Re: [Qemu-block] [PATCH v6 2/2] qemu-img: Document --force-share / -U

[Kashyap Chamarthy]

On Tue, Jan 30, 2018 at 08:23:50AM -0600, Eric Blake wrote:
> On 01/30/2018 12:34 AM, Fam Zheng wrote:

[...]

> > +If specified, @code{qemu-img} will open the image in shared mode, allowing
> > +concurrent writers. For example, this can be used to get the image 
> > information
> 
> Actually, we only permit one writer at a time.  Would it be better to
> say "allowing a concurrent writer"?

Definitely worth rewording.  Otherwise the two sentences:

    "If specified, @code{qemu-img} will open the image in shared mode,
     allowing concurrent writers."

    "This option is only allowed when opening images in read-only mode."

are at odds with each other --- it says "concurrent writers" are
allowed, BUT "allowed only when opening images in 'read-only' mode".

> > +(with 'info' subcommand) when the image is used by a running guest.  Note 
> > that
> > +this could produce inconsistent results because of concurrent metadata 
> > changes,
> > +etc. This option is only allowed when opening images in read-only mode.
> 
> After all, we are stating that this process (which must be read-only,
> because we can't have two writers at once) is permitting some other
> process to be the concurrent writer (but not multiple processes to be
> concurrent writers)

Precisely.  So it's worth being clearer.

With the rewording suggested by Eric:

    Reviewed-by: Kashyap Chamarthy <address@hidden>

-- 
/kashyap