From patchwork Wed Jan 25 07:48:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Magnus Karlsson X-Patchwork-Id: 13115052 X-Patchwork-Delegate: kuba@kernel.org 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 65ED6C61D97 for ; Wed, 25 Jan 2023 07:49:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234832AbjAYHtT (ORCPT ); Wed, 25 Jan 2023 02:49:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44496 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233434AbjAYHtQ (ORCPT ); Wed, 25 Jan 2023 02:49:16 -0500 Received: from mail-wm1-x332.google.com (mail-wm1-x332.google.com [IPv6:2a00:1450:4864:20::332]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CE5F640BD0; Tue, 24 Jan 2023 23:49:14 -0800 (PST) Received: by mail-wm1-x332.google.com with SMTP id f12-20020a7bc8cc000000b003daf6b2f9b9so617406wml.3; Tue, 24 Jan 2023 23:49:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=s88uykPtdjaIE1LL1cMvTHnMWGpsOLKtW5AjDErmIYQ=; b=GXg9vUa/G4833/HQe9V59OIdzus4jtq+lK34Z48jEO++Os4bEdOQ5Cp0f13LYu2ywp 4bgehdWfppA8TK7p02MAf71bAHJG2gJZpsGPLI3PNkHMKbOokRdiUQW+yuHMyPGdotd4 zzi3PKnv6SeVQg1oS5IYB+YSNqKpkt62y1wvDGkCfU8BfYdImmCs5T8eKNTky9BgxLad 46a+kO1IUUroOgNLAchbfE8dZYa1RiKQKqwOfndZsYwgUSi7hYhgJ7FClcK8nuktgrWs XEkH2O6ORPzUyQ5TcgSyXmTQ90HF8h3A1dl23UZ9U3fAt2n5M7wtJ6S0Krn/idNPYmQm NeOA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=s88uykPtdjaIE1LL1cMvTHnMWGpsOLKtW5AjDErmIYQ=; b=OdmrYIm5vz4HhlcvA/V5As6BKF2vUHi6BA8zA4STM27uLBRdW8yD1T+H5l8HXPxyB/ k/dDZiG5xeJGti8+8mTgL4uT9SfU5sBhzcDyQ5/cO+xnOqD5EMm4FyFFMBfQYv5G8EAq WrztMUermIOV15TfVAt/QjviP+/dz2lSepZLh5171Le/YUHAXvtA3YGexM8rdsuD1i7+ lCnF0DhRRes2HPxTT0FpCtZqmnHjz+Hc+eI/gwcVuixZHLe85HrWnmDgbiWSRRAQBprz T7bL/rQI5hyU73k6CoLqtc4qfukbLL7c6G3NRy/NHBFeoiG413hONv8S+I2pPvzK9ZMW 6uEw== X-Gm-Message-State: AFqh2kqdJaEcOHICxBRRKrt2HvrwHUYRRXpy/wD/2/u95BJ5F001KMBn u6Z1x1WmHI6bEWhPE3ynykoK2HtGknpWx9aG X-Google-Smtp-Source: AMrXdXspaFhwq5oY32woUbOssYGHz5I4Lqg+KdU6YYYogLaMmZLfWv1Vbtl4OhqAePl45SgWL9uTTg== X-Received: by 2002:a05:600c:304a:b0:3d9:8635:a916 with SMTP id n10-20020a05600c304a00b003d98635a916mr32126347wmh.9.1674632953196; Tue, 24 Jan 2023 23:49:13 -0800 (PST) Received: from localhost.localdomain (h-176-10-254-193.A165.priv.bahnhof.se. [176.10.254.193]) by smtp.gmail.com with ESMTPSA id n13-20020a05600c500d00b003db2b81660esm1032051wmr.21.2023.01.24.23.49.11 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 24 Jan 2023 23:49:12 -0800 (PST) From: Magnus Karlsson To: magnus.karlsson@intel.com, bjorn@kernel.org, ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, jonathan.lemon@gmail.com, maciej.fijalkowski@intel.com, kuba@kernel.org, toke@redhat.com, pabeni@redhat.com, davem@davemloft.net, aelior@marvell.com, manishc@marvell.com, horatiu.vultur@microchip.com, UNGLinuxDriver@microchip.com, mst@redhat.com, jasowang@redhat.com, ioana.ciornei@nxp.com, madalin.bucur@nxp.com Cc: bpf@vger.kernel.org Subject: [PATCH net v2 1/5] qede: execute xdp_do_flush() before napi_complete_done() Date: Wed, 25 Jan 2023 08:48:57 +0100 Message-Id: <20230125074901.2737-2-magnus.karlsson@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230125074901.2737-1-magnus.karlsson@gmail.com> References: <20230125074901.2737-1-magnus.karlsson@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Magnus Karlsson Make sure that xdp_do_flush() is always executed before napi_complete_done(). This is important for two reasons. First, a redirect to an XSKMAP assumes that a call to xdp_do_redirect() from napi context X on CPU Y will be followed by a xdp_do_flush() from the same napi context and CPU. This is not guaranteed if the napi_complete_done() is executed before xdp_do_flush(), as it tells the napi logic that it is fine to schedule napi context X on another CPU. Details from a production system triggering this bug using the veth driver can be found following the first link below. The second reason is that the XDP_REDIRECT logic in itself relies on being inside a single NAPI instance through to the xdp_do_flush() call for RCU protection of all in-kernel data structures. Details can be found in the second link below. Fixes: d1b25b79e162b ("qede: add .ndo_xdp_xmit() and XDP_REDIRECT support") Signed-off-by: Magnus Karlsson Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/r/20221220185903.1105011-1-sbohrer@cloudflare.com Link: https://lore.kernel.org/all/20210624160609.292325-1-toke@redhat.com/ --- drivers/net/ethernet/qlogic/qede/qede_fp.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/qlogic/qede/qede_fp.c b/drivers/net/ethernet/qlogic/qede/qede_fp.c index 7c2af482192d..cb1746bc0e0c 100644 --- a/drivers/net/ethernet/qlogic/qede/qede_fp.c +++ b/drivers/net/ethernet/qlogic/qede/qede_fp.c @@ -1438,6 +1438,10 @@ int qede_poll(struct napi_struct *napi, int budget) rx_work_done = (likely(fp->type & QEDE_FASTPATH_RX) && qede_has_rx_work(fp->rxq)) ? qede_rx_int(fp, budget) : 0; + + if (fp->xdp_xmit & QEDE_XDP_REDIRECT) + xdp_do_flush(); + /* Handle case where we are called by netpoll with a budget of 0 */ if (rx_work_done < budget || !budget) { if (!qede_poll_is_more_work(fp)) { @@ -1457,9 +1461,6 @@ int qede_poll(struct napi_struct *napi, int budget) qede_update_tx_producer(fp->xdp_tx); } - if (fp->xdp_xmit & QEDE_XDP_REDIRECT) - xdp_do_flush_map(); - return rx_work_done; } From patchwork Wed Jan 25 07:48:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Magnus Karlsson X-Patchwork-Id: 13115053 X-Patchwork-Delegate: kuba@kernel.org 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 79755C61DA2 for ; Wed, 25 Jan 2023 07:49:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234860AbjAYHtT (ORCPT ); Wed, 25 Jan 2023 02:49:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44562 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234420AbjAYHtR (ORCPT ); Wed, 25 Jan 2023 02:49:17 -0500 Received: from mail-wm1-x32e.google.com (mail-wm1-x32e.google.com [IPv6:2a00:1450:4864:20::32e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DD1574943B; Tue, 24 Jan 2023 23:49:16 -0800 (PST) Received: by mail-wm1-x32e.google.com with SMTP id g10so13088162wmo.1; Tue, 24 Jan 2023 23:49:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=6aa1jo3Gm6IQD13Q3su+lnnZXPzXg/tUFIWCE6r8QJU=; b=iSgK2/Pi9HJwCbrRBVMur6oVbbvyIHBYBsY+Itbzsm+nk2ohtDmfjbzkTQyPszr4v/ QKHifA7gFr91fFiE0ypCeRngWzYhZzSptXo1Z8RXA27vsr2jcR7yaC96UKnO7NL7ZxfK 68amlVNJAomthjAq+aB/CQAe14ga/9qNTqm59HQeKO1r+TM2z5zgPlTSNgmxkfdRql6/ VM/HhXO5IEPXr0u3/a4Xnk9GuUMOAXqq5AjUf9ck3LtpxYi5s2Lw4hAjmwZi13xUcmY0 db1yP0be3RoeomcU92fzXkhef5N6yOkMnmAEJ5mvDgexoBKrmWfR6tGtETrRII6NWW+N 4uHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=6aa1jo3Gm6IQD13Q3su+lnnZXPzXg/tUFIWCE6r8QJU=; b=dl97JX3456NbZychXH+yregooxNpE46P5bbi/BeT3rUbK8qIgCIbZ3JCBCXXOG52lM oJ92hP5jht8sxmyMsMxdMP2hz35PvUJEATwniAtHEdNZyHKI+yhw8IY/Jgmz0lvTqUOj XxvPvM/4znBEa+4VxOoPlNK4UGzlWxH5c9MnWxPil6UMzbNe9ymaWnhJJMzyG4IvCmD5 x+5wBWEaXq9vGus6crek6b3Fit/+En1lnbfeWeBxlheELyI1W4Al3Owxj4GDN6KVruks kTAiZYvCk2TgKi0W+wsE/0PpAt7YLNw4LCACfm6N70sd6Wtc0Qlavdhe0179wkh8VN5Q ByHQ== X-Gm-Message-State: AFqh2kp/Vz9NMHaAqEWRoLyu5MLWGuA8jK/tcp7rUlyP/Kme3xtVuocU MrFMojSPvBC9HhdWXcUvofY= X-Google-Smtp-Source: AMrXdXt+oFJn5hWkI9BLdUFy9INfrqJo3BZQbOAvYIZSrp9vV9fGYOWE9iv9hwshiA3FYcnew163vQ== X-Received: by 2002:a05:600c:920:b0:3da:22a6:7b6b with SMTP id m32-20020a05600c092000b003da22a67b6bmr30971526wmp.13.1674632955251; Tue, 24 Jan 2023 23:49:15 -0800 (PST) Received: from localhost.localdomain (h-176-10-254-193.A165.priv.bahnhof.se. [176.10.254.193]) by smtp.gmail.com with ESMTPSA id n13-20020a05600c500d00b003db2b81660esm1032051wmr.21.2023.01.24.23.49.13 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 24 Jan 2023 23:49:14 -0800 (PST) From: Magnus Karlsson To: magnus.karlsson@intel.com, bjorn@kernel.org, ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, jonathan.lemon@gmail.com, maciej.fijalkowski@intel.com, kuba@kernel.org, toke@redhat.com, pabeni@redhat.com, davem@davemloft.net, aelior@marvell.com, manishc@marvell.com, horatiu.vultur@microchip.com, UNGLinuxDriver@microchip.com, mst@redhat.com, jasowang@redhat.com, ioana.ciornei@nxp.com, madalin.bucur@nxp.com Cc: bpf@vger.kernel.org, Steen Hegelund Subject: [PATCH net v2 2/5] lan966x: execute xdp_do_flush() before napi_complete_done() Date: Wed, 25 Jan 2023 08:48:58 +0100 Message-Id: <20230125074901.2737-3-magnus.karlsson@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230125074901.2737-1-magnus.karlsson@gmail.com> References: <20230125074901.2737-1-magnus.karlsson@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Magnus Karlsson Make sure that xdp_do_flush() is always executed before napi_complete_done(). This is important for two reasons. First, a redirect to an XSKMAP assumes that a call to xdp_do_redirect() from napi context X on CPU Y will be followed by a xdp_do_flush() from the same napi context and CPU. This is not guaranteed if the napi_complete_done() is executed before xdp_do_flush(), as it tells the napi logic that it is fine to schedule napi context X on another CPU. Details from a production system triggering this bug using the veth driver can be found following the first link below. The second reason is that the XDP_REDIRECT logic in itself relies on being inside a single NAPI instance through to the xdp_do_flush() call for RCU protection of all in-kernel data structures. Details can be found in the second link below. Fixes: a825b611c7c1 ("net: lan966x: Add support for XDP_REDIRECT") Signed-off-by: Magnus Karlsson Acked-by: Toke Høiland-Jørgensen Acked-by: Steen Hegelund Link: https://lore.kernel.org/r/20221220185903.1105011-1-sbohrer@cloudflare.com