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Date: Wed, 02 May 2012 18:40:33 +0200
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Subject: Re: [Qemu-devel] [libvirt] [RFC 0/5] block: File descriptor passing
	using -open-hook-fd
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To: Eric Blake <eblake@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>, libvir-list@redhat.com, Anthony Liguori <aliguori@us.ibm.com>, Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>, qemu-devel@nongnu.org

Il 01/05/2012 22:56, Eric Blake ha scritto:
> What sort
> of timing restrictions are there?  For example, the proposed
> 'drive-reopen' command (probably now delegated to qemu 1.2) would mean
> that qemu would be calling back into libvirt in order to do the reopen.
>  If libvirt takes its time in passing back an open fd, is it going to
> starve qemu from answering unrelated monitor commands in the meantime?
> I definitely want to make sure we avoid deadlock where libvirt is
> waiting on a monitor command, but the monitor command is waiting on
> libvirt to pass an fd.

FWIW I'm going to kill drive-reopen in favor of something like
block-job-complete that will not require reopening (it will require
opening the backing files though, and that can also take time).

Paolo