From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joerg Roedel <joro@8bytes.org>
Subject: Re: kvm PCI assignment & VFIO ramblings
Date: Tue, 30 Aug 2011 18:14:33 +0200
Message-ID: <20110830161433.GC5203@8bytes.org>
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Cc: "Roedel, Joerg" <Joerg.Roedel@amd.com>,
	Alexander Graf <agraf@suse.de>,
	Alexey Kardashevskiy <aik@au1.ibm.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	Paul Mackerras <pmac@au1.ibm.com>,
	qemu-devel <qemu-devel@nongnu.org>,
	iommu <iommu@lists.linux-foundation.org>,
	chrisw <chrisw@sous-sol.org>,
	Alex Williamson <alex.williamson@redhat.com>,
	Anthony Liguori <anthony@codemonkey.ws>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
	linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
	"benve@cisco.com" <benve@cisco.com>
To: Avi Kivity <avi@redhat.com>
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On Sun, Aug 28, 2011 at 05:04:32PM +0300, Avi Kivity wrote:
> On 08/28/2011 04:56 PM, Joerg Roedel wrote:

>> This can't be secured by a lock, because it introduces potential
>> A->B<-->B->A lock problem when two processes try to take each others mm.
>> It could probably be solved by a task->real_mm pointer, havn't thought
>> about this yet...
>>
>
> Or a workqueue -  you get a kernel thread context with a bit of boilerplate.

Right, a workqueue might do the trick. We'll evaluate that. Thanks for
the idea :)

	Joerg