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Date:   Thu, 11 Feb 2021 07:55:10 +0000
From:   Christoph Hellwig <hch@infradead.org>
To:     Jason Gunthorpe <jgg@ziepe.ca>
Cc:     John Hubbard <jhubbard@nvidia.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Alistair Popple <apopple@nvidia.com>,
        Linux MM <linux-mm@kvack.org>,
        Nouveau Dev <nouveau@lists.freedesktop.org>,
        Ben Skeggs <bskeggs@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linux Doc Mailing List <linux-doc@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        kvm-ppc@vger.kernel.org,
        dri-devel <dri-devel@lists.freedesktop.org>,
        Ralph Campbell <rcampbell@nvidia.com>,
        Jerome Glisse <jglisse@redhat.com>
Subject: Re: [PATCH 0/9] Add support for SVM atomics in Nouveau
Message-ID: <20210211075510.GA2368090@infradead.org>
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On Wed, Feb 10, 2021 at 01:59:13PM -0400, Jason Gunthorpe wrote:
> Really what you want to do here is leave the CPU page in the VMA and
> the page tables where it started and deny CPU access to the page. Then
> all the proper machinery will continue to work.
> 
> IMHO "migration" is the wrong idea if the data isn't actually moving.

Agreed.