From patchwork Wed Aug 5 07:19:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tonghao Zhang X-Patchwork-Id: 1341125 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=ilW8vnnJ; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4BM30q4fhvz9sPB for ; Wed, 5 Aug 2020 17:19:55 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728034AbgHEHTv (ORCPT ); Wed, 5 Aug 2020 03:19:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43358 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725904AbgHEHTt (ORCPT ); Wed, 5 Aug 2020 03:19:49 -0400 Received: from mail-qk1-x743.google.com (mail-qk1-x743.google.com [IPv6:2607:f8b0:4864:20::743]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3287DC06174A; Wed, 5 Aug 2020 00:19:49 -0700 (PDT) Received: by mail-qk1-x743.google.com with SMTP id p25so332206qkp.2; Wed, 05 Aug 2020 00:19:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=FaEGzOgyBR8AMrEH/saCACEjpxQkzKeYijkuZ/V+U+o=; b=ilW8vnnJJfaLmaAF552XrtvQJaLxZzmJQYy9RZXrp9+zWxJSn7ZBqnocioKgTZD7di M+gu5qpz8NGmWu8e5WFOIHch8DUejIzqTm4RA9XDm7qvF3qd0onAuG1HvZBA81ykTbe8 ALSOyP42Da9aX1NBhuS99F4K8XEkal3QwiTCBi+OO2ud8gAvin9ReEiDk82Qw8/5+23h wi3ydf7gcOvfCey581GZTctje7xG35/DzCuxRGmvSmtSn2w02SGHDAtvtkMGjwq5lYI1 OT0qk1uFZY66uxVv9UUw47h2Yd7BWoAXTsMJCg1/gS+Dzhu5FEimycK/4tNaOU7UR9Sn Qulw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=FaEGzOgyBR8AMrEH/saCACEjpxQkzKeYijkuZ/V+U+o=; b=n8h5oCPrw2lWN63UXVsdn28ANbQ6UMhJZfepC97oCvVJQZTh5X/7xO8V6QD+XOeSBJ j9sOgxiAkhVaKBA5N/C+xA19jaOJKJ3pztmucp0y8TV1UaSs4JnJr/OoSti+tpR9A+7l qmicFC3E/CrYsZG3wiDNCs/2zoA33D0k22igu7V43enTllfazC6c6YYK9ipe0TlikniM 91gokPJ1QgLwyEbWvdA35X1z+yjwwK95nU317IdLwDPK6ceJsXT4ZXB7mOudjKMAczJ4 HCK2gHK1a+W/0dojAWNk3hfVVlp5g7pSBWbMvW7Rka3Jk5POz5Ri8t6zAbW1hKwZmQc1 9jeg== X-Gm-Message-State: AOAM533la/Stk8MxOAhalJS1xH7VOZnvXodWJt9EIZp9JNchLqi9Suc6 Xj/v6Bv/2Bq+4xQLOziOkuA= X-Google-Smtp-Source: ABdhPJxTwbNbMDnDvBuxSOb/SHAzcUaYN56CL+kG8AQqLnCQWcOsXUp0JwT+Hecp1bNzf8wZlGuGcw== X-Received: by 2002:a05:620a:490:: with SMTP id 16mr1848131qkr.89.1596611988431; Wed, 05 Aug 2020 00:19:48 -0700 (PDT) Received: from localhost.localdomain ([111.205.198.3]) by smtp.gmail.com with ESMTPSA id y14sm1389009qtc.84.2020.08.05.00.19.43 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 05 Aug 2020 00:19:47 -0700 (PDT) From: xiangxia.m.yue@gmail.com To: davem@davemloft.net, echaudro@redhat.com, kuba@kernel.org, pabeni@redhat.com, pshelar@ovn.org, syzkaller-bugs@googlegroups.com Cc: dev@openvswitch.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Tonghao Zhang Subject: [PATCH] net: openvswitch: silence suspicious RCU usage warning Date: Wed, 5 Aug 2020 15:19:11 +0800 Message-Id: <20200805071911.64101-1-xiangxia.m.yue@gmail.com> X-Mailer: git-send-email 2.15.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Tonghao Zhang ovs_flow_tbl_destroy always is called from RCU callback or error path. It is no need to check if rcu_read_lock or lockdep_ovsl_is_held was held. ovs_dp_cmd_fill_info always is called with ovs_mutex, So use the rcu_dereference_ovsl instead of rcu_dereference in ovs_flow_tbl_masks_cache_size. Fixes: 9bf24f594c6a ("net: openvswitch: make masks cache size configurable") Cc: Eelco Chaudron Reported-by: syzbot+c0eb9e7cdde04e4eb4be@syzkaller.appspotmail.com Reported-by: syzbot+f612c02823acb02ff9bc@syzkaller.appspotmail.com Signed-off-by: Tonghao Zhang Acked-by: Paolo Abeni --- net/openvswitch/flow_table.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c index 6527d84c3ea6..8c12675cbb67 100644 --- a/net/openvswitch/flow_table.c +++ b/net/openvswitch/flow_table.c @@ -518,8 +518,8 @@ void ovs_flow_tbl_destroy(struct flow_table *table) { struct table_instance *ti = rcu_dereference_raw(table->ti); struct table_instance *ufid_ti = rcu_dereference_raw(table->ufid_ti); - struct mask_cache *mc = rcu_dereference(table->mask_cache); - struct mask_array *ma = rcu_dereference_ovsl(table->mask_array); + struct mask_cache *mc = rcu_dereference_raw(table->mask_cache); + struct mask_array *ma = rcu_dereference_raw(table->mask_array); call_rcu(&mc->rcu, mask_cache_rcu_cb); call_rcu(&ma->rcu, mask_array_rcu_cb); @@ -937,7 +937,7 @@ int ovs_flow_tbl_num_masks(const struct flow_table *table) u32 ovs_flow_tbl_masks_cache_size(const struct flow_table *table) { - struct mask_cache *mc = rcu_dereference(table->mask_cache); + struct mask_cache *mc = rcu_dereference_ovsl(table->mask_cache); return READ_ONCE(mc->cache_size); }