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 77A5F1E48C; Thu, 21 Dec 2023 18:50:15 +0000 (UTC) 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 [192.168.1.104] (178.176.75.203) 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; Thu, 21 Dec 2023 21:50:07 +0300 From: Sergey Shtylyov Subject: Re: [PATCH net-next v2 20/21] net: ravb: Do not apply RX CSUM settings to hardware if the interface is down To: claudiu beznea , , , , , , , , , CC: , , , Claudiu Beznea References: <20231214114600.2451162-1-claudiu.beznea.uj@bp.renesas.com> <20231214114600.2451162-21-claudiu.beznea.uj@bp.renesas.com> <247ad9d9-298e-017b-f6e4-e672ee458ee7@omp.ru> <322c95f1-d42d-447d-89d1-7c61112b0cfd@tuxon.dev> Organization: Open Mobile Platform Message-ID: <101991df-0a00-b939-49db-d6fd425d0b50@omp.ru> Date: Thu, 21 Dec 2023 21:50:06 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <322c95f1-d42d-447d-89d1-7c61112b0cfd@tuxon.dev> Content-Type: text/plain; charset="utf-8" Content-Language: en-US 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: 12/21/2023 18:35:23 X-KSE-AntiSpam-Status: KAS_STATUS_NOT_DETECTED X-KSE-AntiSpam-Method: none X-KSE-AntiSpam-Rate: 59 X-KSE-AntiSpam-Info: Lua profiles 182285 [Dec 21 2023] X-KSE-AntiSpam-Info: Version: 6.1.0.3 X-KSE-AntiSpam-Info: Envelope from: s.shtylyov@omp.ru X-KSE-AntiSpam-Info: LuaCore: 7 0.3.7 6d6bf5bd8eea7373134f756a2fd73e9456bb7d1a X-KSE-AntiSpam-Info: {rep_avail} X-KSE-AntiSpam-Info: {Tracking_from_domain_doesnt_match_to} X-KSE-AntiSpam-Info: {relay has no DNS name} X-KSE-AntiSpam-Info: {SMTP from is not routable} X-KSE-AntiSpam-Info: {Found in DNSBL: 178.176.75.203 in (user) b.barracudacentral.org} X-KSE-AntiSpam-Info: {Found in DNSBL: 178.176.75.203 in (user) dbl.spamhaus.org} X-KSE-AntiSpam-Info: omp.ru:7.1.1;127.0.0.199:7.1.2;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1 X-KSE-AntiSpam-Info: ApMailHostAddress: 178.176.75.203 X-KSE-AntiSpam-Info: {DNS response errors} X-KSE-AntiSpam-Info: Rate: 59 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: 12/21/2023 18:38:00 X-KSE-Antivirus-Interceptor-Info: scan successful X-KSE-Antivirus-Info: Clean, bases: 12/21/2023 5:11:00 PM X-KSE-Attachment-Filter-Triggered-Rules: Clean X-KSE-Attachment-Filter-Triggered-Filters: Clean X-KSE-BulkMessagesFiltering-Scan-Result: InTheLimit On 12/17/23 5:34 PM, claudiu beznea wrote: [...] >>> From: Claudiu Beznea >>> >>> Do not apply the RX CSUM settings to hardware if the interface is down. In >>> case runtime PM is enabled, and while the interface is down, the IP will be >>> in reset mode (as for some platforms disabling/enabling the clocks will >>> switch the IP to standby mode, which will lead to losing registers' >> >> To/From perhaps? >> And just "register". >> >>> content) and applying settings in reset mode is not an option. Instead, >>> cache the RX CSUM settings and apply them in ravb_open(). >> >> Have this issue actually occurred for you? > > Setting RX CSUM while the if is down? No. > >>> Commit prepares for the addition of runtime PM. >>> >>> Signed-off-by: Claudiu Beznea >> [...] >> >>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c >>> index 633346b6cd7c..9ff943dff522 100644 >>> --- a/drivers/net/ethernet/renesas/ravb_main.c >>> +++ b/drivers/net/ethernet/renesas/ravb_main.c >>> @@ -1868,6 +1868,15 @@ static int ravb_open(struct net_device *ndev) >>> if (info->gptp || info->ccc_gac) >>> ravb_ptp_init(ndev, priv->pdev); >>> >>> + /* Apply features that might have been changed while the interface >>> + * was down. >>> + */ >>> + if (ndev->hw_features & NETIF_F_RXCSUM) { >> >> I'm afraid this is a wrong field; we need ndev->features, no? > > RX CSUM is not enabled for all ravb aware devices (see struct > ravb_hw_info::net_hw_features). We should be setting the ECMR only for > these ones. ravb_hw_info::net_hw_features is set in ndev->hw_features in > probe(). So here code checks if platforms supports RXCSUM and then below it > applies what has been requested though ndo_set_features(), if any. OK. But we don't need this snippet here anyway... >>> + u32 val = (ndev->features & NETIF_F_RXCSUM) ? ECMR_RCSC : 0; >>> + >>> + ravb_modify(ndev, ECMR, ECMR_RCSC, val); >>> + } >>> + >> >> The ECMR setting is already done in ravb_emac_init_rcar(), no need >> to duplicate it here, I think... > > Ok, it worth being moved there. No need to move, it's already there... [...] >>> @@ -2337,6 +2346,9 @@ static void ravb_set_rx_csum(struct net_device *ndev, bool enable) >>> struct ravb_private *priv = netdev_priv(ndev); >>> unsigned long flags; >>> >>> + if (!netif_running(ndev)) >> >> Racy as well... > > It's also called with rtnl_mutex locked. Well, at least the only place that calls the ndo_set_features() method, __netdev_update_features() calls ASSERT_RTNL() at the start. However, since we'd have to use the is_opened flag anyway, let's rely on it instead... [...] MBR, Sergey