From mboxrd@z Thu Jan 1 00:00:00 1970 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=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 A55F4C433EF for ; Fri, 10 Sep 2021 01:57:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 818086115A for ; Fri, 10 Sep 2021 01:57:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229606AbhIJB6S (ORCPT ); Thu, 9 Sep 2021 21:58:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59870 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229445AbhIJB6R (ORCPT ); Thu, 9 Sep 2021 21:58:17 -0400 Received: from mail-ed1-x52b.google.com (mail-ed1-x52b.google.com [IPv6:2a00:1450:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 24A7FC061574 for ; Thu, 9 Sep 2021 18:57:07 -0700 (PDT) Received: by mail-ed1-x52b.google.com with SMTP id n10so218662eda.10 for ; Thu, 09 Sep 2021 18:57:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=JH8z0gfC7SVIjJQM/dDZRtueKMl+/4hR7khpIn55knw=; b=QXbz8Mn4MiAGy+jwu9xji5yeGIyrPJQcTWz+3rYbak2w1QaFdohRByURdihvfEnJbQ 6gGAC3RBeBInUkHFsDQ0JT/OszdRL+F+xl3n2lsrUY6a25Lmp1NzUgT9vI/F/j7KCNr6 qToK3um4Mf90qs89K0gPoIbuGANYyWIOe0RWaPBRb2ce/XKotFjingy9N6Ps+hl6m/qt r04Mne6Bv9hhi3m0s2PBaeyV/zOxEScP1F+COKMHUjFavf01tI6qvtusdumJ0eQ/nMLY KYJXlQ59sessSMtv/LZuHesctEdqM5z1N1HlguILt420tMdvfDjA0CEIsrMjbr+V/5Cw ojHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=JH8z0gfC7SVIjJQM/dDZRtueKMl+/4hR7khpIn55knw=; b=bB5SyHQW7Dj26qE8jbV2IUv9Qm+lNPe2p3MdVvgMrTaGncXVTrpf2cwPJWnZJS+XvG 1D5Y2PeFFIRXe7KSrOxAYFnGI6zVFYPkdCwMFDyTmIIsuQ9nD2+W4FgAJt/xzt9lOxyl SSI/rCIB2j30oFSwT4SnB+EpDwXEon4YomMBLDIPqEDuEONxq04vGZ3AXyo1qbOTN5BV tR/aNdb41qyz29iqqdDafCHQ8AB01qP42N1iqJfc5JVhEFyQCHkNrVnhpGr1bdFDpahd mvx1yJCL1f1jta4OqKYmSNlOKPopojUmSwswdVGa+gr5tj3vem7T65UHyYWmJ7hkINES Hdkw== X-Gm-Message-State: AOAM532NnM9xpMkRpNBbnf8j/8oOW+8DmTTBoV8atXDJ4ZhMaRoq9NKK jOXbIneVXJ5MktrradDs1bU= X-Google-Smtp-Source: ABdhPJwPZzLVlyjuLNB2fB8d1Pyev/bzpkixzgN7Jdwl6mzVdGHcs3pLM6JRZiliETM/RafFIwHD4w== X-Received: by 2002:a05:6402:27c6:: with SMTP id c6mr6340064ede.111.1631239025499; Thu, 09 Sep 2021 18:57:05 -0700 (PDT) Received: from smtpclient.apple ([178.254.237.20]) by smtp.gmail.com with ESMTPSA id h2sm1896087edd.43.2021.09.09.18.57.04 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 09 Sep 2021 18:57:04 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.120.0.1.13\)) Subject: Re: [PATCH net v4] net: fix race between napi kthread mode and busy poll From: Martin Zaharinov In-Reply-To: Date: Fri, 10 Sep 2021 04:57:03 +0300 Cc: Eric Dumazet , "David S . Miller" , Jakub Kicinski , netdev , Alexander Duyck , Paolo Abeni , Hannes Frederic Sowa , Greg KH Content-Transfer-Encoding: quoted-printable Message-Id: <3E85950C-35E8-4169-89B3-3C59E65281D6@gmail.com> References: <20210316223647.4080796-1-weiwan@google.com> <6AF20AA6-07E7-4DDD-8A9E-BE093FC03802@gmail.com> <6129CBF0-4418-43C8-A2F1-359972D8B809@gmail.com> To: Wei Wang X-Mailer: Apple Mail (2.3654.120.0.1.13) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi Wei, The problem is hard to reproduce. I see for second time this problem in = a period of 1 month. Server use for Firewall/NAT/PPPOE and have connect users to machine. cat /proc/sys/net/core/busy_poll - 50 cat /proc/sys/net/core/busy_read - 50 cat /sys/class/net/eth0/threaded - 1 cat /sys/class/net/eth1/threaded - 1=20 May be not use SO_PREFER_BUSY_POLL - how to check and enable? P.S. Eth0 and eth1 united in one common teamd/bond=20 Best regards, Martin > On 10 Sep 2021, at 3:30, Wei Wang wrote: >=20 > Hi Martin, >=20 > Is there a reproducer for this? What kind of traffic is it running? > What is the following config: > cat /proc/sys/net/core/busy_poll > cat /proc/sys/net/core/busy_read > cat /sys/class/net//threaded > And is SO_PREFER_BUSY_POLL used? >=20 > Thanks. > Wei >=20 >=20 >=20 > On Thu, Sep 9, 2021 at 4:18 AM Martin Zaharinov = wrote: >>=20 >> Hi Eric and Wei >>=20 >> Please see this bug report from last hour , >> Kernel 5.13.13, Traffic is 7Gb/s down/ 7Gb/s up >> Uptime before crash : 10day >>=20 >>=20 >>=20 >>=20 >> Sep 9 12:49:31 [829553.899833][ T2925] ------------[ cut here = ]------------ >> Sep 9 12:49:31 [829553.927316][ T2925] list_del corruption. = next->prev should be ffff9651016c0b00, but was ffff96511a87c158 >> Sep 9 12:49:31 [829553.981630][ T2925] WARNING: CPU: 3 PID: 2925 at = lib/list_debug.c:54 __list_del_entry_valid+0x8a/0x90 >> Sep 9 12:49:31 [829554.035795][ T2925] Modules linked in: xsk_diag = unix_diag nf_conntrack_netlink nfnetlink vlan_mon(O) pppoe pppox = ppp_generic slhc team_mode_loadbalance team xt_MASQUERADE xt_nat = iptable_nat xt_TCPMSS xt_comment iptable_mangle ip_tables netconsole = coretemp ixgbe mdio mdio_devres libphy nf_nat_sip nf_conntrack_sip = nf_nat_pptp nf_conntrack_pptp nf_nat_tftp nf_conntrack_tftp nf_nat_ftp = nf_conntrack_ftp nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 = nf_xnatlog(O) acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler rtc_cmos = [last unloaded: iptable_raw] >> Sep 9 12:49:31 [829554.254022][ T2925] CPU: 3 PID: 2925 Comm: kresd = Tainted: G O 5.13.13 #1 >> Sep 9 12:49:31 [829554.307304][ T2925] Hardware name: Supermicro = Super Server/X10SRD-F, BIOS 3.3 10/28/2020 >> Sep 9 12:49:31 [829554.360188][ T2925] RIP: = 0010:__list_del_entry_valid+0x8a/0x90 >> Sep 9 12:49:31 [829554.386671][ T2925] Code: 46 00 0f 0b 31 c0 c3 = 48 89 f2 48 89 fe 48 c7 c7 40 33 16 9a e8 0b 69 46 00 0f 0b 31 c0 c3 48 = c7 c7 80 33 16 9a e8 fa 68 46 00 <0f> 0b 31 c0 c3 cc 89 f8 48 85 d2 74 = 1f 48 01 f2 0f b6 0e 48 ff c6 >> Sep 9 12:49:31 [829554.465378][ T2925] RSP: 0018:ffffa90ec1affd00 = EFLAGS: 00010286 >> Sep 9 12:49:31 [829554.491219][ T2925] RAX: 0000000000000054 RBX: = ffff9651016c0a00 RCX: 0000000000000001 >> Sep 9 12:49:32 [829554.541672][ T2925] RDX: 00000000ffffffea RSI: = 00000000fffbffff RDI: 00000000fffbffff >> Sep 9 12:49:32 [829554.592016][ T2925] RBP: ffff96511a87c158 R08: = 0000000000000001 R09: 00000000fffbffff >> Sep 9 12:49:32 [829554.642131][ T2925] R10: ffff96546d600000 R11: = ffffa90ec1affb50 R12: ffff9651016c0b00 >> Sep 9 12:49:32 [829554.692890][ T2925] R13: 0000000000000008 R14: = ffffa90ec1affd20 R15: ffff9651016c0b00 >> Sep 9 12:49:32 [829554.744221][ T2925] FS: 00007f38717a5900(0000) = GS:ffff96546fac0000(0000) knlGS:0000000000000000 >> Sep 9 12:49:32 [829554.795701][ T2925] CS: 0010 DS: 0000 ES: 0000 = CR0: 0000000080050033 >> Sep 9 12:49:32 [829554.821598][ T2925] CR2: 00007f3854c0a000 CR3: = 0000000115a7c001 CR4: 00000000001706e0 >> Sep 9 12:49:32 [829554.872045][ T2925] DR0: 0000000000000000 DR1: = 0000000000000000 DR2: 0000000000000000 >> Sep 9 12:49:32 [829554.922284][ T2925] DR3: 0000000000000000 DR6: = 00000000fffe0ff0 DR7: 0000000000000400 >> Sep 9 12:49:32 [829554.972250][ T2925] Call Trace: >> Sep 9 12:49:32 [829554.996597][ T2925] = netif_receive_skb_list_internal+0x25c/0x2b0 >> Sep 9 12:49:32 [829555.021270][ T2925] busy_poll_stop+0x113/0x140 >> Sep 9 12:49:32 [829555.045679][ T2925] ? = ep_destroy_wakeup_source+0x20/0x20 >> Sep 9 12:49:32 [829555.069833][ T2925] ? = ixgbe_clean_rx_irq+0x790/0x790 [ixgbe] >> Sep 9 12:49:32 [829555.093659][ T2925] napi_busy_loop+0x212/0x280 >> Sep 9 12:49:32 [829555.117046][ T2925] ep_poll+0xba/0x380 >> Sep 9 12:49:32 [829555.140048][ T2925] ? __napi_poll+0x1f/0x100 >> Sep 9 12:49:32 [829555.162477][ T2925] do_epoll_wait+0xa6/0xc0 >> Sep 9 12:49:32 [829555.184504][ T2925] = do_epoll_pwait.part.0+0x9/0x70 >> Sep 9 12:49:32 [829555.206138][ T2925] = __x64_sys_epoll_pwait+0x6a/0x100 >> Sep 9 12:49:32 [829555.227619][ T2925] ? do_syscall_64+0x3a/0x70 >> Sep 9 12:49:32 [829555.248592][ T2925] ? = entry_SYSCALL_64_after_hwframe+0x44/0xae >> Sep 9 12:49:32 [829555.269414][ T2925] ---[ end trace = 7792cf332872df55 ]--- >> Sep 9 12:49:32 [829555.317238][ T2925] BUG: unable to handle page = fault for address: 00000000000496c9 >> Sep 9 12:49:32 [829555.357231][ T2925] #PF: supervisor read access = in kernel mode >> Sep 9 12:49:32 [829555.377314][ T2925] #PF: error_code(0x0000) - = not-present page >> Sep 9 12:49:32 [829555.396972][ T2925] PGD 12ad0f067 P4D 12ad0f067 = PUD 12ad11067 PMD 0 >> Sep 9 12:49:32 [829555.416441][ T2925] Oops: 0000 [#1] SMP NOPTI >> Sep 9 12:49:32 [829555.435328][ T2925] CPU: 3 PID: 2925 Comm: kresd = Tainted: G W O 5.13.13 #1 >> Sep 9 12:49:32 [829555.472060][ T2925] Hardware name: Supermicro = Super Server/X10SRD-F, BIOS 3.3 10/28/2020 >> Sep 9 12:49:32 [829555.508998][ T2925] RIP: = 0010:get_rps_cpu+0x1b/0x2f0 >> Sep 9 12:49:33 [829555.527449][ T2925] Code: 0f 0b e8 28 e7 1b 00 = 0f 1f 84 00 00 00 00 00 41 57 41 56 49 89 d6 41 55 49 89 fd 41 54 55 48 = 89 f5 53 48 83 ec 20 0f b7 56 7c <48> 8b 87 e8 02 00 00 66 85 d2 74 1f = ff ca 0f b7 ca 44 8b 87 f4 02 >> Sep 9 12:49:33 [829555.582511][ T2925] RSP: 0018:ffffa90ec1affcb0 = EFLAGS: 00010282 >> Sep 9 12:49:33 [829555.600509][ T2925] RAX: ffff9651847be000 RBX: = ffff9651847be000 RCX: 0000000000200015 >> Sep 9 12:49:33 [829555.636779][ T2925] RDX: 0000000000009654 RSI: = ffff96546fae26f8 RDI: 00000000000493e1 >> Sep 9 12:49:33 [829555.674280][ T2925] RBP: ffff96546fae26f8 R08: = 0000000000000001 R09: ffff96519f7f1900 >> Sep 9 12:49:33 [829555.713363][ T2925] R10: 0000000000000000 R11: = 00000000000262c8 R12: ffff96546fae26f8 >> Sep 9 12:49:33 [829555.754362][ T2925] R13: 00000000000493e1 R14: = ffffa90ec1affd08 R15: ffff96546fae26f8 >> Sep 9 12:49:33 [829555.797754][ T2925] FS: 00007f38717a5900(0000) = GS:ffff96546fac0000(0000) knlGS:0000000000000000 >> Sep 9 12:49:33 [829555.843229][ T2925] CS: 0010 DS: 0000 ES: 0000 = CR0: 0000000080050033 >> Sep 9 12:49:33 [829555.866726][ T2925] CR2: 00000000000496c9 CR3: = 0000000115a7c001 CR4: 00000000001706e0 >> Sep 9 12:49:33 [829555.913285][ T2925] DR0: 0000000000000000 DR1: = 0000000000000000 DR2: 0000000000000000 >> Sep 9 12:49:33 [829555.960278][ T2925] DR3: 0000000000000000 DR6: = 00000000fffe0ff0 DR7: 0000000000000400 >> Sep 9 12:49:33 [829556.008563][ T2925] Call Trace: >> Sep 9 12:49:33 [829556.032547][ T2925] ? = enqueue_to_backlog+0x81/0x250 >> Sep 9 12:49:33 [829556.056686][ T2925] = netif_receive_skb_list_internal+0x24d/0x2b0 >> Sep 9 12:49:33 [829556.080870][ T2925] busy_poll_stop+0x113/0x140 >> Sep 9 12:49:33 [829556.104559][ T2925] ? = ep_destroy_wakeup_source+0x20/0x20 >> Sep 9 12:49:33 [829556.128028][ T2925] ? = ixgbe_clean_rx_irq+0x790/0x790 [ixgbe] >> Sep 9 12:49:33 [829556.151405][ T2925] napi_busy_loop+0x212/0x280 >> Sep 9 12:49:33 [829556.174478][ T2925] ep_poll+0xba/0x380 >> Sep 9 12:49:33 [829556.196887][ T2925] ? __napi_poll+0x1f/0x100 >> Sep 9 12:49:33 [829556.219070][ T2925] do_epoll_wait+0xa6/0xc0 >> Sep 9 12:49:33 [829556.240778][ T2925] = do_epoll_pwait.part.0+0x9/0x70 >> Sep 9 12:49:33 [829556.262203][ T2925] = __x64_sys_epoll_pwait+0x6a/0x100 >> Sep 9 12:49:33 [829556.283188][ T2925] ? do_syscall_64+0x3a/0x70 >> Sep 9 12:49:33 [829556.303666][ T2925] ? = entry_SYSCALL_64_after_hwframe+0x44/0xae >> Sep 9 12:49:33 [829556.323995][ T2925] Modules linked in: xsk_diag = unix_diag nf_conntrack_netlink nfnetlink vlan_mon(O) pppoe pppox = ppp_generic slhc team_mode_loadbalance team xt_MASQUERADE xt_nat = iptable_nat xt_TCPMSS xt_comment iptable_mangle ip_tables netconsole = coretemp ixgbe mdio mdio_devres libphy nf_nat_sip nf_conntrack_sip = nf_nat_pptp nf_conntrack_pptp nf_nat_tftp nf_conntrack_tftp nf_nat_ftp = nf_conntrack_ftp nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 = nf_xnatlog(O) acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler rtc_cmos = [last unloaded: