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Date: Wed, 7 May 2025 14:50:18 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Pantelis Antoniou <p.antoniou@partner.samsung.com>
Cc: <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>, Artem Krupotkin
 <artem.k@samsung.com>, Charles Briere <c.briere@samsung.com>, Wade
 Farnsworth <wade.farnsworth@siemens.com>
Subject: Re: [PATCH 0/1] Fix zero copy I/O on __get_user_pages allocated
 pages
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On Wed, 7 May 2025 10:41:04 -0500 Pantelis Antoniou <p.antoniou@partner.samsung.com> wrote:

> Updates to network filesystems enabled zero copy I/O by using the
> netfslib common accessors.

Updates by whom?  Are all the people who need to know about this being
cc'ed here?

> One example of that is the 9p filesystem which is commonly used in qemu
> based setups for sharing files with the host.
> 
> In our emulation environment we have noticed failing writes when performing
> I/O from a userspace mapped DRM GEM buffer object.
> The platform does not use VRAM, all graphics memory is regular DRAM memory,
> allocated via __get_free_pages

We should identify which kernel version(s) should be patched, please. 
6.16-rc1?  6.15?  -stable?

I often make these decisions but in this case I have far too little
information to be able to do that.

Thanks.