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Date: Wed, 28 Dec 2011 10:17:10 -0800
From: Stephen Hemminger <shemminger@vyatta.com>
To: Bjarke Istrup Pedersen <gurligebis@gentoo.org>
Cc: Ben Hutchings <bhutchings@solarflare.com>, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, Roger Luethi <rl@hellgate.ch>
Subject: Re: [PATCH 1/1] via-rhine: Fix hanging with high CPU load on
 low-end broads.
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Looks like the hardware isn't really disabling interrupts correctly to support
NAPI. NAPI is supposed to be friendly and under load the work should move to
ksoftirqd. I suspect the IRQ management in this driver is borked.
There is some stupid spin loops in the IRQ handler that happen when looking for
Tx IRQ. I would run with debug set  and see if this is triggering.