iptable_raw] >> Sep 9 12:49:33 [829556.487037][ T2925] CR2: 00000000000496c9 >> Sep 9 12:49:33 [829556.507006][ T2925] ---[ end trace = 7792cf332872df56 ]--- >> Sep 9 12:49:33 [829556.526984][ T2925] RIP: = 0010:get_rps_cpu+0x1b/0x2f0 >> Sep 9 12:49:34 [829556.546524][ T2925] Code: 0f 0b e8 28 e7 1b 00 = 0f 1f 84 00 00 00 00 00 41 57 41 56 49 89 d6 41 55 49 89 fd 41 54 55 48 = 89 f5 53 48 83 ec 20 0f b7 56 7c <48> 8b 87 e8 02 00 00 66 85 d2 74 1f = ff ca 0f b7 ca 44 8b 87 f4 02 >> Sep 9 12:49:34 [829556.604787][ T2925] RSP: 0018:ffffa90ec1affcb0 = EFLAGS: 00010282 >> Sep 9 12:49:34 [829556.623841][ T2925] RAX: ffff9651847be000 RBX: = ffff9651847be000 RCX: 0000000000200015 >> Sep 9 12:49:34 [829556.662385][ T2925] RDX: 0000000000009654 RSI: = ffff96546fae26f8 RDI: 00000000000493e1 >> Sep 9 12:49:34 [829556.702267][ T2925] RBP: ffff96546fae26f8 R08: = 0000000000000001 R09: ffff96519f7f1900 >> Sep 9 12:49:34 [829556.743605][ T2925] R10: 0000000000000000 R11: = 00000000000262c8 R12: ffff96546fae26f8 >> Sep 9 12:49:34 [829556.786604][ T2925] R13: 00000000000493e1 R14: = ffffa90ec1affd08 R15: ffff96546fae26f8 >> Sep 9 12:49:34 [829556.831749][ T2925] FS: 00007f38717a5900(0000) = GS:ffff96546fac0000(0000) knlGS:0000000000000000 >> Sep 9 12:49:34 [829556.879295][ T2925] CS: 0010 DS: 0000 ES: 0000 = CR0: 0000000080050033 >> Sep 9 12:49:34 [829556.903908][ T2925] CR2: 00000000000496c9 CR3: = 0000000115a7c001 CR4: 00000000001706e0 >> Sep 9 12:49:34 [829556.952783][ T2925] DR0: 0000000000000000 DR1: = 0000000000000000 DR2: 0000000000000000 >> Sep 9 12:49:34 [829557.001612][ T2925] DR3: 0000000000000000 DR6: = 00000000fffe0ff0 DR7: 0000000000000400 >> Sep 9 12:49:34 [829557.050193][ T2925] Kernel panic - not syncing: = Fatal exception in interrupt >> Sep 9 12:49:34 [829557.182948][ T2925] Kernel Offset: 0x18000000 = from 0xffffffff81000000 (relocation range: = 0xffffffff80000000-0xffffffffbfffffff) >> Sep 9 12:49:34 [829557.231174][ T2925] Rebooting in 10 seconds.. >> Sep 9 12:49:44 [829567.255206][ T2925] ACPI MEMORY or I/O = RESET_REG. >>=20 >>> On 30 Mar 2021, at 16:39, Eric Dumazet wrote: >>>=20 >>> On Tue, Mar 30, 2021 at 11:25 AM Martin Zaharinov = wrote: >>>>=20 >>>> Hi Eric and Wei >>>>=20 >>>> Please check this log : >>>>=20 >>>=20 >>> Please send a normal report to netdev. >>>=20 >>> This has nothing to to with us (Eric & Wei) >>>=20 >>> Thanks. >>>=20 >>>>=20 >>>> 1584288.951272] napi/eth0-523: page allocation failure: order:0, = mode:0x40a20(GFP_ATOMIC|__GFP_COMP), nodemask=3D(null) >>>> [1584289.003674] CPU: 4 PID: 3179 Comm: napi/eth0-523 Tainted: G = O 5.11.4 #1 >>>> [1584289.055545] Hardware name: Supermicro = SYS-5038MR-H8TRF/X10SRD-F, BIOS 3.2 11/22/2019 >>>> [1584289.107263] Call Trace: >>>> [1584289.107266] dump_stack+0x58/0x6b >>>> [1584289.209562] warn_alloc.cold+0x70/0xd4 >>>> [1584289.209569] __alloc_pages_slowpath.constprop.0+0xd57/0xfb0 >>>> [1584289.209574] __alloc_pages_nodemask+0x15a/0x180 >>>> [1584289.474009] allocate_slab+0x272/0x450 >>>> [1584289.496731] ___slab_alloc.constprop.0+0x41e/0x4d0 >>>> [1584289.519147] kmem_cache_alloc+0x110/0x120 >>>> [1584289.541416] build_skb+0x1a/0x200 >>>> [1584289.563121] ixgbe_clean_rx_irq+0x5fc/0xa10 [ixgbe] >>>> [1584289.584618] ixgbe_poll+0xeb/0x2a0 [ixgbe] >>>> [1584289.605528] __napi_poll+0x1f/0x130 >>>> [1584289.625842] napi_threaded_poll+0x110/0x160 >>>> [1584289.646110] ? __napi_poll+0x130/0x130 >>>> [1584289.665810] kthread+0xea/0x120 >>>> [1584289.684836] ? kthread_park+0x80/0x80 >>>> [1584289.703440] ret_from_fork+0x1f/0x30 >>>> [1584289.721616] Mem-Info: >>>> [1584289.739066] active_anon:8157 inactive_anon:2100191 = isolated_anon:0 >>>> active_file:17408 inactive_file:149 = isolated_file:32 >>>> unevictable:1440359 dirty:17500 writeback:0 >>>> slab_reclaimable:43368 slab_unreclaimable:155124 >>>> mapped:817431 shmem:7650 pagetables:32093 bounce:0 >>>> free:17832 free_pcp:113 free_cma:0 >>>> [1584289.842614] Node 0 active_anon:32628kB inactive_anon:8400764kB = active_file:69312kB inactive_file:880kB unevictable:5761436kB = isolated(anon):0kB isolated(file):128kB mapped:3269724kB dirty:69740kB = writeback:0kB shmem:30600kB writeback_tmp:0kB kernel_stack:5376kB = pagetables:128372kB all_unreclaimable? no >>>> [1584289.913793] Node 0 DMA free:13836kB min:12kB low:24kB = high:36kB reserved_highatomic:0KB active_anon:0kB inactive_anon:0kB = active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB = present:15968kB managed:15884kB mlocked:0kB bounce:0kB free_pcp:0kB = local_pcp:0kB free_cma:0kB >>>> [1584289.986882] lowmem_reserve[]: 0 1741 15726 15726 >>>> [1584290.005519] Node 0 DMA32 free:54448kB min:9780kB low:11560kB = high:13340kB reserved_highatomic:24576KB active_anon:5104kB = inactive_anon:760844kB active_file:51532kB inactive_file:388kB = unevictable:885428kB writepending:51744kB present:1965124kB = managed:1899588kB mlocked:0kB bounce:0kB free_pcp:684kB local_pcp:0kB = free_cma:0kB >>>> [1584290.104980] lowmem_reserve[]: 0 0 13985 13985 >>>> [1584290.125807] Node 0 Normal free:2288kB min:78608kB low:92928kB = high:107248kB reserved_highatomic:32768KB active_anon:27524kB = inactive_anon:7639920kB active_file:17776kB inactive_file:1304kB = unevictable:4876016kB writepending:17736kB present:14680064kB = managed:14326620kB mlocked:0kB bounce:0kB free_pcp:288kB local_pcp:28kB = free_cma:0kB >>>> [1584290.237051] lowmem_reserve[]: 0 0 0 0 >>>> [1584290.260423] Node 0 DMA: 1*4kB (U) 1*8kB (U) 0*16kB 0*32kB = 2*64kB (U) 1*128kB (U) 1*256kB (U) 0*512kB 1*1024kB (U) 0*2048kB = 3*4096kB (M) =3D 13836kB >>>> [1584290.308847] Node 0 DMA32: 12500*4kB (UMEH) 553*8kB (MH) 0*16kB = 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB =3D = 54424kB >>>> [1584290.358363] Node 0 Normal: 0*4kB 25*8kB (H) 0*16kB 5*32kB (H) = 1*64kB (H) 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB =3D 424kB >>>> [1584290.409087] 1465768 total pagecache pages >>>> [1584290.434531] 4165289 pages RAM >>>> [1584290.459616] 0 pages HighMem/MovableOnly >>>> [1584290.484480] 104766 pages reserved >>>> [1584290.508709] 0 pages hwpoisoned >>>> [1584301.710231] team0: Failed to send options change via netlink = (err -105) >>>> [1584302.635731] telegraf invoked oom-killer: = gfp_mask=3D0x400dc0(GFP_KERNEL_ACCOUNT|__GFP_ZERO), order=3D1, = oom_score_adj=3D0 >>>> [1584302.682874] CPU: 0 PID: 3494492 Comm: telegraf Tainted: G = O 5.11.4 #1 >>>> [1584302.729535] Hardware name: Supermicro = SYS-5038MR-H8TRF/X10SRD-F, BIOS 3.2 11/22/2019 >>>> [1584302.776532] Call Trace: >>>> [1584302.799361] dump_stack+0x58/0x6b >>>> [1584302.821791] dump_header+0x4c/0x2e6 >>>> [1584302.843580] oom_kill_process.cold+0xb/0x10 >>>> [1584302.865223] out_of_memory.part.0+0x125/0x5f0 >>>> [1584302.886641] out_of_memory+0x54/0xa0 >>>> [1584302.907302] __alloc_pages_slowpath.constprop.0+0xb03/0xfb0 >>>> [1584302.927913] __alloc_pages_nodemask+0x15a/0x180 >>>> [1584302.947874] __get_free_pages+0x8/0x30 >>>> [1584302.967246] pgd_alloc+0x21/0x180 >>>> [1584302.986355] mm_alloc+0x1af/0x250 >>>> [1584303.005085] alloc_bprm+0x80/0x2a0 >>>> [1584303.023328] do_execveat_common+0x8b/0x330 >>>> [1584303.041181] __x64_sys_execve+0x2b/0x40 >>>> [1584303.058513] do_syscall_64+0x2d/0x40 >>>> [1584303.075281] entry_SYSCALL_64_after_hwframe+0x44/0xa9 >>>> [1584303.091891] RIP: 0033:0x488376 >>>> [1584303.108045] Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc = cc cc cc cc cc 48 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 48 8b 44 24 = 08 0f 05 <48> 3d 01 f0 ff ff 76 1b 48 c7 44 24 28 ff ff ff ff 48 c7 44 = 24 30 >>>> [1584303.159632] RSP: 002b:000000c001108528 EFLAGS: 00000206 = ORIG_RAX: 000000000000003b >>>> [1584303.195446] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: = 0000000000488376 >>>> [1584303.231451] RDX: 000000c002b1a080 RSI: 000000c0028432e0 RDI: = 000000c000cae660 >>>> [1584303.267407] RBP: 000000c0011086c8 R08: 0000000000000018 R09: = 0000000000000000 >>>> [1584303.303594] R10: 0000000000000008 R11: 0000000000000206 R12: = 000000000047f258 >>>> [1584303.340218] R13: 000000000000000e R14: 000000000000000d R15: = 0000000000000100 >>>> [1584303.379094] Mem-Info: >>>> [1584303.398713] active_anon:8159 inactive_anon:2138194 = isolated_anon:0 >>>> active_file:12975 inactive_file:168 = isolated_file:32 >>>> unevictable:909709 dirty:12864 writeback:10 >>>> slab_reclaimable:42415 slab_unreclaimable:154783 >>>> mapped:39825 shmem:14744 pagetables:26041 bounce:0 >>>> free:537002 free_pcp:1813 free_cma:0 >>>> [1584303.547011] Node 0 active_anon:32636kB inactive_anon:8552776kB = active_file:51476kB inactive_file:1112kB unevictable:3638836kB = isolated(anon):0kB isolated(file):128kB mapped:159480kB dirty:51024kB = writeback:28kB shmem:58976kB writeback_tmp:0kB kernel_stack:5392kB = pagetables:104164kB all_unreclaimable? no >>>> [1584303.640025] Node 0 DMA free:13428kB min:12kB low:24kB = high:36kB reserved_highatomic:0KB active_anon:0kB inactive_anon:0kB = active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB = present:15968kB managed:15884kB mlocked:0kB bounce:0kB free_pcp:0kB = local_pcp:0kB free_cma:0kB >>>> [1584303.739414] lowmem_reserve[]: 0 1741 15726 15726 >>>> [1584303.764535] Node 0 DMA32 free:121320kB min:5872kB low:7652kB = high:9432kB reserved_highatomic:24576KB active_anon:5104kB = inactive_anon:761140kB active_file:37160kB inactive_file:772kB = unevictable:885428kB writepending:37672kB present:1965124kB = managed:1899588kB mlocked:0kB bounce:0kB free_pcp:1448kB local_pcp:0kB = free_cma:0kB >>>> [1584303.888935] lowmem_reserve[]: 0 0 13985 13985 >>>> [1584303.913532] Node 0 Normal free:1970692kB min:78608kB = low:92928kB high:107248kB reserved_highatomic:126976KB = active_anon:27524kB inactive_anon:7812248kB active_file:13664kB = inactive_file:1528kB unevictable:2753408kB writepending:12888kB = present:14680064kB managed:14326620kB mlocked:0kB bounce:0kB = free_pcp:4076kB local_pcp:0kB free_cma:0kB >>>> [1584304.036531] lowmem_reserve[]: 0 0 0 0 >>>> [1584304.060733] Node 0 DMA: 1*4kB (U) 40*8kB (U) 37*16kB (U) = 32*32kB (U) 24*64kB (U) 14*128kB (U) 8*256kB (U) 2*512kB (U) 1*1024kB = (U) 0*2048kB 1*4096kB (M) =3D 13460kB >>>> [1584304.134551] Node 0 DMA32: 15098*4kB (UMEH) 6204*8kB (UMEH) = 662*16kB (UMEH) 20*32kB (UMEH) 1*64kB (U) 0*128kB 0*256kB 0*512kB = 0*1024kB 0*2048kB 0*4096kB =3D 121320kB >>>> [1584304.209349] Node 0 Normal: 1038*4kB (UEH) 392*8kB (EH) 56*16kB = (UEH) 28*32kB (UEH) 14*64kB (MEH) 25*128kB (MEH) 6*256kB (MH) 3*512kB = (UMH) 3*1024kB (MH) 5*2048kB (UMH) 472*4096kB (U) =3D 1962872kB >>>> [1584304.287094] 933871 total pagecache pages >>>> [1584304.312815] 4165289 pages RAM >>>> [1584304.337915] 0 pages HighMem/MovableOnly >>>> [1584304.362522] 104766 pages reserved >>>> [1584304.386516] 0 pages hwpoisoned >>>>=20 >>>>> On 20 Mar 2021, at 11:55, Eric Dumazet = wrote: >>>>>=20 >>>>> On Sat, Mar 20, 2021 at 9:45 AM Martin Zaharinov = wrote: >>>>>>=20 >>>>>> Hi Wei >>>>>> Check this: >>>>>>=20 >>>>>> [ 39.706567] ------------[ cut here ]------------ >>>>>> [ 39.706568] RTNL: assertion failed at = net/ipv4/udp_tunnel_nic.c (557) >>>>>> [ 39.706585] WARNING: CPU: 0 PID: 429 at = net/ipv4/udp_tunnel_nic.c:557 __udp_tunnel_nic_reset_ntf+0xea/0x100 >>>>>=20 >>>>> Probably more relevant to Intel maintainers than Wei :/ >>>>>=20 >>>>>> [ 39.706594] Modules linked in: i40e(+) nf_nat_sip = nf_conntrack_sip nf_nat_pptp nf_conntrack_pptp nf_nat_tftp = nf_conntrack_tftp nf_nat_ftp nf_conntrack_ftp nf_nat nf_conntrack = nf_defrag_ipv6 