linux-kernel - Re: [PATCH v3] io: add io

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <aT4KDZSWLMlKwusl@nvidia.com>
Date: Sat, 13 Dec 2025 20:51:25 -0400
From: Jason Gunthorpe <jgg@...dia.com>
To: Boris Brezillon <boris.brezillon@...labora.com>
Cc: Alice Ryhl <aliceryhl@...gle.com>, Miguel Ojeda <ojeda@...nel.org>,
	Will Deacon <will@...nel.org>,
	Daniel Almeida <daniel.almeida@...labora.com>,
	Boqun Feng <boqun.feng@...il.com>, Gary Guo <gary@...yguo.net>,
	Björn Roy Baron <bjorn3_gh@...tonmail.com>,
	Benno Lossin <lossin@...nel.org>,
	Andreas Hindborg <a.hindborg@...nel.org>,
	Trevor Gross <tmgross@...ch.edu>,
	Danilo Krummrich <dakr@...nel.org>, Joerg Roedel <joro@...tes.org>,
	Robin Murphy <robin.murphy@....com>,
	Lorenzo Stoakes <lorenzo.stoakes@...cle.com>,
	"Liam R. Howlett" <Liam.Howlett@...cle.com>,
	Asahi Lina <lina+kernel@...hilina.net>,
	linux-kernel@...r.kernel.org, rust-for-linux@...r.kernel.org,
	iommu@...ts.linux.dev, linux-mm@...ck.org,
	Alistair Popple <apopple@...dia.com>
Subject: Re: [PATCH v3] io: add io_pgtable abstraction

On Fri, Dec 12, 2025 at 10:41:05AM +0100, Boris Brezillon wrote:

> > Then you can think about what is ideal for GPU and consider what the
> > work would be like. My uneducated feeling is with gpuvm trying to be
> > common code it could also have gpuvm provide shared common code that
> > directly builds page tables in CPU memory using the above framework.
> 
> So, gpuvm is one level up (it doesn't deal at all with any HW
> representation), but I guess we could provide helpers for UMA-GPUs,
> where preparing the page table on the CPU is a thing, and it could be
> that MSM would be interested in using those helpers too.

You can make it work like the iommu does where gpuvm gets a "gpu
domain" from the driver that is created by using the common code from
gpuvm. Then most of the code is common.

I think something could be built that works with the framebuffer
resident page tables too if they are being accessed over mmio.

Jason