From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx01.omp.ru (mx01.omp.ru [90.154.21.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2B3A94206E; Mon, 30 Sep 2024 19:30:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.154.21.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727724631; cv=none; b=DLpfaMaBkFxhbA6+/JtCngOPsfP99wQTdNdqAVJEOM+GEBrTmqdzldzt0B4g0WV/lUbN1L6Z13mXVqtW2X16r84s3gl5Z5TwYJfDutmKsXhHIuY7K5mXaghTiQUrhNRKYHtHAkXGQYW8Ct38h5Yggpzt8tJbWMMWCs39pUdr8nI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727724631; c=relaxed/simple; bh=OVm5n8rRgeWWLWcPZNj0/VWtcXnxpJfHbaBD144bNzk=; h=Message-ID:Date:MIME-Version:Subject:From:To:CC:References: In-Reply-To:Content-Type; b=LVdiEXFrbH/SM3xG6KGaJ9GBRDN3m2BqY3hTeK+MOXll4D0rX40V0V6daVLOFsK4ITaqvObaSiXOdNkQjvqPinLKf9ZUAOsbkTAXS2GwQlRyNZqUpc+14WqVAOioQLpLoGgy0FTCsgdw9nJjp912hUxRAsHEYI3V1MheuMwOnkw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=omp.ru; spf=pass smtp.mailfrom=omp.ru; arc=none smtp.client-ip=90.154.21.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=omp.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=omp.ru Received: from [192.168.2.100] (213.87.154.82) by msexch01.omp.ru (10.188.4.12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.1258.12; Mon, 30 Sep 2024 22:30:25 +0300 Message-ID: <8cb1de35-a40a-4d1b-a081-1b8fc08e0a6a@omp.ru> Date: Mon, 30 Sep 2024 22:30:25 +0300 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [net-next PATCH 05/11] net: ravb: Simplify types in RX csum validation From: Sergey Shtylyov To: Paul Barker , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni CC: Paul Barker , Geert Uytterhoeven , =?UTF-8?Q?Niklas_S=C3=B6derlund?= , Biju Das , Claudiu Beznea , , , References: <20240930160845.8520-1-paul@pbarker.dev> <20240930160845.8520-6-paul@pbarker.dev> Content-Language: en-US Organization: Open Mobile Platform In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: msexch01.omp.ru (10.188.4.12) To msexch01.omp.ru (10.188.4.12) X-KSE-ServerInfo: msexch01.omp.ru, 9 X-KSE-AntiSpam-Interceptor-Info: scan successful X-KSE-AntiSpam-Version: 6.1.0, Database issued on: 09/30/2024 19:14:44 X-KSE-AntiSpam-Status: KAS_STATUS_NOT_DETECTED X-KSE-AntiSpam-Method: none X-KSE-AntiSpam-Rate: 0 X-KSE-AntiSpam-Info: Lua profiles 188102 [Sep 30 2024] X-KSE-AntiSpam-Info: Version: 6.1.0.4 X-KSE-AntiSpam-Info: Envelope from: s.shtylyov@omp.ru X-KSE-AntiSpam-Info: LuaCore: 35 0.3.35 d90443ea3cdf6e421a9ef5a0a400f1251229ba23 X-KSE-AntiSpam-Info: {rep_avail} X-KSE-AntiSpam-Info: {Tracking_from_domain_doesnt_match_to} X-KSE-AntiSpam-Info: 127.0.0.199:7.1.2;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1;omp.ru:7.1.1 X-KSE-AntiSpam-Info: FromAlignment: s X-KSE-AntiSpam-Info: ApMailHostAddress: 213.87.154.82 X-KSE-AntiSpam-Info: Rate: 0 X-KSE-AntiSpam-Info: Status: not_detected X-KSE-AntiSpam-Info: Method: none X-KSE-AntiSpam-Info: Auth:dmarc=temperror header.from=omp.ru;spf=temperror smtp.mailfrom=omp.ru;dkim=none X-KSE-Antiphishing-Info: Clean X-KSE-Antiphishing-ScanningType: Heuristic X-KSE-Antiphishing-Method: None X-KSE-Antiphishing-Bases: 09/30/2024 19:18:00 X-KSE-Antivirus-Interceptor-Info: scan successful X-KSE-Antivirus-Info: Clean, bases: 9/30/2024 3:37:00 PM X-KSE-Attachment-Filter-Triggered-Rules: Clean X-KSE-Attachment-Filter-Triggered-Filters: Clean X-KSE-BulkMessagesFiltering-Scan-Result: InTheLimit On 9/30/24 22:11, Sergey Shtylyov wrote: [...] >> From: Paul Barker >> >> The HW checksum value is used as a 16-bit flag, it is zero when the > > I think I prefer s/HW/hardware/ but there's no hard feelings... :-) > >> checksum has been validated and non-zero otherwise. Therefore we don't >> need to treat this as an actual __wsum type or call csum_unfold(), we >> can just use a u16 pointer. >> >> Signed-off-by: Paul Barker > [...] >> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c >> index 1dd2152734b0..9350ca10ab22 100644 >> --- a/drivers/net/ethernet/renesas/ravb_main.c >> +++ b/drivers/net/ethernet/renesas/ravb_main.c > [...] >> @@ -762,23 +761,22 @@ static void ravb_rx_csum_gbeth(struct sk_buff *skb) [...] >> + if (unlikely(skb->len < csum_len)) >> return; >> >> if (skb_is_nonlinear(skb)) { >> - last_frag = &shinfo->frags[shinfo->nr_frags - 1]; >> - hw_csum = skb_frag_address(last_frag) + >> - skb_frag_size(last_frag); >> - skb_frag_size_sub(last_frag, 2 * sizeof(__sum16)); >> + skb_frag_t *last_frag = &shinfo->frags[shinfo->nr_frags - 1]; > > Could've been done in the previous patch... Even fit better there, I think... >> + >> + hw_csum = (u16 *)(skb_frag_address(last_frag) + >> + skb_frag_size(last_frag)); >> + skb_frag_size_sub(last_frag, csum_len); >> } else { >> - hw_csum = skb_tail_pointer(skb); >> - skb_trim(skb, skb->len - 2 * sizeof(__sum16)); >> + hw_csum = (u16 *)skb_tail_pointer(skb); >> + skb_trim(skb, skb->len - csum_len); >> } >> >> - hw_csum -= sizeof(__sum16); >> - csum_proto = csum_unfold((__force __sum16)get_unaligned_le16(hw_csum)); >> - >> - if (!csum_proto) >> + if (!*--hw_csum) > > Hm, you lost get_unaligned_le16() here. The checksum can be anywhere, > unaligned too... No need to keep using get_unaligned_le16() itself but you should then switch to using get_unaligned(). [...] MBR, Sergey