nf_defrag_ipv4 acpi_ipmi ipmi_si ipmi_devintf = ipmi_msghandler rtc_cmos megaraid_sas >>>>>> [ 39.706614] CPU: 0 PID: 429 Comm: kworker/0:2 Tainted: G = O 5.11.7 #1 >>>>>> [ 39.706618] Hardware name: Supermicro X11DPi-N(T)/X11DPi-NT, = BIOS 3.4 11/23/2020 >>>>>> [ 39.706619] Workqueue: events work_for_cpu_fn >>>>>> [ 39.706627] RIP: 0010:__udp_tunnel_nic_reset_ntf+0xea/0x100 >>>>>> [ 39.706631] Code: c0 79 f1 00 00 0f 85 4e ff ff ff ba 2d 02 00 = 00 48 c7 c6 45 3c 3a 93 48 c7 c7 40 de 39 93 c6 05 a0 79 f1 00 01 e8 f5 = ad 0c 00 <0f> 0b e9 28 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f = 40 00 >>>>>> [ 39.706634] RSP: 0018:ffffa8390d9b3b38 EFLAGS: 00010292 >>>>>> [ 39.706637] RAX: 0000000000000039 RBX: ffff8e02630b2768 RCX: = 00000000ffdfffff >>>>>> [ 39.706639] RDX: 00000000ffdfffff RSI: ffff8e80ad400000 RDI: = 0000000000000001 >>>>>> [ 39.706641] RBP: ffff8e025df72000 R08: ffff8e80bb3fffe8 R09: = 00000000ffffffea >>>>>> [ 39.706643] R10: 00000000ffdfffff R11: 80000000ffe00000 R12: = ffff8e02630b2008 >>>>>> [ 39.706645] R13: 0000000000000000 R14: ffff8e024a88ba00 R15: = 0000000000000000 >>>>>> [ 39.706646] FS: 0000000000000000(0000) = GS:ffff8e40bf800000(0000) knlGS:0000000000000000 >>>>>> [ 39.706649] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >>>>>> [ 39.706651] CR2: 00000000004d8f40 CR3: 0000002ca140a002 CR4: = 00000000001706f0 >>>>>> [ 39.706652] DR0: 0000000000000000 DR1: 0000000000000000 DR2: = 0000000000000000 >>>>>> [ 39.706654] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: = 0000000000000400 >>>>>> [ 39.706656] Call Trace: >>>>>> [ 39.706658] i40e_setup_pf_switch+0x617/0xf80 [i40e] >>>>>> [ 39.706683] i40e_probe.part.0.cold+0x8dc/0x109e [i40e] >>>>>> [ 39.706708] ? acpi_ns_check_object_type+0xd4/0x193 >>>>>> [ 39.706713] ? acpi_ns_check_package_list+0xfd/0x205 >>>>>> [ 39.706716] ? __kmalloc+0x37/0x160 >>>>>> [ 39.706720] ? kmem_cache_alloc+0xcb/0x120 >>>>>> [ 39.706723] ? irq_get_irq_data+0x5/0x20 >>>>>> [ 39.706726] ? mp_check_pin_attr+0xe/0xf0 >>>>>> [ 39.706729] ? irq_get_irq_data+0x5/0x20 >>>>>> [ 39.706731] ? mp_map_pin_to_irq+0xb7/0x2c0 >>>>>> [ 39.706735] ? acpi_register_gsi_ioapic+0x86/0x150 >>>>>> [ 39.706739] ? pci_conf1_read+0x9f/0xf0 >>>>>> [ 39.706743] ? pci_bus_read_config_word+0x2e/0x40 >>>>>> [ 39.706746] local_pci_probe+0x1b/0x40 >>>>>> [ 39.706750] work_for_cpu_fn+0xb/0x20 >>>>>> [ 39.706754] process_one_work+0x1ec/0x350 >>>>>> [ 39.706758] worker_thread+0x24b/0x4d0 >>>>>> [ 39.706760] ? process_one_work+0x350/0x350 >>>>>> [ 39.706762] kthread+0xea/0x120 >>>>>> [ 39.706766] ? kthread_park+0x80/0x80 >>>>>> [ 39.706770] ret_from_fork+0x1f/0x30 >>>>>> [ 39.706774] ---[ end trace 7a203f3ec972a377 ]--- >>>>>>=20 >>>>>> Martin >>>>>>=20 >>>>>>=20 >>>>>>> On 17 Mar 2021, at 0:36, Wei Wang wrote: >>>>>>>=20 >>>>>>> Currently, napi_thread_wait() checks for NAPI_STATE_SCHED bit to >>>>>>> determine if the kthread owns this napi and could call = napi->poll() on >>>>>>> it. However, if socket busy poll is enabled, it is possible that = the >>>>>>> busy poll thread grabs this SCHED bit (after the previous = napi->poll() >>>>>>> invokes napi_complete_done() and clears SCHED bit) and tries to = poll >>>>>>> on the same napi. napi_disable() could grab the SCHED bit as = well. >>>>>>> This patch tries to fix this race by adding a new bit >>>>>>> NAPI_STATE_SCHED_THREADED in napi->state. This bit gets set in >>>>>>> ____napi_schedule() if the threaded mode is enabled, and gets = cleared >>>>>>> in napi_complete_done(), and we only poll the napi in kthread if = this >>>>>>> bit is set. This helps distinguish the ownership of the napi = between >>>>>>> kthread and other scenarios and fixes the race issue. >>>>>>>=20 >>>>>>> Fixes: 29863d41bb6e ("net: implement threaded-able napi poll = loop support") >>>>>>> Reported-by: Martin