686 2.4.19-pre3-ac6. Options used
-V (default)
-k /proc/ksyms (default)
-l /proc/modules (default)
-o /lib/modules/2.4.19-pre3-ac6/ (default)
-m /usr/src/linux/System.map (default)
Warning: You did not tell me where to find symbol information. I will
assume that the log matches the kernel and modules that are running
right now and I'll use the default options above for symbol resolution.
If the current kernel and/or modules do not match the log, you can get
more accurate output by telling me the kernel version and where to find
map, modules, ksyms etc. ksymoops -h explains the options.
Warning (compare_maps): ksyms_base symbol
GPLONLY_vmalloc_to_page not found in System.map. Ignoring ksyms_base entry
Mar 26 01:11:26 localhost kernel: Unable to handle kernel NULL pointer dereference at virtual address 00000000
Mar 26 01:11:26 localhost kernel: c0131fb3
Mar 26 01:11:26 localhost kernel: *pde = 00000000
Mar 26 01:11:26 localhost kernel: Oops: 0002
Mar 26 01:11:26 localhost kernel: CPU: 0
Mar 26 01:11:26 localhost kernel: EIP: 0010:[page_referenced+51/80] Not tainted
Mar 26 01:11:26 localhost kernel: EIP: 0010:[<c0131fb3>] Not tainted
Using defaults from ksymoops -t elf32-i386 -a i386
Mar 26 01:11:26 localhost kernel: EFLAGS: 00210286
Mar 26 01:11:26 localhost kernel: eax: 00000000 ebx: 00000005 ecx: c9211d48 edx: ffffffff
Mar 26 01:11:26 localhost kernel: esi: 00000002 edi: c0267bdc ebp: 00000222 esp: c1375fa0
Mar 26 01:11:26 localhost kernel: ds: 0018 es: 0018 ss: 0018
Mar 26 01:11:26 localhost kernel: Process kswapd (pid: 4, stackpage=c1375000)
Mar 26 01:11:26 localhost kernel: Stack: c117601c c1176038 c012c5f7 ffffbd1e c1374000 c0267c04 00000000 000004aa
Mar 26 01:11:26 localhost kernel: 00009a1b c0267bdc 000004aa 0008e000 c012cf2c c0267bdc 00000006 00000000
Mar 26 01:11:26 localhost kernel: 00010f00 cffe7fb8 c0105000 0008e000 c0105596 00000000 c012ccc0 c027dfdc
Mar 26 01:11:26 localhost kernel: Call Trace: [refill_inactive_zone+535/704] [kswapd+620/704]
[_stext+0/32] [kernel_thread+38/48] [kswapd+0/704]
Mar 26 01:11:26 localhost kernel: Call Trace: [<c012c5f7>] [<c012cf2c>] [<c0105000>] [<c0105596>] [<c012ccc0>]
Mar 26 01:11:27 localhost kernel: Code: 0f b3 18 19 d2 8b 09 85 d2 8d 46 01 0f 45 f0 85 c9 75 ea 5b
>>EIP; c0131fb2 <page_referenced+32/50> <=====
Trace; c012c5f6 <refill_inactive_zone+216/2c0>
Trace; c012cf2c <kswapd+26c/2c0>
Trace; c0105000 <_stext+0/0>
Trace; c0105596 <kernel_thread+26/30>
Trace; c012ccc0 <kswapd+0/2c0>
Code; c0131fb2 <page_referenced+32/50>
00000000 <_EIP>:
Code; c0131fb2 <page_referenced+32/50> <=====
0: 0f b3 18 btr %ebx,(%eax) <=====
Code; c0131fb4 <page_referenced+34/50>
3: 19 d2 sbb %edx,%edx
Code; c0131fb6 <page_referenced+36/50>
5: 8b 09 mov (%ecx),%ecx
Code; c0131fb8 <page_referenced+38/50>
7: 85 d2 test %edx,%edx
Code; c0131fba <page_referenced+3a/50>
9: 8d 46 01 lea 0x1(%esi),%eax
Code; c0131fbe <page_referenced+3e/50>
c: 0f 45 f0 cmovne %eax,%esi
Code; c0131fc0 <page_referenced+40/50>
f: 85 c9 test %ecx,%ecx
Code; c0131fc2 <page_referenced+42/50>
11: 75 ea jne fffffffd
<_EIP+0xfffffffd> c0131fae <page_referenced+2e/50>
Code; c0131fc4 <page_referenced+44/50>
13: 5b pop %ebx
2 warnings issued. Results may not be reliable.
---
page_referenced() is really very small
function, so I beleive finding the faulting
place would not be difficult:)
The strange thing, however, that swap was
completely empty and the load was about
zero, so I don't have any ideas about what
kswapd were doing at that moment.
/proc/meminfo:
total: used: free: shared: buffers: cached:
Mem: 262750208 258428928 4321280 0 27529216 79020032
Swap: 542826496 0 542826496
MemTotal: 256592 kB
MemFree: 4220 kB
MemShared: 0 kB
Buffers: 26884 kB
Cached: 77168 kB
SwapCached: 0 kB
Active: 218456 kB
Inact_dirty: 4384 kB
Inact_clean: 6660 kB
Inact_target: 45900 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 256592 kB
LowFree: 4220 kB
SwapTotal: 530104 kB
SwapFree: 530104 kB
Committed_AS: 205908 kB