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From: Anthony Liguori <anthony@codemonkey.ws>
In-Reply-To: <503B82C6.5080007@redhat.com>
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Date: Mon, 27 Aug 2012 10:50:25 -0500
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Subject: Re: [Qemu-devel] [PATCH v2 6/6] i8259: add
	-no-spurious-interrupt-hack option
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Matthew Ogilvie <mmogilvi_qemu@miniinfo.net>, qemu-devel@nongnu.org

Paolo Bonzini <pbonzini@redhat.com> writes:

> Il 27/08/2012 15:55, Anthony Liguori ha scritto:
>>> > This patch provides a way to optionally suppress spurious interrupts,
>>> > as a workaround for systems described below:
>>> >
>>> > Some old operating systems do not handle spurious interrupts well,
>>> > and qemu tends to generate them significantly more often than
>>> > real hardware.
>> This is the wrong approach.  You add a LostTickPolicy property to the
>> i8259 device.
>
> Isn't the i8254 the one that would need a LostTickPolicy?

You're right, I too quickly read this patch and misunderstood what it's
doing.

Regards,

Anthony Liguori

>
> But this seems like a bug that is either in the i8259 emulation, or in
> the firmware.  Your own suggestion of setting IRQ2 to level-triggered in
> SeaBIOS is definitely a good one.

>
> Paolo