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Tsirkin" To: Sergio Lopez Cc: virtio-comment@lists.linux.dev, dmitry.osipenko@collabora.com, parav@nvidia.com Subject: Re: [PATCH v2 1/3] shared-mem: introduce page alignment restrictions Message-ID: <20250331121538-mutt-send-email-mst@kernel.org> References: <20250331150548.50595-1-slp@redhat.com> <20250331150548.50595-2-slp@redhat.com> Precedence: bulk X-Mailing-List: virtio-comment@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <20250331150548.50595-2-slp@redhat.com> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 55zVBW3Kd9ROIAhTy5NIm6DY6CiZu-6x5rdtpXdGj2U_1743437775 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Mar 31, 2025 at 11:05:46AM -0400, Sergio Lopez wrote: > Add a subsection for page alignment restrictions. > > Signed-off-by: Sergio Lopez > --- > shared-mem.tex | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/shared-mem.tex b/shared-mem.tex > index 6e6f6c4..2021083 100644 > --- a/shared-mem.tex > +++ b/shared-mem.tex > @@ -34,6 +34,12 @@ \subsection{Addressing within regions}\label{sec:Basic Facilities of a Virtio De > The \field{shmid} may be explicit or may be inferred from the > context of the reference. > > +\subsection{Page alignment restrictions}\label{sec:Basic Facilities of a Virtio Device / Shared Memory Regions / Page alignment restrictions} > + > +When requesting the device to map memory into a shared memory region > +the driver MUST obtain the page size information from the transport > +and honor the page alignment constrains derived from that page size. > + will make existing drivers autmatically incompliant with new devices. we generally avoid things like this. > \devicenormative{\subsection}{Shared Memory Regions}{Basic Facilities of a Virtio > Device / Shared Memory Regions} > Shared memory regions MUST NOT expose shared memory regions which > -- > 2.49.0