From patchwork Tue Apr 20 07:54:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: AceLan Kao X-Patchwork-Id: 425064 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1E50FC433ED for ; Tue, 20 Apr 2021 07:54:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D2D9861057 for ; Tue, 20 Apr 2021 07:54:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229913AbhDTHyw (ORCPT ); Tue, 20 Apr 2021 03:54:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229659AbhDTHym (ORCPT ); Tue, 20 Apr 2021 03:54:42 -0400 Received: from mail-pj1-x1034.google.com (mail-pj1-x1034.google.com [IPv6:2607:f8b0:4864:20::1034]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA3A4C06174A; Tue, 20 Apr 2021 00:54:09 -0700 (PDT) Received: by mail-pj1-x1034.google.com with SMTP id s14so14550286pjl.5; Tue, 20 Apr 2021 00:54:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:subject:date:message-id:mime-version :content-transfer-encoding; bh=Ke/YR/P2u+Tpx4KPA57i+VGmo9ckKXtimwr72CBdflY=; b=TBon4ejEdfyPf45ZQEv44fhDBiKbIyGGygqrFBMsj/lgNVefNCOh+s0hKnj36+Mr0S mq9w7FcnCcHT1xMjR2Fq6SBnXy9kbMBhKvoqBElLxM36FeQm3vZzQQv/QaVO75h3AsRV wgtUabWX8glAW9qLXLKzMH8W5Ib3HM4G2kjVDmg48lRWVL6s2tFuhTscnlxxThYw/+mK 5Ct1BMqAYPk0uJk4ob6bGQtSG3z+aSz8/tWfZyDtkOTAz60qCZy5oiyYApIQzLeYuYJR UrArmW4M+i2vbSD3oG1PtVPlov2EXGoJXwu6URIQu01OowbSEplwUF8W10tiYDCwGlEC IEZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:subject:date:message-id :mime-version:content-transfer-encoding; bh=Ke/YR/P2u+Tpx4KPA57i+VGmo9ckKXtimwr72CBdflY=; b=bCHLABcM554I67ALuH/JhGl5/GkmaOhO9WO8x4n0w1OVRh08dByTkBfOWaKJM7vVY7 9zFVgLw7D+Gf3tsjMPvvznUck6cU0E1XiEpDGSArIXnY9UuWIW2ugREM6vUxAIOiYhZ+ +vtYnY8Yoyw3RdYgklrEzuuq1E+T0rDszAwjiIo9MTWB/2O0o2KkFJwZzyVTvQdTMJvz yuxR8BDG8U1y7wB7SfxHyIyZFVlqbH4bWLDsViLCQo7U6mnDhOPqfLBhE+sYDOTMeYjj lA78hbUlQa5jNHfHVdWL+L48YBeH9VQ381DblbPSkWmknqbVuvyWy9M6W8FPWV/W3HVt M9jg== X-Gm-Message-State: AOAM530RpfjjIQaKgdaM9SsLqjaMlyTmQWRPMkA1Nm9hH1UNjcX6aTWR IunnpxcLON91mvcyHGd/MCo= X-Google-Smtp-Source: ABdhPJwd2xuyhLHRhZypxTgCkTxEfR4+k+OuBG25+iyBAE51EkqrPoKEdm1EfKWi5yrfSH039szw0Q== X-Received: by 2002:a17:90a:c8:: with SMTP id v8mr3617344pjd.18.1618905249046; Tue, 20 Apr 2021 00:54:09 -0700 (PDT) Received: from localhost (61-220-137-37.HINET-IP.hinet.net. [61.220.137.37]) by smtp.gmail.com with ESMTPSA id pc17sm528432pjb.19.2021.04.20.00.54.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 20 Apr 2021 00:54:07 -0700 (PDT) Sender: AceLan Kao From: AceLan Kao To: "David S. Miller" , Jakub Kicinski , Alexei Starovoitov , Andrii Nakryiko , Eric Dumazet , Wei Wang , Cong Wang , Taehee Yoo , =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] net: called rtnl_unlock() before runpm resumes devices Date: Tue, 20 Apr 2021 15:54:05 +0800 Message-Id: <20210420075406.64105-1-acelan.kao@canonical.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: "Chia-Lin Kao (AceLan)" The rtnl_lock() has been called in rtnetlink_rcv_msg(), and then in __dev_open() it calls pm_runtime_resume() to resume devices, and in some devices' resume function(igb_resum,igc_resume) they calls rtnl_lock() again. That leads to a recursive lock. It should leave the devices' resume function to decide if they need to call rtnl_lock()/rtnl_unlock(), so call rtnl_unlock() before calling pm_runtime_resume() and then call rtnl_lock() after it in __dev_open(). [ 967.723577] INFO: task ip:6024 blocked for more than 120 seconds. [ 967.723588] Not tainted 5.12.0-rc3+ #1 [ 