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Date: Wed, 13 Aug 2008 15:06:41 +0100
From: Samuel Thibault <samuel.thibault@ens-lyon.org>
Subject: Re: [Qemu-devel] [PATCH] Flush pending AIO on reboot and shutdown.
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To: qemu-devel@nongnu.org

Gleb Natapov, le Wed 13 Aug 2008 16:59:41 +0300, a écrit :
> On Wed, Aug 13, 2008 at 02:46:08PM +0100, Samuel Thibault wrote:
> > Gleb Natapov, le Wed 13 Aug 2008 16:23:58 +0300, a écrit :
> > > If there is outstanding IDE IO when BIOS starts execution then IDE
> > > commands sent by BIOS will interfere with it and will leave IDE
> > > subsystem in unpredictable state. This can happen when system reboots
> > > unexpectedly without waiting for IO completion. Flushing IO before exit
> > > prevents data lose.
> > 
> > I'm wondering: isn't that what happens with real machines?
> > 
> With shutdown yes, but why not try harder. With reboot I don't think
> that in real HW you can hang IDE interface after reboot ;)

Mmm, I couldn't understand.

With real hardware, if you reboot into the bios the board is not
resetted either, and thus the interference is the same.

Samuel