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Message-ID: <54CED08C.2080501@cn.fujitsu.com>
Date: Mon, 2 Feb 2015 09:19:08 +0800
From: Wen Congyang <wency@cn.fujitsu.com>
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Subject: Re: [Qemu-devel] [PATCH] quorum: don't share qiov
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To: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-devl <qemu-devel@nongnu.org>, Stefan Hajnoczi <stefanha@redhat.com>

On 01/30/2015 09:39 PM, Kevin Wolf wrote:
> Am 30.01.2015 um 09:07 hat Wen Congyang geschrieben:
>> If the child touches qiov->iov, it will cause unexpected results.
>>
>> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
> 
> Any specific child you're thinking of?
> 
> I think children are not supposed to modify their qiov (which would also
> fail for init_external qiovs). Perhaps we should have made it const.

NBD client. The qiov will be modified in iov_send_recv():
nbd_co_writev()
    nbd_client_session_co_writev()
        nbd_co_writev_1()
            nbd_co_send_request()
                qemu_co_sendv()
                    qemu_co_sendv_recvv()
                        iov_send_recv()

Thanks
Wen Congyang

> 
> Kevin
>