Hi
Working with a June 29th pull of davem's tree I found a sequence of
events which poses a problem causing BUG and then Oops.
This impacts platforms with the mostek clock
kernel/main.c calls out time_init() which ultimatly leads to a call
of clock_init() which calls of_register_driver() for the mostek clock.
This occurs prior to the kobject, klist and friends being initialized
which occurs as postcore_initcall(of_bus_driver_init), This leads to
the BUGs and oops.
The clock initialization is needed prior to local_irq_enable
I have not found reasons for the postcore_initcall calls timing but
assume they're concrete for other platforms.
I have not found a work around.
Thanx
Ray
SILO boot: sm
Using /dev/ttya as console.
TYPE: SPARCserver 1000E
Ethernet address: 8:0:20:7e:19:ee
Boot time fixup v1.6. 4/Mar/98 Jakub Jelinek (jj@xxxxxxxxxxxxxx). Patching kerne
l for srmmu[TI Viking/MXCC]/io-unit
318MB HIGHMEM available.
PROM: Built device tree with 14005 bytes of memory.
Booting Linux...
Built 1 zonelists. Total pages: 130066
Kernel command line: root=/dev/sdc3 console=ttya
PID hash table entries: 1024 (order: 10, 4096 bytes)
BUG: warning at lib/kref.c:32/kref_get()
[f013df38 : get_bus+0x20/0x50 ] [f013dd04 : bus_add_driver+0x8/0xa8 ] [f025bc74
: sbus_setup_arch_props+0x30/0x54 ] [f02560a4 : found_version+0x5c/0x68 ] [f0255
7c8 : _etext+0x76c20/0x77458 ] [00000000 : __stext+0xfffc000/0x10 ]
BUG: warning at lib/kref.c:32/kref_get()
[f0109d7c : kobject_init+0x38/0x70 ] [f0109f64 : kobject_register+0x10/0x44 ] [f
013dd44 : bus_add_driver+0x48/0xa8 ] [f025bc74 : sbus_setup_arch_props+0x30/0x54
] [f02560a4 : found_version+0x5c/0x68 ] [f02557c8 : _etext+0x76c20/0x77458 ] [0
0000000 : __stext+0xfffc000/0x10 ]
Unable to handle kernel NULL pointer dereference
tsk->{mm,active_mm}->context = ffffffff
tsk->{mm,active_mm}->pgd = fc000000
swapper(0): Oops [#1]
PSR: 40401fc2 PC: f0109ef4 NPC: f0109ef8 Y: 00000000 Not tainted
PC: <kobject_add+0xec/0x14c>
%G: f02177d8 f0110db8 404010e1 40401fe6 f003af34 f027ec00 f0012000 00000100
%O: f02177e0 f0217260 00000000 00000073 ffffffff ffffffff f0013d90 f0109f10
RPC: <kobject_add+0x108/0x14c>
%L: 00000000 f02177ec fffffffd f0217248 00000040 00000000 0000001f f0013d08
%I: f0217244 00000014 f01e8582 f0013eb0 f027f5e0 ffffffff f0013df8 f0109f6c
Caller[f0109f6c]: kobject_register+0x18/0x44
Caller[f013dd44]: bus_add_driver+0x48/0xa8
Caller[f025bc74]: sbus_setup_arch_props+0x30/0x54
Caller[f02560a4]: found_version+0x5c/0x68
Caller[f02557c8]: _etext+0x76c20/0x77458
Caller[00000000]: __stext+0xfffc000/0x10
Instruction DUMP: d4022004 d026201c d2222004 <d2228000> d4226004 d0062028 90
022010 c02a0000 10bfffd5
Program terminated
Type help for more information
<#0> ok
