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Date: Thu, 17 Jul 2003 22:20:53 +0200
From: Thomas Quinot <thomas@FreeBSD.ORG>
To: Daniel Lang <dl@leo.org>
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cc: freebsd-hackers@freebsd.org
cc: Thomas Quinot <thomas@FreeBSD.ORG>
Subject: Re: atapicam hangs system
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Le 2003-07-17, Daniel Lang écrivait :

> I found out, that the hangs do not appear (or way less likely),
> if the writing speed used is <= 12. But they seem to occur
> very likely if the (attempted) writing speed is like 48.

Hum, nasty, nasty. Looks like the amount of interrupts caused by
high-speed burning might trigger a race condition between two
instances of camisr(). camisr() does splcam(), but maybe this is not
sufficient to correctly prevent concurrent execution when interrupts
from the ATA driver occur. Maybe the freebsd-scsi people will have a
clearer idea of what is going on here.

Thomas.

-- 
    Thomas.Quinot@Cuivre.FR.EU.ORG