From mboxrd@z Thu Jan  1 00:00:00 1970
From: Viktor Babrian <babrian.viktor@renyi.mta.hu>
Subject: Re: [PATCH 3.19-rc3] c_can: SIE disabled when berr-reporting is off
 to reduce irq flood
Date: Mon, 19 Jan 2015 12:32:41 +0100 (CET)
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To: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Viktor Babrian <babrian.viktor@renyi.mta.hu>, Andri Yngvason <andri.yngvason@marel.com>, Tom Evans <tom_usenet@optusnet.com.au>, linux-can@vger.kernel.org

>> Also note that when the system is flooded by these error interrupts,
>> system performace degrades so much that serial terminal echo becomes
>> annoyingly long. When this happens, I wonder how usable the "accurate"
>> state transition reports are anyway.
>
> As I said, they are vital to some applications. The bus error limiting
> series will follow.

OK. possible compromise is to enable buserr interrupts in Warning state 
only. This way Warning->Passive transition is detected for sure.
Interrupt flood can only occur if error counter could stay between 96 and 
128 which can hardly happen if bus is full of error.