Link: https://lore.kernel.org/all/20210624160609.292325-1-toke@redhat.com/ --- drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c index 5314c064ceae..55b484b10562 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c @@ -608,12 +608,12 @@ static int lan966x_fdma_napi_poll(struct napi_struct *napi, int weight) lan966x_fdma_rx_reload(rx); } - if (counter < weight && napi_complete_done(napi, counter)) - lan_wr(0xff, lan966x, FDMA_INTR_DB_ENA); - if (redirect) xdp_do_flush(); + if (counter < weight && napi_complete_done(napi, counter)) + lan_wr(0xff, lan966x, FDMA_INTR_DB_ENA); + return counter; } From patchwork Wed Jan 25 07:48:59 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Magnus Karlsson X-Patchwork-Id: 13115054 X-Patchwork-Delegate: kuba@kernel.org 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 A940CC27C76 for ; Wed, 25 Jan 2023 07:49:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234885AbjAYHtV (ORCPT ); Wed, 25 Jan 2023 02:49:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234833AbjAYHtT (ORCPT ); Wed, 25 Jan 2023 02:49:19 -0500 Received: from mail-wm1-x332.google.com (mail-wm1-x332.google.com [IPv6:2a00:1450:4864:20::332]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C302A49950; Tue, 24 Jan 2023 23:49:17 -0800 (PST) Received: by mail-wm1-x332.google.com with SMTP id f12-20020a7bc8cc000000b003daf6b2f9b9so617487wml.3; Tue, 24 Jan 2023 23:49:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=xmo4viDahGQArnmS4tCJdyEC7O2nKFQBmZiFDh4E4Aw=; b=bpwJVTZmhC3HFJ2BAi2Z7lUWA9H+1qcxkF4OysKlNTJVEJJIJwGI6yQHPh+9A41Faa HiggUDZ+A6QWCHWgjAcD3zKrlnjzE+RPMo7mcWWiiI/ToZfWKetQEDl0qRv/4Usb4rM4 6HMlJazbq97JSnkHYlLUb9pUELEFTPSiXUEFBJO4YQ4DNt69+/6jfos4qmyvqApMyn9q YR4BZTICwHKhK9AE0dl3hro37jLr1U6e0dCpww46HKagsAvXjnnG4FeKwlzQ1oVI+ewh T4fYT8ssk7Hwzedx8HggtxSyiIsNhc0P9GDNyfdirJhgf57JGG3o8ZJaLnYhOP76W5L9 Ckfw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=xmo4viDahGQArnmS4tCJdyEC7O2nKFQBmZiFDh4E4Aw=; b=sXK9KN9wNn3zKFXwkZAeo/tGuco5ZUi09SyiMMTxsUPj4GbImPsPRdeobXCzwmc0QN MT4xeaPNN6LqxcyfcI99k/f06vRSolAbj3aLSPoWgk9UMg9DpMk38kzZlTRT25ow/EYq ka1fuYqUgcjwEsaV1B1pycGUhK1hR+LxblCJMI+iCjzmB6hcAU+qvcFFFZv3hEjarQkW 6k1n8zIwESWdqKisUGyooiIqjC2rjSt5u9vKrNRtx8RLaNQoqTwLl7xH4Zuz6GJB3NtZ +HxLxrGTfThaMZHal6nELufluWD4NHT58MvnbxDbbXNhez+WFr9hjdX0xVQKsWtDaem/ R1iw== X-Gm-Message-State: AFqh2kqPlTi5OSVlIVXaQmitOBXRwaFsmjRNuwG++dnpLj0vIHEMApJM gb9esUN5feGyEy0SEkNlUY8= X-Google-Smtp-Source: AMrXdXuRiTTUXHzVJtIqPkU7yfp0FE6szlOO2ITdCnfKFBmI36bpubMiX1sgEnrrVyrpf6MRpG6T0w== X-Received: by 2002:a05:600c:4928:b0:3d9:a5a2:65fa with SMTP id f40-20020a05600c492800b003d9a5a265famr30523857wmp.7.1674632957288; Tue, 24 Jan 2023 23:49:17 -0800 (PST) Received: from localhost.localdomain (h-176-10-254-193.A165.priv.bahnhof.se. [176.10.254.193]) by smtp.gmail.com with ESMTPSA id n13-20020a05600c500d00b003db2b81660esm1032051wmr.21.2023.01.24.23.49.15 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 24 Jan 2023 23:49:16 -0800 (PST) From: Magnus Karlsson To: magnus.karlsson@intel.com, bjorn@kernel.org, ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, jonathan.lemon@gmail.com, maciej.fijalkowski@intel.com, kuba@kernel.org, toke@redhat.com, pabeni@redhat.com, davem@davemloft.net, aelior@marvell.com, manishc@marvell.com, horatiu.vultur@microchip.com, UNGLinuxDriver@microchip.com, mst@redhat.com, jasowang@redhat.com, ioana.ciornei@nxp.com, madalin.bucur@nxp.com Cc: bpf@vger.kernel.org Subject: [PATCH net v2 3/5] virtio-net: execute xdp_do_flush() before napi_complete_done() Date: Wed, 25 Jan 2023 08:48:59 +0100 Message-Id: <20230125074901.2737-4-magnus.karlsson@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230125074901.2737-1-magnus.karlsson@gmail.com> References: <20230125074901.2737-1-magnus.karlsson@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Magnus Karlsson Make sure that xdp_do_flush() is always executed before napi_complete_done(). This is important for two reasons. First, a redirect to an XSKMAP assumes that a call to xdp_do_redirect() from napi context X on CPU Y will be followed by a xdp_do_flush() from the same napi context and CPU. This is not guaranteed if the napi_complete_done() is executed before xdp_do_flush(), as it tells the napi logic that it is fine to schedule napi context X on another CPU. Details from a production system triggering this bug using the veth driver can be found following the first link below. The second reason is that the XDP_REDIRECT logic in itself relies on being inside a single NAPI instance through to the xdp_do_flush() call for RCU protection of all in-kernel data structures. Details can be found in the second link below. Fixes: 186b3c998c50 ("virtio-net: support XDP_REDIRECT") Signed-off-by: Magnus Karlsson Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/r/20221220185903.1105011-1-sbohrer@cloudflare.com Link: https://lore.kernel.org/all/20210624160609.292325-1-toke@redhat.com/ Acked-by: Michael S. Tsirkin --- drivers/net/virtio_net.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 18b3de854aeb..6df14dd5bf46 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1677,13 +1677,13 @@ static int virtnet_poll(struct napi_struct *napi, int budget) received = virtnet_receive(rq, budget, &xdp_xmit); + if (xdp_xmit & VIRTIO_XDP_REDIR) + xdp_do_flush(); + /* Out of packets? */ if (received < budget) virtqueue_napi_complete(napi, rq->vq, received); - if (xdp_xmit & VIRTIO_XDP_REDIR) - xdp_do_flush(); - if (xdp_xmit & VIRTIO_XDP_TX) { sq = virtnet_xdp_get_sq(vi); if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) { From patchwork Wed Jan 25 07:49:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Magnus Karlsson X-Patchwork-Id: 13115055 X-Patchwork-Delegate: kuba@kernel.org 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 56EA2C61D97 for ; Wed, 25 Jan 2023 07:49:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234999AbjAYHtZ (ORCPT ); Wed, 25 Jan 2023 02:49:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234420AbjAYHtW (ORCPT ); Wed, 25 Jan 2023 02:49:22 -0500 Received: from mail-wm1-x329.google.com (mail-wm1-x329.google.com [IPv6:2a00:1450:4864:20::329]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04A3C4A1D7; Tue, 24 Jan 2023 23:49:21 -0800 (PST) Received: by mail-wm1-x329.google.com with SMTP id j17so13107029wms.0; Tue, 24 Jan 2023 