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Date: Tue, 23 Dec 2025 21:14:40 +0100
Message-Id: <DF5VE17B8HTA.1XSONUJ4XOFCY@kernel.org>
From: "Danilo Krummrich" <dakr@kernel.org>
Subject: Re: [PATCH v8] rust: Return Option from page_align and ensure no
 usize overflow
Cc: <acourbot@nvidia.com>, "Brendan Shephard" <bshephar@bne-home.net>,
 <miguel.ojeda.sandonis@gmail.com>, <daniel.almeida@collabora.com>,
 <rust-for-linux@vger.kernel.org>
To: <aliceryhl@google.com>
References: <20251223055647.9761-1-bshephar@bne-home.net>
In-Reply-To: <20251223055647.9761-1-bshephar@bne-home.net>

On Tue Dec 23, 2025 at 6:56 AM CET, Brendan Shephard wrote:
> Change `page_align()` to return `Option<usize>` to allow validation
> of the provided `addr` value. This ensures that any value that is
> within one `PAGE_SIZE` of `usize::MAX` will not panic, and instead
> returns `None` to indicate overflow.
>
> Signed-off-by: Brendan Shephard <bshephar@bne-home.net>
> Reviewed-by: Alice Ryhl <aliceryhl@google.com>
> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
> Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>

Alice, unless you have any concerns I'd take this through the drm-rust tree=
, so
I can pick up the corresponding nova-drm patch as well.