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From: Juan Quintela <quintela@redhat.com>
In-Reply-To: <20171215115123.12959-1-dgilbert@redhat.com> (David Alan
	Gilbert's message of "Fri, 15 Dec 2017 11:51:23 +0000")
References: <20171215115123.12959-1-dgilbert@redhat.com>
Reply-To: quintela@redhat.com
Date: Wed, 27 Dec 2017 23:14:43 +0100
Message-ID: <87o9mjbyy4.fsf@secure.laptop>
MIME-Version: 1.0
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Subject: Re: [Qemu-devel] [PATCH] migration: Guard ram_bytes_remaining
 against early call
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To: "Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>
Cc: qemu-devel@nongnu.org, peterx@redhat.com

"Dr. David Alan Gilbert (git)" <dgilbert@redhat.com> wrote:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
>
> Calling ram_bytes_remaining during the early part of setup is unsafe
> because the ram_state isn't yet initialised.
>
> This can happen in the sequence:
>    migrate
>    migrate_cancel
>    info migrate
>
> if the migrate sticks trying to connect (e.g. to an unresponsive
> destination due to the connect timeout).  Here 'info migrate' sees
> a state of CANCELLING and so assumes the migrate has partially happened.
>
> partial fix for:
> RH bz: https://bugzilla.redhat.com/show_bug.cgi?id=1525899
> Reported-by: Xianxian Wang <xianwang@redhat.com>
> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

Reviewed-by: Juan Quintela <quintela@redhat.com>