967.723592] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 967.723594] task:ip state:D stack: 0 pid: 6024 ppid: 5957 flags:0x00004000 [ 967.723603] Call Trace: [ 967.723610] __schedule+0x2de/0x890 [ 967.723623] schedule+0x4f/0xc0 [ 967.723629] schedule_preempt_disabled+0xe/0x10 [ 967.723636] __mutex_lock.isra.0+0x190/0x510 [ 967.723644] __mutex_lock_slowpath+0x13/0x20 [ 967.723651] mutex_lock+0x32/0x40 [ 967.723657] rtnl_lock+0x15/0x20 [ 967.723665] igb_resume+0xee/0x1d0 [igb] [ 967.723687] ? pci_pm_default_resume+0x30/0x30 [ 967.723696] igb_runtime_resume+0xe/0x10 [igb] [ 967.723713] pci_pm_runtime_resume+0x74/0x90 [ 967.723718] __rpm_callback+0x53/0x1c0 [ 967.723725] rpm_callback+0x57/0x80 [ 967.723730] ? pci_pm_default_resume+0x30/0x30 [ 967.723735] rpm_resume+0x547/0x760 [ 967.723740] __pm_runtime_resume+0x52/0x80 [ 967.723745] __dev_open+0x56/0x160 [ 967.723753] ? _raw_spin_unlock_bh+0x1e/0x20 [ 967.723758] __dev_change_flags+0x188/0x1e0 [ 967.723766] dev_change_flags+0x26/0x60 [ 967.723773] do_setlink+0x723/0x10b0 [ 967.723782] ? __nla_validate_parse+0x5b/0xb80 [ 967.723792] __rtnl_newlink+0x594/0xa00 [ 967.723800] ? nla_put_ifalias+0x38/0xa0 [ 967.723807] ? __nla_reserve+0x41/0x50 [ 967.723813] ? __nla_reserve+0x41/0x50 [ 967.723818] ? __kmalloc_node_track_caller+0x49b/0x4d0 [ 967.723824] ? pskb_expand_head+0x75/0x310 [ 967.723830] ? nla_reserve+0x28/0x30 [ 967.723835] ? skb_free_head+0x25/0x30 [ 967.723843] ? security_sock_rcv_skb+0x2f/0x50 [ 967.723850] ? netlink_deliver_tap+0x3d/0x210 [ 967.723859] ? sk_filter_trim_cap+0xc1/0x230 [ 967.723863] ? skb_queue_tail+0x43/0x50 [ 967.723870] ? sock_def_readable+0x4b/0x80 [ 967.723876] ? __netlink_sendskb+0x42/0x50 [ 967.723888] ? security_capable+0x3d/0x60 [ 967.723894] ? __cond_resched+0x19/0x30 [ 967.723900] ? kmem_cache_alloc_trace+0x390/0x440 [ 967.723906] rtnl_newlink+0x49/0x70 [ 967.723913] rtnetlink_rcv_msg+0x13c/0x370 [ 967.723920] ? _copy_to_iter+0xa0/0x460 [ 967.723927] ? rtnl_calcit.isra.0+0x130/0x130 [ 967.723934] netlink_rcv_skb+0x55/0x100 [ 967.723939] rtnetlink_rcv+0x15/0x20 [ 967.723944] netlink_unicast+0x1a8/0x250 [ 967.723949] netlink_sendmsg+0x233/0x460 [ 967.723954] sock_sendmsg+0x65/0x70 [ 967.723958] ____sys_sendmsg+0x218/0x290 [ 967.723961] ? copy_msghdr_from_user+0x5c/0x90 [ 967.723966] ? lru_cache_add_inactive_or_unevictable+0x27/0xb0 [ 967.723974] ___sys_sendmsg+0x81/0xc0 [ 967.723980] ? __mod_memcg_lruvec_state+0x22/0xe0 [ 967.723987] ? kmem_cache_free+0x244/0x420 [ 967.723991] ? dentry_free+0x37/0x70 [ 967.723996] ? mntput_no_expire+0x4c/0x260 [ 967.724001] ? __cond_resched+0x19/0x30 [ 967.724007] ? security_file_free+0x54/0x60 [ 967.724013] ? call_rcu+0xa4/0x250 [ 967.724021] __sys_sendmsg+0x62/0xb0 [ 967.724026] ? exit_to_user_mode_prepare+0x3d/0x1a0 [ 967.724032] __x64_sys_sendmsg+0x1f/0x30 [ 967.724037] do_syscall_64+0x38/0x90 [ 967.724044] entry_SYSCALL_64_after_hwframe+0x44/0xae Signed-off-by: Chia-Lin Kao (AceLan) --- net/core/dev.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/core/dev.c b/net/core/dev.c index 1f79b9aa9a3f..427cbc80d1e5 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1537,8 +1537,11 @@ static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack) if (!netif_device_present(dev)) { /* may be detached because parent is runtime-suspended */ - if (dev->dev.parent) + if (dev->dev.parent) { + rtnl_unlock(); pm_runtime_resume(dev->dev.parent); + rtnl_lock(); + } if (!netif_device_present(dev)) return -ENODEV; }