From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=209.85.128.52 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794500816; b=3plKT+5K2fZQYdKspTCxw9ayPWKWar5OT3k69SCEYiqdj+4YJG4u4b51ReTtniUBgPi2 fShGQbvaZxjBFFppZJQrs3VoYxADjPhZda/FmoKnc8DwZEAXCBDGIJSagFwNezLP6H37n /8tqKqQg8ul6ilHx2AsE+kzWbrULVeDBm7++YDK8XyD64/UxbrCqL4XTL6i3c657uishT 8E9CHdapoMGSQknhrrQMsc/bj6Y44gkBZVsdujPgXDMxVupJW3y3OsWvfBg2LfNekIvs8 FsPfBzvQ/F4xHUfwaKLXRV90UkEHHAqmicGCtItb6r8ilajheXaMg1tAhI6odaNVm3w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794500816; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Gm-Message-State:X-Gm-Gg:X-Received:Received:Message-ID:Date: MIME-Version:User-Agent:Reply-To:Subject:To:Cc:References:From: Content-Language:Organization:In-Reply-To:Content-Type: Content-Transfer-Encoding; bh=QQ/3quzm4feLEDq5prptw7Btjz+8je4ZUZGF6TJco1M=; b=sKJgDPF5u3usLtXesru7DOnHwXOk1n3w9n2Dy7dd2JS1u84mg1thqHVKtI95BEPAjc+a PKh23GCZSQDWjPD7tEgbFNC17A8EM//AqX80JyjCrkI9BPeLd1rnLQJi2EqQDp8bCj14S KMqtU+8O+iWiqEDKInZ1fEJaOffhvMApkF1nI5pvtilhY+NC2QLHQs1J0x3affqB5wl5G w22wSZfKO5ZcifgpAjONiKp8j4TB6IDhaEEB6awEdMuvjDscHOkxjlPEfb0qF4aW/f13B Oy9zp0q07g/Tu5qOxndGJEqVQ/cFEhp4mbGrAb0+TEpCWjEC0zJsnavXbshkQwdKOgg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=6wind.com; spf=pass smtp.mailfrom=6wind.com; dkim=pass header.d=6wind.com header.i=@6wind.com header.a=rsa-sha256 header.s=google header.b="EtFg/kC9"; arc=none smtp.remote-ip=209.85.128.52 Received: from mail-wm1-f52.google.com (mail-wm1-f52.google.com [209.85.128.52]) (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 D1072606A888 for ; Thu, 12 Nov 2026 16:26:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org D1072606A888 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=6wind.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=6wind.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=6wind.com header.i=@6wind.com header.a=rsa-sha256 header.s=google header.b=EtFg/kC9 Received: by mail-wm1-f52.google.com with SMTP id 5b1f17b1804b1-4a56e05568aso4725875e9.1 for ; Thu, 12 Nov 2026 08:26:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=6wind.com; s=google; t=1794500814; x=1795105614; darn=vger.kernel.org; h=content-transfer-encoding:content-type:in-reply-to:organization :content-language:from:references:cc:to:subject:reply-to:user-agent :mime-version:date:message-id:from:to:cc:subject:date:message-id :reply-to:content-type; bh=QQ/3quzm4feLEDq5prptw7Btjz+8je4ZUZGF6TJco1M=; b=EtFg/kC9y1DirVvA9yLbTRagqhSjkLk6ziYDwHAP1xD7Xmb6LsmwWC8mOetg+tDeZh xWqqP6oEWPZigH9h1x3dDWabH29oHWXXy8GyR9+grcWK9NGsuRdMLxx+2jW5MXAnBZ+b H/lsp0vaUjFdhS/GF2SD93gAx8GKeho3HqXqonlGauq2eoZZ/MrWpHCfCZ3KE4KEYOUt fqiTFrUhHUh8TyyYD+ozgnb4Vl8qqidvow3BWLG4cR49WWZCTr/lQPU+eMqBNf3k50R3 sT9Nx29c5j6NPlP/T/8cZnAXmYTOw+p/EfAeODvgcT6FR3gbNvbFp0tzEYIJwXmERdqj v7Qg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1794500814; x=1795105614; h=content-transfer-encoding:content-type:in-reply-to:organization :content-language:from:references:cc:to:subject:reply-to:user-agent :mime-version:date:message-id:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to:content-type; bh=QQ/3quzm4feLEDq5prptw7Btjz+8je4ZUZGF6TJco1M=; b=DTXosG67CZryEc1YJm2X2Wb56futIOY6nw+D39Fk2486sO4TBRj8ENQ1ibYkuH1Qx/ Ev8vC53qzMgG2+HwbHRpzBb6x/TBh3iq1ULlJzHqhzSeHpRP1ira86JIg9zmbaH22Xxz 03EQmJ4+lIfOMeOs8JVvVFMDNI9WKOyHjosJGRDIEzD3ZojNrPnp38m6i9dUubXm90Ya 4F39rHgkuROmptCa2d9c94QMTiau4na885ZKVG6XYyRk38+JlG/OoKswFj6oT+WpKOhT