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Date: Tue, 9 Mar 2010 19:26:06 +0000
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] Re: bs->enable_write_cache and the guest ABI
Message-ID: <20100309192606.GD11042@shareable.org>
References: <4B93BB4A.8090605@redhat.com> <m3vdd7yulg.fsf@trasno.mitica>
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To: Avi Kivity <avi@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>, qemu-devel <qemu-devel@nongnu.org>, Juan Quintela <quintela@redhat.com>

Avi Kivity wrote:
> On 03/09/2010 01:00 AM, Jamie Lokier wrote:
> >Avi Kivity wrote:
> >   
> >>I think we have to go with a qdev property as Christoph suggests.  Then
> >>it becomes the management's responsibility to set it right.
> >>     
> >How can the management be expected to know or follow dynamically
> >changing guest state?  There guests which disable a drive's write
> >cache in some application scripts, and others which enable it in boot
> >scripts.  That's not something management should be knowing about.
> >   
> 
> The flag indicates whether the drive has a write cache or not.

Ok, thanks, I was confused by the name saying "enable" not "has".

I presume the dynamic actually-enabled-write-cache guest device state
is dealt with properly, then?

-- Jamie