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Date: Fri, 27 Mar 2009 13:53:31 +0300
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] honor IDE_DMA_BUF_SECTORS
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To: qemu-devel@nongnu.org

Samuel Thibault wrote:
> Avi Kivity, le Fri 27 Mar 2009 12:52:15 +0300, a =E9crit :
>  =20
>> However implementing DMA limits like you propose=20
>> (IDE_DMA_BUF_SECTORS) will not fix the bug, only reduce performance.
>>    =20
>
> Have you read what I wrote? v
>  =20

You can't have a good flamewar if you read what people actually write. =20
Maybe I'm confused by $subject.

>> block-raw-posix need not do that, just a while loop.
>>    =20
>
> For the synchronous interface, yes. For the asynchronous interface,
> short reads could happen too... (unfortunately we are aware of that too
> late for queuing other requests and getting efficiency).
>  =20

Currently block-raw-posix uses synchronous I/O even for asynchronous=20
requests (using threads) so the fix is the same in both cases.

--=20
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.