From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=95.215.58.166 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792602239; b=P88HeanM0eRa/vthmd5p7V/RKgXk+ITQtwQj4Z3IISJycSwo/cNrmBrleNyPCAxDWtkp kb5SjW58EHGVXztUhyfgaJr43fdN8NKeRg2J1UeLixKzbLnobMqaFHfaDWe4PRE13tb25 XFM1MFvjzT8itVs7UsAeLkxWSUMgzORt785KcBhimNCYxQGPxxf2q9lZhtshmfFFNVeMU jqwdvOgeKvE0tKi3hOaL3E0D1UywyKR0GQwOktke/KAsHpx4YVweLKxYmgqDHGZg3ih8d AoQOdEk3xHHp+dpScL/6kmEjq7chfESOXBQ3SPOWHL3s4DVTZj1nZw2fm/bLuWYokqg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792602239; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:Message-ID:Date:MIME-Version:User-Agent: Subject:To:Cc:References:Content-Language:From:In-Reply-To: Content-Type:Content-Transfer-Encoding; bh=XxkAtzk3cuV4R/7ZEJ4B77roig8TiSn44g1A3T9utgI=; b=B6dVj+b0AZrrbB2PSTKpASJKt2XwmuwgHeYD5GXB+bhO6juw+EQiTJL3mUEQDl1yRzOR FqjuDqa0jmoRfurv3vNy7lfkfw36X3+ZPQsbeKPBxn4+TpUpv8hkVlz1L8XDjoUa6diSm CJPHlhYhBWMAmFo7QbPBfTPp4r91YDHbftkRdCuG+f1QpuRsyWyhrXDmWDYgCdDWeNl7i 2tef7EbtUB0s8uD4knvy5AOhxvBvnqJ5sjYg+nEPE25xgyn5VJk+wDxcwN4Xivjfc/Cgh Zg/hntddZZUlOLs97mxrfoFfG8weMNTaJkEP2sJ/pFyFUmFEnkLqsa6aAioTvwAducA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=OKzhBjGE; arc=none smtp.remote-ip=95.215.58.166 Received: from mta1.migadu.com (out-166.mta1.migadu.com [95.215.58.166]) (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 B8F55606A31B for ; Wed, 21 Oct 2026 17:03:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org B8F55606A31B Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=OKzhBjGE X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=xxzknvAGwBqrx+ryt5T3qM3aIvNfAZ9P3IcDt4rnT4w=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1792602236; v=1; x=1793207036; b=OKzhBjGEncpgo3Uz3/LILxAqU/+xcGGiC7mavksAJYiq3PMGFkBOisxga95iE3oHTTuyKuhB M6cpiiUbcmVjfp75wVT6QnKK+Ui/yyjMS1BAZAZsCmOKVzrhmHTOh4+AZbDa6bzIAftpDE2xSeR qiZVGnmdkMLCYqQCxM8nt4/s= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id d445459a510384bd; Wed, 21 Oct 2026 17:03:56 +0000 X-Mizu-Trace-ID: d445459a510384bd X-Migadu-Flow: FLOW_OUT Message-ID: <51ccddcc-53b0-47cd-9526-ccd825f0f6d9@linux.dev> Date: Thu, 22 Oct 2026 01:03:48 +0800 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 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net] ppp: linearize bridged packets when required To: Eric Dumazet Cc: netdev-bot+sinfo@kernel.org, Andrew Lunn , "David S. Miller" , Jakub Kicinski , Paolo Abeni , Breno Leitao , Kees Cook , Taegu Ha , Tom Parkin , linux-ppp@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, James Chapman , Sashiko , Felix Fietkau , Pablo Neira Ayuso References: <20261021023608.55867-1-qingfang.deng@linux.dev> <179255036282.3290.8488375760281728576@kernel.org> <315a8794-db40-4d0f-9e4c-0cad66174bff@linux.dev> Content-Language: en-US From: Qingfang Deng In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 10/22/2026 12:31 AM, Eric Dumazet wrote: > Le mer. 21 oct. 2026 à 12:27, Qingfang Deng a écrit : >>> + case PPP_IP: >>> + skb->protocol = htons(ETH_P_IP); >>> + break; >>> + case PPP_IPV6: >>> + skb->protocol = htons(ETH_P_IPV6); >>> + break; >>> + default: >>> + goto drop; >>> + } >>> + skb_set_network_header(skb, PPP_PROTO_LEN); >>> + >>> + segs = skb_gso_segment(skb, 0); >> >> Passing zero features to skb_gso_segment will linearize every segment >> prematurely. > > Good point, PPTP and L2TP do not need linear packets. > I will pass NETIF_F_SG: checksums are still computed in software by > skb_segment(), as openvswitch does, and ppp_bridge_xmit() linearizes > segments only for channels without direct_xmit. What about NETIF_F_FRAGLIST?