kernel crash on Intel 386EX

[Edelhard Becker]

Hi,

we now have a kernel (2.6.8, rather minimal configuration due to
limited resources of course) and RTAI modules (3.1) for a 386 (16MB
RAM, no swap).  rtai_hal.ko loads fine, but when loading rtai_lxrt.ko
the kernel crashes:

| Adeos: Domain RTAI registered.
| RTAI[hal]: 3.1 mounted over Adeos 2.6r7/x86.
| RTAI[hal]: compiled with gcc version 3.3.5 (Debian 1:3.3.5-1).
| RTAI[malloc]: loaded (global heap size=131072 bytes).
| Unable to handle kernel paging request at virtual address d5902e22
|  printing eip:
| c011035b
| *pde = 00000000
| Oops: 0000 [#1]
| PREEMPT
| Modules linked in: rtai_lxrt rtai_hal
| CPU:    0
| EIP:    0060:[<c011035b>]    Not tainted
| EFLAGS: 00010883   (2.6.8-386ex)
| EIP is at do_page_fault+0x3b/0x4b7
| eax: c05bc000   ebx: 00000000   ecx: 0000007b   edx: 0000007b
| esi: d5902dba   edi: c0110320   ebp: 746961df   esp: c05bdf98
| ds: 007b   es: 007b   ss: 0068
| Adeos domain RTAI
| Stack: 61685f6c 656c646e 74720072 7465675f 00030001 6769726f 00000000 00000000
|        00000000 00000000 745f7472 5f6b7361 656b616d 7265705f 69646f69 65725f63
|        6974616c 6e5f6576 74720073 7361745f 616d5f6b 705f656b 6f697265 c05be004
| Call Trace:
| Not executing in the root domain, no trace available
| Code: 8b 56 68 89 54 24 04 8b 50 14 8b 00 8b 40 14 f7 d0 81 e2 ff
|  <0>Kernel panic: Fatal exception in interrupt
| In interrupt handler - not syncing
|  <4>Adeos: Current domain=RTAI on CPU #0 [stackbase=c052a000]
|     RTAI[cpuid=0]: priority=200, status=0x0, pending_hi=0x0
|    Linux[cpuid=0]: priority=100, status=0x0, pending_hi=0x3

Does anybody have an idea in which direction to search/debug for the
problem?  Some more info about the hardware:

| # cat /proc/cpuinfo /proc/devices /proc/interrupts /proc/meminfo
| processor       : 0
| vendor_id       : unknown
| cpu family      : 3
| model           : 0
| model name      : 386
| stepping        : unknown
| fdiv_bug        : no
| hlt_bug         : no
| f00f_bug        : no
| coma_bug        : no
| fpu             : no
| fpu_exception   : no
| cpuid level     : -1
| wp              : no
| flags           :
| bogomips        : 8.19
| 
| Character devices:
|   1 mem
|   2 pty
|   3 ttyp
|   4 /dev/vc/0
|   4 tty
|   4 ttyS
|   5 /dev/tty
|   5 /dev/console
|   5 /dev/ptmx
|   7 vcs
|  10 misc
|  13 input
| 128 ptm
| 136 pts
| 254 devfs
| 
| Block devices:
|   1 ramdisk
|   3 hd
|            CPU0
|   0:     390536          XT-PIC  timer
|   2:          0          XT-PIC  cascade
|   3:       1743          XT-PIC  serial
|  12:      12642          XT-PIC  eth0
|  14:          8          XT-PIC  hd
| NMI:          0
| ERR:          0
| MemTotal:        13888 kB
| MemFree:          2736 kB
| Buffers:             0 kB
| Cached:           6676 kB
| SwapCached:          0 kB
| Active:           6772 kB
| Inactive:         1948 kB
| HighTotal:           0 kB
| HighFree:            0 kB
| LowTotal:        13888 kB
| LowFree:          2736 kB
| SwapTotal:           0 kB
| SwapFree:            0 kB
| Dirty:               0 kB
| Writeback:           0 kB
| Mapped:           4792 kB
| Slab:             2104 kB
| Committed_AS:     5424 kB
| PageTables:        124 kB
| VmallocTotal:  1023976 kB
| VmallocUsed:         8 kB
| VmallocChunk:  1023968 kB
| #

Thanks and greetings,
Edelhard Becker
-- 
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