WOTucl7NS03uGbCvPCGiyA6rDc00O5t32/JF6FKIqQz3VGB0KDoak4q7kCGWeNNEzymB QAdw== X-Gm-Message-State: APuU4Z+tNEgjz+eAv9oC2tmRH+iSX5kF3oZpzMYW0/I4JdSZ6O9jNOPi JPHlh1hE4jUCghrpcTBPm4p95xroN8eNPjTCVuQpU16cIIHZXCiEU9rnF82ZJpNEIEQ= X-Gm-Gg: AYBFou0rN7sR612nIzSABG/u6XK8t2zTVc/kg9oZduACBWNj3tQy+wg3EJInnmCKsox NMA1UKNZw9z+JVLixzMNznzMQDdAW8YPhAUDIR2Iyo93KDY2LQ92W9K3UZ4VHwwPlt+eIcfovYy AFARJkNtu0emt/XXXcRW+7MpATOBJfV5Cgd2kfKa0w0/qzexY2GLGd3pSctzOTNKOryoostWq2d WsoC9Rr1PsAyMDFLuThjhbv5hcZT/LOx7qIl7v829YCAT94/zZ2As63fqiVCfbSwalU9c745cTO 85ORZhNdy32X8Rv4A3BSw+oJNGyp2SeiZF7KKO+0f1FAEHWXCQclTF7SkL1L+v3UCG/DSyo2t1s fwk7qyxjLG78CmZq0ZjdMRag1Wo6ZWnn8mS86sHy2Y0xEW/m3obHttH/DpwoLz80uR4CuROd+Gi OVGi0Z15wbp0/NTvdTiDDfM4xlQHkVlvQlZwfVFUPy52S0Oh2urS5J9FYrUfgUvIQWZmN2avUkI 3WWT4j48/2O6ZOS4Hwzh3hclofQ/yYpVBO3oLNTEgKWKXBmFhVwct6k2MsATFbM5ow8nYIaAGwn ESqVLsZ66xzF0QqF4ejPAYB1PNIWoiE+JnPoKTvg5+Bq6FDGdmNBb1fs2I6+6oscq6SPB1N6nNT XwV02jg== X-Received: by 2002:a05:6000:1788:b0:490:540:f95f with SMTP id ffacd0b85a97d-499c92284d1mr12368002f8f.5.1794500814316; Thu, 12 Nov 2026 08:26:54 -0800 (PST) Received: from ?IPV6:2a01:e0a:ab7:2110:6a1d:efff:fe52:1959? ([2a01:e0a:ab7:2110:6a1d:efff:fe52:1959]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-49c607d12c4sm84484f8f.41.2026.11.12.08.26.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 12 Nov 2026 08:26:53 -0800 (PST) Message-ID: Date: Thu, 12 Nov 2026 17:26:53 +0100 X-Mailing-List: netdev@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Reply-To: nicolas.dichtel@6wind.com Subject: Re: [PATCH net-next] ipv6: always apply all.force_forwarding to every interface To: Gabriel Goller , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Jonathan Corbet , Shuah Khan , Randy Dunlap , David Ahern , Ido Schimmel Cc: netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org References: <20261112-ipv6_always_apply-v1-1-8df846631005@proxmox.com> From: Nicolas Dichtel Content-Language: en-US Organization: 6WIND In-Reply-To: <20261112-ipv6_always_apply-v1-1-8df846631005@proxmox.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Le 12/11/2026 à 14:41, Gabriel Goller a écrit : > Currently, writing to all.force_forwarding updates the interfaces > only if the value stored in all.force_forwarding changes. Setting an > interface to a different value and then writing the same value to all > leaves that interface unchanged: > > # sysctl -wq net.ipv6.conf.all.force_forwarding=1 > # sysctl -wq net.ipv6.conf.dummy1.force_forwarding=0 > # sysctl -wq net.ipv6.conf.all.force_forwarding=1 > # sysctl net.ipv6.conf.dummy1.force_forwarding > net.ipv6.conf.dummy1.force_forwarding = 0 > > Apply every write to all.force_forwarding to all interfaces, even when > its stored value is unchanged, matching all.forwarding. In the example, > the final write to all now sets dummy1.force_forwarding back to 1. > > Also match forwarding's locking: take RTNL for every write and compare > the old and new values under the lock, rather than returning early based > on an unlocked comparison. Send netconf notifications only for actual > value changes, including for default and per-interface writes. > > Note that IPv4's forwarding does not behave like this, but we won't > change that one and align force_forward to the IPv6 forwarding. > > Fixes: f24987ef6959 ("ipv6: add `force_forwarding` sysctl to enable per-interface forwarding") > Suggested-by: Nicolas Dichtel > Signed-off-by: Gabriel Goller Reviewed-by: Nicolas Dichtel