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Date:   Wed, 4 May 2022 13:53:38 +0200
From:   Joerg Roedel <joro@8bytes.org>
To:     Robin Murphy <robin.murphy@arm.com>
Cc:     Jan Stancek <jstancek@redhat.com>,
        Lu Baolu <baolu.lu@linux.intel.com>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Christoph Hellwig <hch@infradead.org>,
        Ben Skeggs <bskeggs@redhat.com>,
        Kevin Tian <kevin.tian@intel.com>,
        Ashok Raj <ashok.raj@intel.com>, Will Deacon <will@kernel.org>,
        Alex Williamson <alex.williamson@redhat.com>,
        Eric Auger <eric.auger@redhat.com>,
        Liu Yi L <yi.l.liu@intel.com>,
        Jacob jun Pan <jacob.jun.pan@intel.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        Thierry Reding <thierry.reding@gmail.com>,
        Jonathan Hunter <jonathanh@nvidia.com>,
        iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
        Christoph Hellwig <hch@lst.de>, bgoncalv@redhat.com
Subject: Re: [bug] NULL pointer deref after 3f6634d997db ("iommu: Use right
 way to retrieve iommu_ops")
Message-ID: <YnJpQiEJWNjyOyji@8bytes.org>
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 <20220504075356.GA2361844@janakin.usersys.redhat.com>
 <8d6c30e0-dcf7-56f8-c44b-2d8bdb1dc04c@arm.com>
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Hi Robin,

On Wed, May 04, 2022 at 12:14:07PM +0100, Robin Murphy wrote:
> Oof, this can probably be hit with vfio-noiommu too, and by the look of
> things, `echo auto > /sys/kernel/iommu_groups/0/type` would likely blow
> up as well. Does the patch below work for you?

Thanks for the quick patch! I am delaying to send iommu-fixes upstream
for now in the hope the fix can make it into the branch asap. Please
send it out as a separate patch as soon as it is successfully tested.

Regards,

	Joerg