23:49:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=0wAglRLnbjA0GGYZd+Aa3Wz2YLS4ZzTlHhnzDb35wOY=; b=gFSKzeU5MBc7Jjp8JqZwhCje/VmhWMFRYBmMFP61AqJAbghIFyMHYYJ/uWmfn9rxa0 adQBxiNWRUz70ySJp+xYrDx4NO+UZHbKIYm4jpdmKQFlWWHBMQqd1xeCNAnx8kqSvzB7 jF0UvBuRaH1gkz0Pvx5brUInnmTTpbT+IN4UuO8duD9Iu+fnFAT0tO9TmHWwRU8XTb8g aXFKUyCxxs/2SCx7j35HLjd4FTT+miNGblqXGDDToqFFVch1Q5PTV3EACDeBiib2e4ep m6cgs37yg5Xs+yt3+C4uZ06KUvYvIFgI4kIlx2WfI1iS0Hn1M/QF4+A+AYd0w8/9Kf7N KNww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=0wAglRLnbjA0GGYZd+Aa3Wz2YLS4ZzTlHhnzDb35wOY=; b=SbSeYeSsaMA0ludrB7fb3+FMf6sx0Jl0Uifz2+HGwpGvQhNGC0iW0P6jvR3uNtxdlp xYbaAsS4IjRO0EdeuYowc3TmBFFlhQWiUOKEN3/DvbuFrXsdCYzp8tKOdUlHkMJWJcGW UAwenv9Ce1dmwm3rB1zxT28ogr7f1CniaNU1CUuGhsgrgf8Ja+13bChUE+p7FluqfI9t 2ng98QoTr6CF7hNaPLrTG/2InWoXZPfajHmmY5JNbANdzaG1xopRj1PCDKCvwxREuyDT BeLXJKtrKML8QF9D+00HRZU+PYhzdPq/z8ZSERM6sxY4PGlq+7w6gvWxuHolAdUHMp99 k1aw== X-Gm-Message-State: AFqh2kqpcymLoIIr8dEYO+vykR5Qk6F98Bw75/HRyRaXa+36u1BI8cBC +EELDG+pIYQJdmn/CnMt8E8= X-Google-Smtp-Source: AMrXdXvL2NOvrRkDpOrzbG9gYDVxdt0ZEqgut4lt6hzDdZyC39SJAIByD5LYIga/xz1SxgDIy6X0tQ== X-Received: by 2002:a05:600c:2d0b:b0:3da:fcf0:a31d with SMTP id x11-20020a05600c2d0b00b003dafcf0a31dmr30803951wmf.22.1674632959324; Tue, 24 Jan 2023 23:49:19 -0800 (PST) Received: from localhost.localdomain (h-176-10-254-193.A165.priv.bahnhof.se. [176.10.254.193]) by smtp.gmail.com with ESMTPSA id n13-20020a05600c500d00b003db2b81660esm1032051wmr.21.2023.01.24.23.49.17 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 24 Jan 2023 23:49:18 -0800 (PST) From: Magnus Karlsson To: magnus.karlsson@intel.com, bjorn@kernel.org, ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, jonathan.lemon@gmail.com, maciej.fijalkowski@intel.com, kuba@kernel.org, toke@redhat.com, pabeni@redhat.com, davem@davemloft.net, aelior@marvell.com, manishc@marvell.com, horatiu.vultur@microchip.com, UNGLinuxDriver@microchip.com, mst@redhat.com, jasowang@redhat.com, ioana.ciornei@nxp.com, madalin.bucur@nxp.com Cc: bpf@vger.kernel.org Subject: [PATCH net v2 4/5] dpaa_eth: execute xdp_do_flush() before napi_complete_done() Date: Wed, 25 Jan 2023 08:49:00 +0100 Message-Id: <20230125074901.2737-5-magnus.karlsson@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230125074901.2737-1-magnus.karlsson@gmail.com> References: <20230125074901.2737-1-magnus.karlsson@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Magnus Karlsson Make sure that xdp_do_flush() is always executed before napi_complete_done(). This is important for two reasons. First, a redirect to an XSKMAP assumes that a call to xdp_do_redirect() from napi context X on CPU Y will be followed by a xdp_do_flush() from the same napi context and CPU. This is not guaranteed if the napi_complete_done() is executed before xdp_do_flush(), as it tells the napi logic that it is fine to schedule napi context X on another CPU. Details from a production system triggering this bug using the veth driver can be found following the first link below. The second reason is that the XDP_REDIRECT logic in itself relies on being inside a single NAPI instance through to the xdp_do_flush() call for RCU protection of all in-kernel data structures. Details can be found in the second link below. Fixes: a1e031ffb422 ("dpaa_eth: add XDP_REDIRECT support") Signed-off-by: Magnus Karlsson Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/r/20221220185903.1105011-1-sbohrer@cloudflare.com Link: https://lore.kernel.org/all/20210624160609.292325-1-toke@redhat.com/ Acked-by: Camelia Groza --- drivers/net/ethernet/freescale/dpaa/dpaa_eth.