From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 716F9606A31C for ; Tue, 20 Oct 2026 19:19:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=A7w0gEdO Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9BB1010E0F8; Tue, 20 Oct 2026 19:19:07 +0000 (UTC) Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by gabe.freedesktop.org (Postfix) with ESMTPS id 935F610E0F8 for ; Tue, 20 Oct 2026 19:19:01 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id C8005601FE; Tue, 20 Oct 2026 19:19:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 921281F000C9; Tue, 20 Oct 2026 19:18:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792523940; bh=o+qYngWD3VtHRYJROR8r2QEagYzTVh9jUdoxhwafRww=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=A7w0gEdOvYzmk0vkW1JwU8bkYmH1HgaxOPga0sFNm0yLcYM4qvuuthmiN2t9Vfdoz Cvd4nrhYU5g2767tUif4Olx3uzuA/n46c9VtZTpU9WVxwL3YptLYYmWfvH3KroQ5Dv lWcBo5Qsj0pQHd7fBmqd0z0hPK+h7fEvL4kUx4Cf4987ztpjXd5CyKl5iAy+0FURRY 9bvyzOZvLD2ZovXoR9m02gJzdFd6jpTAWE45BDZ1zpEeJsVqIGwY2blTooVEy7m6e5 MEg/4Um77dGmgbveH57cGzYzZiXaO9DwLdLyfo9Y4AkHpPdJWnWc5E/IUoMft3kNva 1dzazHcVxQ7kg== Date: Tue, 20 Oct 2026 12:18:58 -0700 From: Jakub Kicinski To: Mina Almasry Cc: Pavel Begunkov , David Wei , Stanislav Fomichev , Taehee Yoo , Paolo Abeni , Kaiyuan Zhang , Bobby Eshleman , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, Andrew Lunn , "David S. Miller" , Eric Dumazet , Jesper Dangaard Brouer , Ilias Apalodimas , Simon Horman , Shuah Khan , Sumit Semwal , "Christian =?UTF-8?B?S8O2bmln?=" , Dragos Tatulea , Nikolay Aleksandrov , Daniel Borkmann , Tariq Toukan , Kaifeng Wang Subject: Re: [PATCH net v4 3/4] netdevsim: support devmem RX and TX bindings Message-ID: <20261020121858.3b9107c5@kernel.org> In-Reply-To: <20261015163915.1166043-4-almasrymina@google.com> References: <20261015163915.1166043-1-almasrymina@google.com> <20261015163915.1166043-4-almasrymina@google.com> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "dri-devel" X-Spam-Status: No, score=-6.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Thu, 15 Oct 2026 16:39:14 +0000 Mina Almasry wrote: > Set a 64-bit DMA mask on nsim_bus_dev, enable NETMEM_TX_DMA on the > netdevsim net_device, and configure page_pool instances with > PP_FLAG_ALLOW_UNREADABLE_NETMEM and queue_idx, plus PP_FLAG_DMA_MAP | > PP_FLAG_DMA_SYNC_DEV when CONFIG_HAS_DMA is set, so devmem bind-rx and > bind-tx netlink operations can be tested against netdevsim in software > selftests. Slightly worried this will bring a bunch of maintenance burden and "bugs" in netdevsim. IOW that this will be more pain than gain.