From owner-freebsd-net@freebsd.org Thu Mar 18 20:33:19 2021 Return-Path: Delivered-To: freebsd-net@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id F0EB65ABDF8 for ; Thu, 18 Mar 2021 20:33:19 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.nyi.freebsd.org (unknown [127.0.1.3]) by mx1.freebsd.org (Postfix) with ESMTP id 4F1dyR6Hz5z4kFs for ; Thu, 18 Mar 2021 20:33:19 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.nyi.freebsd.org (Postfix) id D81545ABF3E; Thu, 18 Mar 2021 20:33:19 +0000 (UTC) Delivered-To: net@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id D7D875ABEEE for ; Thu, 18 Mar 2021 20:33:19 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4F1dyR5j2rz4jxR for ; Thu, 18 Mar 2021 20:33:19 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id B6EA5152 for ; Thu, 18 Mar 2021 20:33:19 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 12IKXJAf053451 for ; Thu, 18 Mar 2021 20:33:19 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from bugzilla@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 12IKXJEg053450 for net@FreeBSD.org; Thu, 18 Mar 2021 20:33:19 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: bugzilla set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: net@FreeBSD.org Subject: [Bug 254366] Severe IPv6 TCP transfer issues on 13.0-RC2 with virtio network adapter Date: Thu, 18 Mar 2021 20:33:19 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 13.0-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: commit-hook@FreeBSD.org X-Bugzilla-Status: In Progress X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: tuexen@freebsd.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 18 Mar 2021 20:33:20 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D254366 --- Comment #18 from commit-hook@FreeBSD.org --- A commit in branch main references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=3Dd4697a6b56168876fc0ffec1a0bb1b24d= 25b198e commit d4697a6b56168876fc0ffec1a0bb1b24d25b198e Author: Michael Tuexen AuthorDate: 2021-03-18 20:25:47 +0000 Commit: Michael Tuexen CommitDate: 2021-03-18 20:32:20 +0000 vtnet: fix TSO for TCP/IPv6 The decision whether a TCP packet is sent over IPv4 or IPv6 was based on ethertype, which works correctly. In D27926 the criteria was changed to checking if the CSUM_IP_TSO flag is set in the csum-flags and then considering it to be TCP/IPv4. However, the TCP stack sets the flag to CSUM_TSO for IPv4 and IPv6, where CSUM_TSO is defined as CSUM_IP_TSO|CSUM_IP6_TSO. Therefore TCP/IPv6 packets gets mis-classified as TCP/IPv4, which breaks TSO for TCP/IPv6. This patch bases the check again on the ethertype. This fix will be MFC instantly as discussed with re(gjb). MFC after: instantly PR: 254366 Sponsored by: Netflix, Inc. Differential Revision: https://reviews.freebsd.org/D29331 sys/dev/virtio/network/if_vtnet.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --=20 You are receiving this mail because: You are on the CC list for the bug.=