From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=pass header.oldest-pass=0 smtp.remote-ip=209.85.208.47 ARC-Seal: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=pass; t=1792563469; b=dLZ2JpfxVk/u6NgrSDJeN1AAEaLZp9o21CxihFkrXFKu/RQJGL1bWsu+Q2+xOzcGmGx2 zUSJyHz/jPuNLdg1S6GNSkPPNEGiTkH2rB5ekAInGcu2/uGN9kOn9cv0fs3YwoDe+HlWv LgFFyr/qkriQggJpVIZHonf31NBaCnlzqnDoXIvo1YbqMfiAtYLkIF5wcRHr6XOl02Sbc ABM+aBJ2i74qNJ+kFmC0VQOHopuhcc56W4BlNiK7deyq9xfs8Tjj54NLoyRwcq4kCOmDi JFabEwzFSTLnLJev60FQgg7jrSpsbY18Dh7M9NswNI5uMQUYdYF9JkiZyl26evlakaA== ARC-Message-Signature: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792563469; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received: MIME-Version:References:In-Reply-To:From:Date:X-Gm-Features: Message-ID:Subject:To:Cc:Content-Type:Content-Transfer-Encoding; bh=OpMUSfXjYdpw9tHtxpMBZ2ptmbz/1TA55D+obf0dVY0=; b=jbveICXuKFqha1iIC62wl25P0InMplggjeSLmOeD18dr1kdj/2dP/mzzDESDozLiLWoT WhewXVgKVVbEe8dsJ9tga0BGGUVk2lmwBB6C7Qe532qu+ZYqNg4KdO/ILV2UlS618OOHf JdojADGoiT5pelFKPzs2N3wO65lvCQ59GE0rduiFNHhXV4ly+l3fdzvpU6xydYrRIS0/E O0UC/ajf3i0hWyoJcL92oudmB72WeG1kxjfrY+ORA6GbyM7GaFYJFGjlxQ2cgLWiKcpXe 5FEoz9jjGTY4QaT8+ZTTb4fm/rHsvToUp6utC1o0CpU3Mo0yH6BKG4TjKetdM9QBEoQ== ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass header.from=google.com; spf=pass smtp.mailfrom=google.com; dkim=pass header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20251104 header.b=pQIPJhuw; arc=pass header.oldest-pass=0 smtp.remote-ip=209.85.208.47 Received: from mail-ed1-f47.google.com (mail-ed1-f47.google.com [209.85.208.47]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EA9A5606A322 for ; Wed, 21 Oct 2026 06:17:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org EA9A5606A322 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20251104 header.b=pQIPJhuw Received: by mail-ed1-f47.google.com with SMTP id 4fb4d7f45d1cf-6b1b12de661so7540a12.0 for ; Tue, 20 Oct 2026 23:17:48 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1792563467; cv=none; d=google.com; s=arc-20260327; b=JScJWgSdHHb7MPTC4SeM964wi2u/5lYm9l1uax46IqpQlX55FpnLHQkpGXf2Z5HIr1 JgiNND7J16IKE8g6ei952O97UF6Jvto5ftFRLgLa36Wv6x61jzYeISIRBeT3FQxXWX3r q0HwnUeeGH0qF9FftcGTBS9DcLp2QWGECzWbo7QRdilQh1u2m7JywVFi5TvAJJ1uL2Nt ZtFPPAJgtPrbsztIsYqksHUI0S9Yu7veV6bQsB26/fzPOe9Ly9Jtx0RlXyHTHnfctjLl rhewwYmn0+R4IcR5IEFgAPSYYlPqYErK8P9vt8bEei83+2jBYnAdSLisUbUZWi+e3qml xhUQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20260327; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:dkim-signature; bh=OpMUSfXjYdpw9tHtxpMBZ2ptmbz/1TA55D+obf0dVY0=; fh=2Up3HvTKRb6jDabc+1vuDJH7gnBL3pEaIabsjzYLwXg=; b=mQ0E8KgnW8RT/ij/+pyhOY38Qd23Pfs9oGcDidye+h5yJt8RxZDb/UAq/eXPIEEPAR PuOsIAffCjaGH/RU6dk1/3N61+VoLGl32kIjLciMy90LONr/TkFxyA99GrJoH53Ucs2b dCtBhYOwCk3MXO9paGiSr0pxKrd/V0FE/Osl+H5QlrwP6TXAbKByvcfC/BDWO7BdEldD 8jHLiA2mD4cnsGpJ5tVryocgqoCpGbjmuO0Y09+k3oYzVTPXvnPBrn/JdY50moYojjM7 pCLqIwbgBuyRQstoK4fhGiBkyg6LLr48iCtjIHuxPL70uBxeVXOcibzKNb5bBlsnzRWw Pxdg==; darn=vger.kernel.org ARC-Authentication-Results: i=1; mx.google.