On Mon, Sep 26, 2016 at 01:29:58PM +0800, Lin Ma wrote:
> if iothread->ctx is set to NULL, aio_context_unref triggers the assertion:
> g_source_unref: assertion 'source != NULL' failed.
> The patch fixes it.
> 
> Signed-off-by: Lin Ma <lma@suse.com>
> ---
>  iothread.c | 3 +++
>  1 file changed, 3 insertions(+)

Thanks, applied to my block tree:
https://github.com/stefanha/qemu/commits/block

Stefan