2.6.9 & 11 hang on ac/dc change

[William D Waddington <william.waddington@beezmo.com>]

In the course of trying to figure out why /sys/.../cpu0 isn't populated
when in APM mode, I discovered that the laptop hangs on the first (?)
attempt to write to the drive after a change of power source.

This is a ThinkPad T43.  I see the problem with both 2.6.9-1.667 and
2.6.11-1.14_FC3 (both FC3).  Doesn't seem to happen in ACPI mode.
I need APM since that suspends and hibernates will on TPs. (Including
this one)

It always leads to a filesystem check on reboot, and once it damaged
the partition so badly that it wouldn't reboot and "linux rescue" from
the FC3 DVD couldn't mount it.  That time, I got "journalling error"
messages on the console, and "abnormal status 0xD0 on port 0x1F7"
when I tried to shut down.

I can't write to the HD to try to capture anything, so I don't have
much diagnostic info.  I have posted the APM boot messages, FWIW:
http://www.beezmo.com/scratch/t43_fc3/dmesg.apm

Any place I should poke to track this one down?  If this doesn't belong
on lkml, please point me appropriately.

Thanks,
Bill (not subscribed but lurking on fa.linux.kernel)
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