Zaharinov >>>>>>> Suggested-by: Jakub Kicinski >>>>>>> Signed-off-by: Wei Wang >>>>>>> Cc: Alexander Duyck >>>>>>> Cc: Eric Dumazet >>>>>>> Cc: Paolo Abeni >>>>>>> Cc: Hannes Frederic Sowa >>>>>>> --- >>>>>>> Change since v3: >>>>>>> - Add READ_ONCE() for thread->state and add comments in >>>>>>> ____napi_schedule(). >>>>>>>=20 >>>>>>> include/linux/netdevice.h | 2 ++ >>>>>>> net/core/dev.c | 19 ++++++++++++++++++- >>>>>>> 2 files changed, 20 insertions(+), 1 deletion(-) >>>>>>>=20 >>>>>>> diff --git a/include/linux/netdevice.h = b/include/linux/netdevice.h >>>>>>> index 5b67ea89d5f2..87a5d186faff 100644 >>>>>>> --- a/include/linux/netdevice.h >>>>>>> +++ b/include/linux/netdevice.h >>>>>>> @@ -360,6 +360,7 @@ enum { >>>>>>> NAPI_STATE_IN_BUSY_POLL, /* sk_busy_loop() owns this = NAPI */ >>>>>>> NAPI_STATE_PREFER_BUSY_POLL, /* prefer busy-polling over = softirq processing*/ >>>>>>> NAPI_STATE_THREADED, /* The poll is performed = inside its own thread*/ >>>>>>> + NAPI_STATE_SCHED_THREADED, /* Napi is currently = scheduled in threaded mode */ >>>>>>> }; >>>>>>>=20 >>>>>>> enum { >>>>>>> @@ -372,6 +373,7 @@ enum { >>>>>>> NAPIF_STATE_IN_BUSY_POLL =3D = BIT(NAPI_STATE_IN_BUSY_POLL), >>>>>>> NAPIF_STATE_PREFER_BUSY_POLL =3D = BIT(NAPI_STATE_PREFER_BUSY_POLL), >>>>>>> NAPIF_STATE_THREADED =3D BIT(NAPI_STATE_THREADED), >>>>>>> + NAPIF_STATE_SCHED_THREADED =3D = BIT(NAPI_STATE_SCHED_THREADED), >>>>>>> }; >>>>>>>=20 >>>>>>> enum gro_result { >>>>>>> diff --git a/net/core/dev.c b/net/core/dev.c >>>>>>> index 6c5967e80132..d3195a95f30e 100644 >>>>>>> --- a/net/core/dev.c >>>>>>> +++ b/net/core/dev.c >>>>>>> @@ -4294,6 +4294,13 @@ static inline void = ____napi_schedule(struct softnet_data *sd, >>>>>>> */ >>>>>>> thread =3D READ_ONCE(napi->thread); >>>>>>> if (thread) { >>>>>>> + /* Avoid doing set_bit() if the thread is = in >>>>>>> + * INTERRUPTIBLE state, cause = napi_thread_wait() >>>>>>> + * makes sure to proceed with napi polling >>>>>>> + * if the thread is explicitly woken from = here. >>>>>>> + */ >>>>>>> + if (READ_ONCE(thread->state) !=3D = TASK_INTERRUPTIBLE) >>>>>>> + set_bit(NAPI_STATE_SCHED_THREADED, = &napi->state); >>>>>>> wake_up_process(thread); >>>>>>> return; >>>>>>> } >>>>>>> @@ -6486,6 +6493,7 @@ bool napi_complete_done(struct napi_struct = *n, int work_done) >>>>>>> WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED)); >>>>>>>=20 >>>>>>> new =3D val & ~(NAPIF_STATE_MISSED | = NAPIF_STATE_SCHED | >>>>>>> + NAPIF_STATE_SCHED_THREADED | >>>>>>> NAPIF_STATE_PREFER_BUSY_POLL); >>>>>>>=20 >>>>>>> /* If STATE_MISSED was set, leave STATE_SCHED set, >>>>>>> @@ -6968,16 +6976,25 @@ static int napi_poll(struct napi_struct = *n, struct list_head *repoll) >>>>>>>=20 >>>>>>> static int napi_thread_wait(struct napi_struct *napi) >>>>>>> { >>>>>>> + bool woken =3D false; >>>>>>> + >>>>>>> set_current_state(TASK_INTERRUPTIBLE); >>>>>>>=20 >>>>>>> while (!kthread_should_stop() && !napi_disable_pending(napi)) = { >>>>>>> - if (test_bit(NAPI_STATE_SCHED, &napi->state)) { >>>>>>> + /* Testing SCHED_THREADED bit here to make sure = the current >>>>>>> + * kthread owns this napi and could poll on this = napi. >>>>>>> + * Testing SCHED bit is not enough because SCHED = bit might be >>>>>>> + * set by some other busy poll thread or by = napi_disable(). >>>>>>> + */ >>>>>>> + if (test_bit(NAPI_STATE_SCHED_THREADED, = &napi->state) || woken) { >>>>>>> WARN_ON(!list_empty(&napi->poll_list)); >>>>>>> __set_current_state(TASK_RUNNING); >>>>>>> return 0; >>>>>>> } >>>>>>>=20 >>>>>>> schedule(); >>>>>>> + /* woken being true indicates this thread owns = this napi. */ >>>>>>> + woken =3D true; >>>>>>> set_current_state(TASK_INTERRUPTIBLE); >>>>>>> } >>>>>>> __set_current_state(TASK_RUNNING); >>>>>>> -- >>>>>>> 2.31.0.rc2.261.g7f71774620-goog >>>>>>>=20 >>>>>>=20 >>>>=20 >>=20