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Date:   Wed, 20 Sep 2023 09:02:22 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     <ankita@nvidia.com>
Cc:     <jgg@nvidia.com>, <alex.williamson@redhat.com>,
        <tony.luck@intel.com>, <bp@alien8.de>, <naoya.horiguchi@nec.com>,
        <linmiaohe@huawei.com>, <aniketa@nvidia.com>, <cjia@nvidia.com>,
        <kwankhede@nvidia.com>, <targupta@nvidia.com>, <vsethi@nvidia.com>,
        <acurrid@nvidia.com>, <anuaggarwal@nvidia.com>,
        <linux-kernel@vger.kernel.org>, <linux-mm@kvack.org>,
        <linux-edac@vger.kernel.org>, <kvm@vger.kernel.org>
Subject: Re: [PATCH v1 0/4] mm: Implement ECC handling for pfn with no
 struct page
Message-Id: <20230920090222.580f2b3ca43f21f752c10e0a@linux-foundation.org>
In-Reply-To: <20230920140210.12663-1-ankita@nvidia.com>
References: <20230920140210.12663-1-ankita@nvidia.com>
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On Wed, 20 Sep 2023 19:32:06 +0530 <ankita@nvidia.com> wrote:

> The kernel MM currently handles ECC errors / poison only on memory page
> backed by struct page. As part of [1], the nvgrace-gpu-vfio-pci module
> maps the device memory to user VA (Qemu) using remap_pfn_range without
> being added to the kernel. These pages are not backed by struct page.

Are you able to identify any other drivers which can (or will) use
this?  Or is it likely that this feature will only ever be for
nvgrace-gpu-vfio-pci?