T23 lock up after enter KDB either on 6-STABLE or 7-CURRENT

[Ren Zhen]

After I login, press Ctrl+Alt+ESC, kernel says:
KDB: enter: manual escape to debugger
[thread pid 16 tid 100014 ]
Stopped at       kdb_enter+0x2b: nop
db>

Then, my T23 lock up. I can only switch off the computer.

But, I use "boot -d" at booting kdb will work fine. I press c it continue.
When "login:" displayed on the screen, I enter the KDB, it lock up again.


Both 6-STABLE and 7-CURRENT have this problem.

My T23's model is 2647-4NC. Piii 1.13 256M*2 SDR. I have uninstalled one
DIMM, but it seems to have no help to this problem.

My kernel configuration file is GENERIC with following debug options:
options KDB
options DDB
options GDB
options INVARIANTS
options INVARIANT_SUPPORT
options WITNESS
options WITNESS_SKIPSPIN