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1792563467; x=1793168267; darn=vger.kernel.org; h=content-transfer-encoding:content-type:cc:to:subject:message-id :date:from:in-reply-to:references:mime-version:from:to:cc:subject :date:message-id:reply-to:content-type; bh=OpMUSfXjYdpw9tHtxpMBZ2ptmbz/1TA55D+obf0dVY0=; b=pQIPJhuwRgwitqjGA3ItWVLOGRQSBJ2UxZPYrPAWnSbOgQb7bum+xLkiJsThMZqhOH dwhP0Tb7gfDJbRLLmYO0L58nN/lbc0ijCbj7vD9/AsO9AN+96fT1k2yklolZXbSXuPwo LvDI+a8olKugTFENbi6HjsCC3zDMl6Iz1h6NBkZRClcTcPd8ggh/X4oK3qTp3lqZ6g+A 1/vCcb7V+C3SGzXl2pN5Qza6vN7p6/inIC4foXEFviRK7uLerabWIo3jtiqgZBXKVU0E 35IRXsTcGT6NK/j4Qt7Yug3jaRtwJPct+J6CNc9iCK/DHqCogYkMU/l3zqzSbvR0IHLw KzOQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1792563467; x=1793168267; h=content-transfer-encoding:content-type:cc:to:subject:message-id :date:from:in-reply-to:references:mime-version:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=OpMUSfXjYdpw9tHtxpMBZ2ptmbz/1TA55D+obf0dVY0=; b=u2RMPNcM6ayRrEwshVJ8NQeEDpaQzxUDj4aKtlhIa8tU63f5geFHvp/TqDZsTLUUTK sk3iMbKA/h3wZZ66GLYPFGdsiyD7KHVb5zQaFACrAkXQdbjS+W/aPVqQv2yfuyItzZ3q pzcaeNRjqp2J1aonwak5hGOZ5C+RZQL+VUV0VzYehXSkOzcvNTUhkBEFrzA2XvpUO+Gp EH7sIu0St0ay4l3lfteZefRqcuRxPni8owBMOlYWQP/2WUk/o0Zx5JLaMGWQ150WamEQ ++H9nEeZcLh3fSvaEUB99tPXLkeozP5Y/lSXHm+wyZhEfE2KBG4gf4rzRWx3i4I85jfu ou4w== X-Forwarded-Encrypted: i=1; AKwUvBxwq2FeTeeHQnPXiAn5lUtFlE8GZ7Dmz4zrLQ4JAgbU2vflqLpCll2eSDce/sKqLD4CRm9WnWQc3rlorZM=@vger.kernel.org X-Gm-Message-State: AFq9FYINw9C1qHni1RtfrXCVs/SrzPQ80ytxkzzGDsYKtL+kvkhYnvM8 HNvgk+hEWJGjpTbRD8IacXa51FBVh3J1oQGjUf/T83pGH4aKjnrJmvvT0jZeP7/g9hYhtGjL6IU AohO1aKTrs0p1/7MA+75UxW3t2oQcBC318MiA2YEm X-Gm-Gg: AYBFou1M6j6B2rAsOyXUmMMR9b9IW83EXBH8lMiyHcSuAecufzA4NvA6jNh3PUZMvyG eg23kFK79qZkFcOW8vAVVstefTCZCkc+vZ6Gn3PGbbL9rSZA9P/SUqKn7qZYWKOYLBWQa+MHAso AUj4pkeVQK3CM1tAzRkbOLOReHsmbL9RLaq6f9CIy4QEwnW4Uinjo6AR4pPW1rs6tQg2oPD4MeX PSklWnpwgOyMiOpt1QAh5eyzNGTM835tjBmvlRXl9pJn4RT8mSc9uf0rrdxkM2Ems2kgc+9OxhJ D4iVDmLUJ0wRNVxh8GG7PN13RxNAk+ImWIhdChDg8BuyEt7FKN6k6ugXGP+jaxiL4jNMkq0AM2O zT7dLqRXuZZmVSWiZKlp7iz9dJar33dGbuA== X-Received: by 2002:a05:6402:4050:20b0:6b1:bce6:1220 with SMTP id 4fb4d7f45d1cf-6b3e77153d8mr91222a12.12.1792563466679; Tue, 20 Oct 2026 23:17:46 -0700 (PDT) X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 References: <20261015163915.1166043-1-almasrymina@google.com> <20261015163915.1166043-4-almasrymina@google.com> <20261020121858.3b9107c5@kernel.org> In-Reply-To: <20261020121858.3b9107c5@kernel.org> From: Mina Almasry Date: Tue, 20 Oct 2026 23:17:34 -0700 X-Gm-Features: AclHuK9x4qWdNnjJvUjsI2EHUcAIAKj09plc1NcLTKxrSfCtCSi6D5JlUi63xuU Message-ID: Subject: Re: [PATCH net v4 3/4] netdevsim: support devmem RX and TX bindings To: Jakub Kicinski 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 , =?UTF-8?Q?Christian_K=C3=B6nig?= , Dragos Tatulea , Nikolay Aleksandrov , Daniel Borkmann , Tariq Toukan , Kaifeng Wang Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, Oct 20, 2026 at 12:19=E2=80=AFPM Jakub Kicinski w= rote: > > 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. I felt the same way when I noticed many reported bugs against this series because I didn't add proper support. But on the other hand the test coverage is nice, and maybe one day if we add enough devmem support in netdevsim we'll be able to fuzz the data path or something. Is there a way to get the best of both worlds? Like put a comment on top of netdevsim that this is test simulator device and any missing functionality and/or bugs in it should be medium criticality max or something? Or is it too much trouble and I should drop the netdevsim support and tests? -- Thanks, Mina