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c b/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c index 3f8032947d86..027fff9f7db0 100644 --- a/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c +++ b/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c @@ -2410,6 +2410,9 @@ static int dpaa_eth_poll(struct napi_struct *napi, int budget) cleaned = qman_p_poll_dqrr(np->p, budget); + if (np->xdp_act & XDP_REDIRECT) + xdp_do_flush(); + if (cleaned < budget) { napi_complete_done(napi, cleaned); qman_p_irqsource_add(np->p, QM_PIRQ_DQRI); @@ -2417,9 +2420,6 @@ static int dpaa_eth_poll(struct napi_struct *napi, int budget) qman_p_irqsource_add(np->p, QM_PIRQ_DQRI); } - if (np->xdp_act & XDP_REDIRECT) - xdp_do_flush(); - return cleaned; } From patchwork Wed Jan 25 07:49:01 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Magnus Karlsson X-Patchwork-Id: 13115056 X-Patchwork-Delegate: kuba@kernel.org 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 539D2C61D97 for ; Wed, 25 Jan 2023 07:49:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235188AbjAYHtc (ORCPT ); Wed, 25 Jan 2023 02:49:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234946AbjAYHtY (ORCPT ); Wed, 25 Jan 2023 02:49:24 -0500 Received: from mail-wm1-x332.google.com (mail-wm1-x332.google.com [IPv6:2a00:1450:4864:20::332]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 954214C0DB; Tue, 24 Jan 2023 23:49:21 -0800 (PST) Received: by mail-wm1-x332.google.com with SMTP id f12-20020a7bc8cc000000b003daf6b2f9b9so617572wml.3; Tue, 24 Jan 2023 23:49:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=gMWF4QkdAYkP5DtCeyCWzEJa5WlqCRU1o+Xcs+ruoIw=; b=A+kxeUaMRFiXW1HX0VymZhnV85y3zT+s4IPbCjyVYunL2h3Sq6fbXCBuq1uh2sGLwP z+lCJkqVJMqgw+OxRvZcNfvQ8gDLDRHjyZgl8tikIgErLScd0Yur4VPgrq1Fjcu5rHzr uf2jLhHo/WnnJQiR9g1VIbrg3Qwp80m/Y2tFgTEKEQpLYCrf1F3kwnH7tFQKrP2KSxpV fdtPTTZQZSc5c8rN6Ic9OVlVN5MMMLE/Qawh2RDv662ttKibvm4vfhdLSWqjtJ4+22Hq pkqqLcOZzm4Kva788aCsWuyo3MnPhnj8RGkkMU12cK24ug3GpC+nzX0ULeVJkuQHoxnV jKkg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=gMWF4QkdAYkP5DtCeyCWzEJa5WlqCRU1o+Xcs+ruoIw=; b=sLkz1BLiu09qhuiWL+TgMSCsK+LVVZvNSm4vQ+ag7c+OX9lEQ/ZyTKBCotWI3PHvsp gifwDuHOQhFCUP62G2909HFh/fJJ+h7KxXQM9I85IrHTH3ftloi+CO9lQy3gIpbKM/oI 7K+VAg8Vf1oJ9HzTyk0739QaukVUM6aXt28BE+EpS3hWoy5S5++jl1PrQBc5EF1I5fFq BbKhVMaRRn1Xr/l8azlvR6L/ZL/oHZYHtNg/JxJnSoLfHTV3xN/IMeFgsrPO6yqnPe98 d9JuG711SkZytYqUKa08z36G7jevjpGmbUaPW4jz4TwAFqCgBigm0nBWTwSKR7KpRDQF n7dg== X-Gm-Message-State: AFqh2krUdXAbyM13wmkbuiP/Hk8GwE5assHmfiygDSfpAqtH+8ZkjfC6 jtwDR46pGzp6lwE0UDGqP0g= X-Google-Smtp-Source: AMrXdXuREyYFoE086geZVmDLLTSzLitLtbCRiU26bzUwgYdIa9nTnX0uyebjSQyzYvlhkIeJ12UG5g== X-Received: by 2002:a05:600c:1695:b0:3da:1c49:d632 with SMTP id k21-20020a05600c169500b003da1c49d632mr29959123wmn.1.1674632961166; Tue, 24 Jan 2023 23:49:21 -0800 (PST) Received: from localhost.localdomain (h-176-10-254-193.A165.priv.bahnhof.se. [176.10.254.193]) by smtp.gmail.com with ESMTPSA id n13-20020a05600c500d00b003db2b81660esm1032051wmr.21.2023.01.24.23.49.19 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 24 Jan 2023 23:49:20 -0800 (PST) From: Magnus Karlsson To: magnus.karlsson@intel.com, bjorn@kernel.org, ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, jonathan.lemon@gmail.com, maciej.fijalkowski@intel.com, kuba@kernel.org, toke@redhat.com, pabeni@redhat.com, davem@davemloft.net, aelior@marvell.com, manishc@marvell.com, horatiu.vultur@microchip.com, UNGLinuxDriver@microchip.com, mst@redhat.com, jasowang@redhat.com, ioana.ciornei@nxp.com, madalin.bucur@nxp.com Cc: bpf@vger.kernel.org Subject: [PATCH net v2 5/5] dpaa2-eth: execute xdp_do_flush() before napi_complete_done() Date: Wed, 25 Jan 2023 08:49:01 +0100 Message-Id: <20230125074901.2737-6-magnus.karlsson@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230125074901.2737-1-magnus.karlsson@gmail.com> References: <20230125074901.2737-1-magnus.karlsson@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Magnus Karlsson Make sure that xdp_do_flush() is always executed before napi_complete_done(). This is important for two reasons. First, a redirect to an XSKMAP assumes that a call to xdp_do_redirect() from napi context X on CPU Y will be followed by a xdp_do_flush() from the same napi context and CPU. This is not guaranteed if the napi_complete_done() is executed before xdp_do_flush(), as it tells the napi logic that it is fine to schedule napi context X on another CPU. Details from a production system triggering this bug using the veth driver can be found following the first link below. The second reason is that the XDP_REDIRECT logic in itself relies on being inside a single NAPI instance through to the xdp_do_flush() call for RCU protection of all in-kernel data structures. Details can be found in the second link below. Fixes: d678be1dc1ec ("dpaa2-eth: add XDP_REDIRECT support") Signed-off-by: Magnus Karlsson Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/r/20221220185903.1105011-1-sbohrer@cloudflare.com Link: https://lore.kernel.org/all/20210624160609.292325-1-toke@redhat.com/ --- drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c index 0c35abb7d065..2e79d18fc3c7 100644 --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c @@ -1993,10 +1993,15 @@ static int dpaa2_eth_poll(struct napi_struct *napi, int budget) if (rx_cleaned >= budget || txconf_cleaned >= DPAA2_ETH_TXCONF_PER_NAPI) { work_done = budget; + if (ch->xdp.res & XDP_REDIRECT) + xdp_do_flush(); goto out; } } while (store_cleaned); + if (ch->xdp.res & XDP_REDIRECT) + xdp_do_flush(); + /* Update NET DIM with the values for this CDAN */ dpaa2_io_update_net_dim(ch->dpio, ch->stats.frames_per_cdan, ch->stats.bytes_per_cdan); @@ -2032,9 +2037,7 @@ static int dpaa2_eth_poll(struct napi_struct *napi, int budget) txc_fq->dq_bytes = 0; } - if (ch->xdp.res & XDP_REDIRECT) - xdp_do_flush_map(); - else if (rx_cleaned && ch->xdp.res & XDP_TX) + if (rx_cleaned && ch->xdp.res & XDP_TX) dpaa2_eth_xdp_tx_flush(priv, ch, &priv->fq[flowid]); return work_done;