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Date: Mon, 30 Apr 2012 11:57:16 +0200
From: Clemens Ladisch <clemens@ladisch.de>
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To: Jeroen Van den Keybus <jeroen.vandenkeybus@gmail.com>
CC: Josh Boyer <jwboyer@gmail.com>, Borislav Petkov <borislav.petkov@amd.com>,
        andymatei@gmail.com, "Huang, Shane" <Shane.Huang@amd.com>,
        Borislav Petkov <bp@amd64.org>, linux-kernel@vger.kernel.org
Subject: Re: Unhandled IRQs on AMD E-450
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Jeroen Van den Keybus wrote:
> - Detect stuck interrupts after a number (5) of consecutive unhandled
> IRQs within a specified time frame (100ms).

Why 5?  This threshold is likely to be too low; fast consecutive interrupts
can easily happen more often with a very busy device, while an actual stuck
interrupt will call the handler in an endless loop and very quickly result
in many thousands of calls.

> --- linux-3.2.16.orig/include/linux/irqdesc.h	2012-04-23
> 00:31:32.000000000 +0200

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Regards,
Clemens