From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qv1-f50.google.com (mail-qv1-f50.google.com [209.85.219.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4216915E83 for ; Sun, 23 Jun 2024 08:18:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.50 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719130718; cv=none; b=UsbdDQtNts5vwaACQYKcAWVpgetGLdmaSk4C1DxdQyijzf5gJCS7VxMahV3VCgd8Nnwevi2z+/QS/ezsMFdDoewHcu2VUHC6l3G/yk6uTTAsnivLqOI0WjV/boYh/miTAyhye4XTZ0MFtV3L6akhaFzCgucId6h3B3BP+EZIqpI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719130718; c=relaxed/simple; bh=L7/GcWS21G16kMIr4Rzh73cWYISjZBxjNnHHyKG51rA=; h=Date:From:To:Cc:Message-ID:In-Reply-To:References:Subject: Mime-Version:Content-Type; b=XrY2exHsZFSH8FjMSpKWFMsJ0VymqFnqcfyutSAJM3OVlA/yjGZh3zd8zaPHwMWslTU2Qi3ttAUTKDQORGHDODQeW/3rkf1i9Dn6Mufj3zfcfMymy8r8CN8EoihLm8XTOgo5lx/Jqv6qVVuB7zjR5nVoVmXCNYyrx5eFLD8AJFU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=m5EueZIU; arc=none smtp.client-ip=209.85.219.50 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="m5EueZIU" Received: by mail-qv1-f50.google.com with SMTP id 6a1803df08f44-6ad86f3cc34so15584056d6.1 for ; Sun, 23 Jun 2024 01:18:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1719130716; x=1719735516; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=QfS9kQF98h4Kpv62+gbOTX+SlATEv6FSmMirHiclb+g=; b=m5EueZIUPELEW3+YlMMkEhaBx83a3Jub/5wTTWp63g+mbyrEjW+T7WsoboQiyu3BpJ 914rGRo18zoliH8Os9ZsEigH7tdlOIJ1wWjzLHouhPtpjK9wPvdT4HhWMu4ha0hGCX8w uOoko9q69+aoncnWpUxiFUsM/yQ18VRaZmtLmj1ZWC+njIBvN9kdF6NgShcv+xhP+UWr NYyei2YsxrAa/NPOgHfJCw4LV5aemG2D9m1yJepCPH+d3dP5wuHbnqKG7Qoj1UcGSosA BUiw01cje3C/B46wdO8Glmvsz0AOeYTqKPSJLMsUoRXsB52yHD+M5BVQ30ID4NuYIs1J rjSg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1719130716; x=1719735516; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=QfS9kQF98h4Kpv62+gbOTX+SlATEv6FSmMirHiclb+g=; b=mwKipyiHEJjKBB3bCKaJB6zTYMzS2VU3k0U6yRqbq3H8zIerWMNc72PDZlmmlssldK QM2a8+EODR7fsh9BoWlwQNHzW79K9CXZcvnsNhpEq0+AaTyPCTQTiLuVoKnqDTkjTfhk 0OLdT+xFmq5597ReznvFcHRAgz3GCH0hrHghItTPf0r+/oKdGdvgiHsokT+4yUPWyYQY w39lxc/3BHwoa3wCyMZU7a0RNOdMTf3JfpWTnfY4k3Jz7RxgGYe/bGePCHSES4Oruuv0 2T98VyigpTnKmBCUx76FtXCEcQu0vj4B1XvaIP42C9b+4YUx+c60Y6zYk3qOFInF0wgu O+pw== X-Forwarded-Encrypted: i=1; AJvYcCVP1seXw65Okjdh/2MgF5xc+xWjdcPEO2WM2hMGOY1zXl6ehz+nn4ptT+y2OAH6VHDrznJdP+aCoAuZgLWYlI5ftnauHCzq X-Gm-Message-State: AOJu0YyGtRisYqmEWSzqLpOB41P/K8OFqLryBaRIqwslhKemuwDQBIE0 Wxe8WEGCtJZ9gNmD/zaYVWHDjjW6ZXgpFTcBpIB1Cmr1Kmvd9cDj X-Google-Smtp-Source: AGHT+IGqgXi1aNJ1PKoaCXA6SED3DDm396EdJfGp1ppfQA0T+x4/RHNXfRJTTiMqHv2n9QnFMwsiGg== X-Received: by 2002:a05:6214:3005:b0:6b4:fdcd:1604 with SMTP id 6a1803df08f44-6b53bff0eadmr26188626d6.62.1719130715952; Sun, 23 Jun 2024 01:18:35 -0700 (PDT) Received: from localhost (56.148.86.34.bc.googleusercontent.com. [34.86.148.56]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-6b5295df066sm16183396d6.64.2024.06.23.01.18.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 23 Jun 2024 01:18:35 -0700 (PDT) Date: Sun, 23 Jun 2024 04:18:35 -0400 From: Willem de Bruijn To: Jakub Sitnicki , netdev@vger.kernel.org Cc: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Willem de Bruijn , kernel-team@cloudflare.com Message-ID: <6677da5b3c52e_334d34294dd@willemb.c.googlers.com.notmuch> In-Reply-To: <20240622-linux-udpgso-v1-0-d2344157ab2a@cloudflare.com> References: <20240622-linux-udpgso-v1-0-d2344157ab2a@cloudflare.com> Subject: Re: [PATCH net 0/2] Lift UDP_SEGMENT restriction for egress via device w/o csum offload Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Jakub Sitnicki wrote: > This is a follow-up to an earlier question [1] if we can make UDP GSO work with > any egress device, even those with no checksum offload capability. That's the > default setup for TUN/TAP. > > I leave it to the maintainers to decide if it qualifies as a fix. We plan to > backport it to our v6.6 either way, hence the submission to -net. > > [1] https://lore.kernel.org/netdev/87jzqsld6q.fsf@cloudflare.com/ Agreed with the change to allow UDP_SEGMENT to work regardless of device capabilities. In my opinion this is a new feature with sufficient risk of unintended side effects to be net-next material. Maybe worth recording in patch 1 the reason for the original check: that UDP_SEGMENT with software checksumming in the GSO stack may be a regression vs copy_and_checksum in the send syscall. > > Signed-off-by: Jakub Sitnicki > --- > Jakub Sitnicki (2): > udp: Allow GSO transmit from devices with no checksum offload > selftests/net: Add test coverage for UDP GSO software fallback > > net/ipv4/udp.c | 3 +-- > net/ipv4/udp_offload.c | 8 +++++++ > net/ipv6/udp.c | 3 +-- > tools/testing/selftests/net/udpgso.c | 15 +++++++++--- > tools/testing/selftests/net/udpgso.sh | 43 +++++++++++++++++++++++++++++++++++ > 5 files changed, 65 insertions(+), 7 deletions(-) >