Re: [PATCH] serial: 8250, increase PASS_LIMIT

From: Jiri Slaby
Date: Mon Jun 06 2011 - 09:49:34 EST

On 06/06/2011 02:09 PM, Alan Cox wrote:
> On Sun, 5 Jun 2011 22:51:49 +0200
> Jiri Slaby <jslaby@xxxxxxx> wrote:
>> From: Jiri Slaby <jirislaby@xxxxxxxxx>
>> With virtual machines like qemu, it's pretty common to see "too much
>> work for irq4" messages nowadays. This happens when a bunch of output
>> is printed on the emulated serial console. This is caused by too low
>> PASS_LIMIT. When ISR loops more than the limit, it spits the message.
>> I've been using a kernel with doubled the limit and I couldn't see no
>> problems. Maybe it's time to get rid of the message now?
> We need a limit to deal with hangs caused by misconfiguration /
> mis-detection on ISA ports in particular but we can certainly bump the
> limit to handle poor emulations.

Yeah, I meant it that way (get rid of the message by bumping the limit
-- this patch).

suse labs
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