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From: Roland Dreier <rdreier@cisco.com>
To: Stefan Roscher <ossrosch@linux.vnet.ibm.com>
Subject: Re: [ewg] [PATCH] IB/ehca: Protect QP against destroying until all
	async events for it are handled.
References: <200805071319.37164.ossrosch@linux.vnet.ibm.com>
Date: Wed, 07 May 2008 08:32:03 -0700
In-Reply-To: <200805071319.37164.ossrosch@linux.vnet.ibm.com> (Stefan
	Roscher's message of "Wed, 7 May 2008 13:19:35 +0200")
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Cc: LinuxPPC-Dev <linuxppc-dev@ozlabs.org>, fenkes@de.ibm.com,
	LKML <linux-kernel@vger.kernel.org>, raisch@de.ibm.com,
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 > We are not sure if this should be fixed in the driver or in uverbs itself.
 > Roland, what's your opinion about this?

Would be nice to be able to fix it in uverbs but I don't see how.  In
particular a kernel consumer has to have the same guarantee that no
async events will come in after destroy QP returns.  And I don't see any
way generic code can provide a guarantee about what low-level driver
code may do internally.