ide-cs using 100% CPU

Hamie
2004-07-18T09:31:10Z

I have a thinkpad r50p, 1.6GHz CPU, 512MB memory running kernel
2.6.7-mm4 (Also tried 2.6.7, 2.6.6, 2.6.4 and a few others).

When reading from CF card (using ide-cs) the system is really stodgy and
consumes 100% CPU. Almost all of it waitIO according to top...

Now it's not the fact that I get lots of waitIO, but AFAIUI if a system
uses truckloads of waitIO, that should just mean that the system is idle
but there's some IO going on & a process is waiting for it to complete
(e.g. the way AIX does it).

Other processes should still be able to get CPU without any problems,
but my experience is that under Linux if waitio is due to reading the CF
card, the system essentially stops... The mouse still moves (Under X),
but... unwillingly... Jerking around all over the place...

Anyone know why this happens? Something busy waiting? (BUt that should
show as system cpu right?) or something taking out really long locks?