Re: [Xen-devel] HVM guest with file backed disks using loop devi

To:	"Daniel P. Berrange" <berrange@xxxxxxxxxx>
Subject:	Re: [Xen-devel] HVM guest with file backed disks using loop devices ?
From:	"Andrew Warfield" <andrew.warfield@xxxxxxxxxxxx>
Date:	Wed, 22 Nov 2006 10:17:06 -0800
Cc:	xen-devel@xxxxxxxxxxxxxxxxxxx, Ewan Mellor <ewan@xxxxxxxxxxxxx>
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Ok, that makes sense now. This raises another question though - is it possible
to make the PV-for-HVM drivers work against the blktap backend ? The loop
back driver has bad data integrity issues upon crash & poor performance in
comparison to blktap, so I'd really like to avoid loopback altogether.


So would I.  One reasonably straight-forward option here would be to
just do an xm block-attach in the ioemu block connect stage -- this
will add extra bounces through the kernel, but should work.

An alternate solution would be to build a direct bridge from qemu to
the tapdisk process or the tapdisk driver plugins... likely a bit more
work though.

patches/ideas welcome... ;)

a.

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Re: [Xen-devel] HVM guest with file backed disks using loop devices ?