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Date: Sun, 09 Oct 2011 15:13:35 +0200
From: Miroslav Lachman <000.fbsd@quip.cz>
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Cc: freebsd-current@freebsd.org, Ivan Voras <ivoras@freebsd.org>,
	freebsd-geom@freebsd.org
Subject: Re: RFC: Project geom-events
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Lev Serebryakov wrote:
> Hello, Miroslav.
> You wrote 6 октября 2011 г., 16:59:19:

[...]

>> The current state is simply wrong, because user can do something what
>> cannot work and is not documented anywhere.
>    It is Ok in UNIX way, in general. You should be able to shoot your
>   leg, it is good :)

I am sorry for my late reply.
Foot shooting is OK, if somebody wants to shoot his foot, but I don't 
want to shoot my foot if I am aiming at my head :)

>    But if geom_label doesn't reduce its provider to count its own
>   metadata, it looks like a bug!

As Ivan Voras explained, it is not a bug, it is just a matter of mixing 
two things thant can't coexist together. So the problem is that it is 
not mentioned anywhere in the FreeBSD docs. (Thank you Ivan for your 
explanation!)
And as somebody else already mentioned in this thread, it should be 
documented in manpages and Handbook and gpart should show warning 
message if user is trying to put GPT on non real disk devices.

As is mentioned in the thread "Memstick image differences between 8.x 
and 9.x", the GPT brings more problems by requirement of second table at 
the end of the device (so disk image cannot be easily written by dd on 
bigger disk)