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Date: Fri, 24 Jan 2014 14:33:19 +0100
From: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20140124133319.GH3342@dhcp-200-207.str.redhat.com>
References: <2fb3ea05d2e1ee06d578a0f2c53f56df1661401c.1389726691.git.jcody@redhat.com>
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In-Reply-To: <2fb3ea05d2e1ee06d578a0f2c53f56df1661401c.1389726691.git.jcody@redhat.com>
Subject: Re: [Qemu-devel] [PATCH] block: do not allow read-only=on and
 snapshot=on to be used together
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To: Jeff Cody <jcody@redhat.com>
Cc: pbonzini@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com

Am 14.01.2014 um 20:12 hat Jeff Cody geschrieben:
> Having both read-only=on and snapshot=on together does not make sense;
> currently, the read-only argument is effectively ignored for the
> temporary snapshot.  To prevent confusion, disallow the usage of both
> 'snapshot=on' and 'read-only=on'.
> 
> Signed-off-by: Jeff Cody <jcody@redhat.com>

This breaks in a surprising way:

$ softmmu/qemu-system-x86_64 -drive file=~/images/hd.img,snapshot=on
... works fine ...

$ qemu-system-x86_64 -drive file=~/images/hd.img -snapshot
qemu-system-x86_64: invalid option combination: read-only and snapshot

qemu-iotests case 051 catches this. I'll have to remove this patch and
the follow-up from the queue for now.

Kevin