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Tsirkin" To: Jason Gunthorpe Cc: Cindy Lu , jasowang@redhat.com, yi.l.liu@intel.com, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org Subject: Re: [RFC v1 0/8] vhost-vdpa: add support for iommufd Message-ID: <20231107105718-mutt-send-email-mst@kernel.org> References: <20231103171641.1703146-1-lulu@redhat.com> <20231107022847-mutt-send-email-mst@kernel.org> <20231107124902.GJ4488@nvidia.com> <20231107094818-mutt-send-email-mst@kernel.org> <20231107154848.GP4488@nvidia.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231107154848.GP4488@nvidia.com> On Tue, Nov 07, 2023 at 11:48:48AM -0400, Jason Gunthorpe wrote: > On Tue, Nov 07, 2023 at 09:55:26AM -0500, Michael S. Tsirkin wrote: > > On Tue, Nov 07, 2023 at 08:49:02AM -0400, Jason Gunthorpe wrote: > > > IMHO, this patch series needs to spend more time internally to Red Hat > > > before it is presented to the community. > > > > Just to add an example why I think this "internal review" is a bad idea > > I seem to recall that someone internal to nvidia at some point > > attempted to implement this already. The only output from that > > work we have is that "it's tough" - no pointers to what's tough, > > no code to study even as a bad path to follow. > > And while Red Hat might be big, the virt team is rather smaller. > > I don't think Nicolin got to a presentable code point. > > But you can start to see the issues even in this series, like > simulator is complicated. mlx5 is complicated. Deciding to omit those > is one path. Come with a proposal and justification to take it out, > not a patch with an unexplained #ifdef. Right. Simulator I don't think we need to support, or at least not necessarily to get this merged - it does not really benefit from any iommufd features.