Re: Reproducible SMP/SCSI Hangs under 2.0.xx

Jered Floyd (
Mon, 16 Dec 1996 17:16:51 EST

(Trimmed the Cc: list a bit...)

I, too, have had troubles with kernel lockups that are likely due to
an mmap problem, a race condition would seem to be a likely candidate. At
first I thought there was a problem in Linux/AFS, which I was building for
the SMP kernel, but further experiments showed that I could reproduce the
problem without AFS. (AFS does seem to make the problem occur more often,
presumably because mmap'ed file access takes longer for files that are on a
networked file system.)

I've talked to Alan Cox a bit about this, and am looking at the mmap/
memory management code to see if I can track this down, but I honestly
don't know where to begin. Any help would be appreciated.

The machine I have reproduced the problems on is a dual PPro 200/512k,
ASUS P65UP5 motherboard, BusLogic 958 SCSI card. Since this commonly
occurs with AFS, I don't believe the BusLogic driver is responsible.
(Although there might be some concern with the AFS cache...)

--Jered Floyd