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Message-ID: <012e78aa-fd4a-35c7-5405-752bcd675449@nvidia.com>
Date:   Thu, 3 Feb 2022 13:13:51 -0800
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Subject: Re: [PATCH v3 1/4] mm: Fix invalid page pointer returned with
 FOLL_PIN gups
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To:     Christoph Hellwig <hch@infradead.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Peter Xu <peterx@redhat.com>, Jason Gunthorpe <jgg@ziepe.ca>,
        David Hildenbrand <david@redhat.com>,
        Lukas Bulwahn <lukas.bulwahn@gmail.com>,
        Jan Kara <jack@suse.cz>,
        Claudio Imbrenda <imbrenda@linux.ibm.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Alex Williamson <alex.williamson@redhat.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>, linux-mm@kvack.org
References: <20220203093232.572380-1-jhubbard@nvidia.com>
 <20220203093232.572380-2-jhubbard@nvidia.com>
 <YfvgC5Y9mTb3vKlV@infradead.org>
From:   John Hubbard <jhubbard@nvidia.com>
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On 2/3/22 06:00, Christoph Hellwig wrote:
> On Thu, Feb 03, 2022 at 01:32:29AM -0800, John Hubbard wrote:
>> From: Peter Xu <peterx@redhat.com>
>>
>> Alex reported invalid page pointer returned with pin_user_pages_remote() from
>> vfio after upstream commit 4b6c33b32296 ("vfio/type1: Prepare for batched
>> pinning with struct vfio_batch").  This problem breaks NVIDIA vfio mdev.
> 
> There still isn't any nvidia vfio mdev driver in the tree, so this
> changelog stilldoesn't make sense.

I'll remove that last sentence (and put in a tiny note that I'm scribbling
on Peter's commit description a little bit more), in order to avoid any
references to out of tree things.

thanks,
-- 
John Hubbard
NVIDIA