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Date: Thu, 25 Oct 2012 11:54:08 +0300
From: Andriy Gapon <avg@FreeBSD.org>
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To: Poul-Henning Kamp <phk@phk.freebsd.dk>
Subject: Re: geom access method and g_topology_lock
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on 25/10/2012 11:41 Poul-Henning Kamp said the following:
> --------
> In message <5088FA15.30205@FreeBSD.org>, Andriy Gapon writes:
> 
>> Both pieces look sane and non-racy (because of g_topology_assert) until we allow
>> g_access (some geom access method, rather) to drop the topology lock.
> 
> You lost me there.
> 
> g_access() cannot do its job without holding the topology lock.
> 
> 

Will it help if I repeat my original questions:

Is that bad if a geom's access method drops and re-acquires g_topology_lock
while doing some internal stuff?
Is that allowed at all?

To clarify, if that's needed, by "geom's access method" I meant the 'access'
member with g_access_t type in struct g_geom.

-- 
Andriy Gapon