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Date: Fri, 15 May 2015 17:14:28 +0800
From: Fam Zheng <famz@redhat.com>
Message-ID: <20150515091428.GA17355@ad.nay.redhat.com>
References: <cover.1431523498.git.berto@igalia.com>
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Subject: Re: [Qemu-devel] [PATCH 04/11] block: Support streaming to an
 intermediate layer
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To: Alberto Garcia <berto@igalia.com>
Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org

On Fri, 05/15 11:04, Alberto Garcia wrote:
> On Fri 15 May 2015 04:33:19 AM CEST, Fam Zheng wrote:
> 
> >> +    /* Make sure that the image is opened in read-write mode */
> >> +    orig_bs_flags = bdrv_get_flags(bs);
> >> +    if (!(orig_bs_flags & BDRV_O_RDWR)) {
> >> +        if (bdrv_reopen(bs, orig_bs_flags | BDRV_O_RDWR, errp) != 0) {
> >
> > I don't think all bdrv_reopen implementation will guarantee to set errp
> > on error :(. For example:
> >
> >     static int qcow2_reopen_prepare(BDRVReopenState *state,
> >                                     BlockReopenQueue *queue, Error **errp)
> >     {
> 
> bdrv_reopen_prepare() already sets a generic error if the implementation
> (qcow2_reopen_prepare() in this case) doesn't provide one:
> 
>     ret = drv->bdrv_reopen_prepare(reopen_state, queue, &local_err);
>     if (ret) {
>         if (local_err != NULL) {
>             error_propagate(errp, local_err);
>         } else {
>             error_setg(errp, "failed while preparing to reopen image '%s'",
>                        reopen_state->bs->filename);
>         }
>         goto error;
>     }
> 

You're right, I missed that. So,

Reviewed-by: Fam Zheng <famz@redhat.com>