From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0FAA4C433F5 for ; Tue, 11 Jan 2022 17:11:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243460AbiAKRLJ (ORCPT ); Tue, 11 Jan 2022 12:11:09 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:43096 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244210AbiAKRLI (ORCPT ); Tue, 11 Jan 2022 12:11:08 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1641921067; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8zWK4tN+9sCHLKxamK/wjM5K43GyYWdN/7hQupmm6IE=; b=HGgJi0MxH4OEKaMBF1cgIem2z9hvj6DukcreX0Jbswj7cxJqw3x/rW3Ryc4HEQ8FjHETyB kuxRTGHgllOk07zi1cif/Y+pkS1rtMn1ccDASm163fnOTBlxU+EKwjtcYz/xjEHZfe0HwO ogYNhJ64gYVz+xJq+c9cU07KZnZn9qg= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-561-k-BwRD8XMLqt634tf77eTA-1; Tue, 11 Jan 2022 12:11:06 -0500 X-MC-Unique: k-BwRD8XMLqt634tf77eTA-1 Received: by mail-wr1-f71.google.com with SMTP id w25-20020adf8bd9000000b001a255212b7cso4961903wra.18 for ; Tue, 11 Jan 2022 09:11:06 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:user-agent:mime-version:content-transfer-encoding; bh=8zWK4tN+9sCHLKxamK/wjM5K43GyYWdN/7hQupmm6IE=; b=o5O2B8+JdUrkwuDggGHuUJFAAWvDkLDEVfMDhKuP3+zFSqJHzFIukUCg6YJZELpccd OR0VaXg7y7Tr3OqzQL4fhJRfMv4RrMRajC8J+82eTKSQM4DxtVv6xJhrxC+Bfh0F4CCu k4VGCoI8ob36D6Nkzvp5GQDkhQ1LRZRN3ytmDIvxuLv+rcOszDV+m5IVGzoLK3xphMwB VcaBcd+Y9cLQfJjjwpkyvN2c5sxTYVQWZ5cF/UZXFLDcTMhavr5cle7Its+meEqb8fzB yZ5CoEkS9lwRNCpSx6SPeNIGbr+JCcdDEq9ETqjz69wY59iz4ZY6pObgYbYQfPG0yY5j pTBA== X-Gm-Message-State: AOAM530BD2drixm2on65ykGYsL4T4xcNp5Wh3QHEysAU4wIpnJPSG3Nv VJA+cPEBPSJXQ9l9uenkTfTOT6oJAq6qh+KGtSF63D5FcAoTPYX2n+VWQDTL8wkHYn+/S7kWywm 3NIywGRXu16p3bCsk X-Received: by 2002:adf:d222:: with SMTP id k2mr4451520wrh.332.1641921065237; Tue, 11 Jan 2022 09:11:05 -0800 (PST) X-Google-Smtp-Source: ABdhPJyXpslAh5ADGc3957eLtWJpzW3P/MighujLUPuX4ruiB8rgSb0yOAB/BZQ8T7j19gWqojV1vQ== X-Received: by 2002:adf:d222:: with SMTP id k2mr4451503wrh.332.1641921065031; Tue, 11 Jan 2022 09:11:05 -0800 (PST) Received: from gerbillo.redhat.com (146-241-96-254.dyn.eolo.it. [146.241.96.254]) by smtp.gmail.com with ESMTPSA id z4sm2116440wmf.44.2022.01.11.09.11.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 11 Jan 2022 09:11:04 -0800 (PST) Message-ID: <48293134f179d643e9ec7bcbd7bca895df7611ac.camel@redhat.com> Subject: Re: [PATCH 09/14] ipv6: hand dst refs to cork setup From: Paolo Abeni To: Pavel Begunkov , netdev@vger.kernel.org, "David S . Miller" , Jakub Kicinski Cc: Hideaki YOSHIFUJI , David Ahern , Eric Dumazet , Willem de Bruijn , linux-kernel@vger.kernel.org Date: Tue, 11 Jan 2022 18:11:03 +0100 In-Reply-To: <07031c43d3e5c005fbfc76b60a58e30c66d7c620.1641863490.git.asml.silence@gmail.com> References: <07031c43d3e5c005fbfc76b60a58e30c66d7c620.1641863490.git.asml.silence@gmail.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.42.2 (3.42.2-1.fc35) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, 2022-01-11 at 01:21 +0000, Pavel Begunkov wrote: > During cork->dst setup, ip6_make_skb() gets an additional reference to > a passed in dst. However, udpv6_sendmsg() doesn't need dst after calling > ip6_make_skb(), and so we can save two additional atomics by passing > dst references to ip6_make_skb(). udpv6_sendmsg() is the only caller, so > it's enough to make sure it doesn't use dst afterwards. What about the corked path in udp6_sendmsg()? I mean: udp6_sendmsg(MSG_MORE) -> ip6_append_data() -> ip6_setup_cork() what if ip6_setup_cork() errors out in that path? Thanks! Paolo