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Date: Fri, 15 Sep 2017 14:41:32 +0800
From: Peter Xu <peterx@redhat.com>
Message-ID: <20170915064132.GP3617@pxdev.xzpeter.org>
References: <20170915054404.19914-1-famz@redhat.com>
	<20170915054404.19914-2-famz@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 1/3] migration: Allow ram_save_cleanup to
 be called with empty state
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To: Fam Zheng <famz@redhat.com>
Cc: qemu-devel@nongnu.org, "Dr. David Alan Gilbert" <dgilbert@redhat.com>, Juan Quintela <quintela@redhat.com>, qemu-stable@nongnu.org

On Fri, Sep 15, 2017 at 01:44:02PM +0800, Fam Zheng wrote:
> So that we can do cleanup unconditionally at the end of main().
> 
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
>  migration/ram.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/migration/ram.c b/migration/ram.c
> index e18b3e2d4f..37e6a71241 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -1365,6 +1365,9 @@ static void ram_save_cleanup(void *opaque)
>      RAMState **rsp = opaque;
>      RAMBlock *block;
>  
> +    if (!rsp || !*rsp) {
> +        return;
> +    }
>      /* caller have hold iothread lock or is in a bh, so there is
>       * no writing race against this migration_bitmap
>       */
> -- 
> 2.13.5
> 

Instead of take special care on RAM, how about check in
migrate_fd_cancel(), and return directly if migration_is_idle()?

-- 
Peter Xu