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Date: Sun, 27 Sep 2009 16:26:33 +0200
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] Re: [PATCHv2] qemu: target library, use it in msix
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Blue Swirl <blauwirbel@gmail.com>, qemu-devel@nongnu.org

On 09/27/2009 04:21 PM, Michael S. Tsirkin wrote:
>
>> How can the caller (except in your special case) know if it has a
>> quantity that will fit in 32 bits?
>>      
> It's actually not unusual for devices to limit addressing to 32 bit, whatever
> the bus supports.  For example, the value might come from a 32 bit pci
> bar, even on a 64 bit system this will get values 0 to 4G.
>    

What if the caller is a device that doesn't intentionally cripple itself?

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.