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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 EA851C433DF for ; Sat, 4 Jul 2020 04:41:18 +0000 (UTC) Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9FE8F20737 for ; Sat, 4 Jul 2020 04:41:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9FE8F20737 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=vt.edu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernelnewbies-bounces+kernelnewbies=archiver.kernel.org@kernelnewbies.org Received: from localhost ([::1] helo=shelob.surriel.com) by shelob.surriel.com with esmtp (Exim 4.94) (envelope-from ) id 1jrZzI-0006UK-W8 for kernelnewbies@archiver.kernel.org; Sat, 04 Jul 2020 00:41:17 -0400 Received: from omr2.cc.ipv6.vt.edu ([2607:b400:92:8400:0:33:fb76:806e] helo=omr2.cc.vt.edu) by shelob.surriel.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1jrZxT-0004ys-Fa for Kernelnewbies@kernelnewbies.org; Sat, 04 Jul 2020 00:39:23 -0400 Received: from mr6.cc.vt.edu (mr6.cc.ipv6.vt.edu [IPv6:2607:b400:92:8500:0:af:2d00:4488]) by omr2.cc.vt.edu (8.14.4/8.14.4) with ESMTP id 0644dLZ4018057 for ; Sat, 4 Jul 2020 00:39:22 -0400 Received: from mail-qv1-f69.google.com (mail-qv1-f69.google.com [209.85.219.69]) by mr6.cc.vt.edu (8.14.7/8.14.7) with ESMTP id 0644dGte027444 for ; Sat, 4 Jul 2020 00:39:21 -0400 Received: by mail-qv1-f69.google.com with SMTP id cv20so10894277qvb.12 for ; Fri, 03 Jul 2020 21:39:21 -0700 (PDT) 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:cc:subject:in-reply-to:references :mime-version:content-transfer-encoding:date:message-id; bh=PfD6DhKTkRnQL6/KtoDMme4Lrm4gketAipSJuQnHWPU=; b=LuoeHtm/zw2fdZCQcnTz9lPB1AZo3wgibnDM669NlHklRabTqCsdndnSXhk2MrP3XK qOcKopC+ZV3DpyKQsXayLZ7LCP0XZtzH/4ehyD7I96UdDAbmMH45HT/FC5C0iEGArePy S1irA5jcOd7B21POOf4jFh7Zi85Tpqx6f5ZxIxYtfON35BAHYwFwCweBixv9U+nIjMzD QdOXRcvGAftKAYZ3koXxO2M8nTfLVdPasmdE/4KST6oWa40SVkTQ2FjIqfPYwLGbay64 vI0xmRwPzv0ZGbDVtaKDJZiVPGx3oCJ9XdhmBkupvb+2bGHuJ/bmNXU5S74IV1rcbnc5 uCzA== X-Gm-Message-State: AOAM533kH4nMm8yxjCIVk2d0ABoSVaRmp5kZ9X7yG8pluHXBgm0JwiV+ DTkdej2gvxpsQMKe5yNhyU4uVYvyIcvZKJn9GvshqhwAQgrh86e/Z57C8ibuqRme3ccQHoEiYsz rdzwK+i8rc+NvSy+DpM3aSpR5s7lBYjKibml5msA= X-Received: by 2002:aed:3b29:: with SMTP id p38mr40876933qte.350.1593837556555; Fri, 03 Jul 2020 21:39:16 -0700 (PDT) X-Google-Smtp-Source: ABdhPJybnlGvFdpqjeD2Q6fKGMzOZNZTUI9ITfVM5Ik+QS3x4wKaa7DwN2nMgKuzAWauABiN3tlaag== X-Received: by 2002:aed:3b29:: with SMTP id p38mr40876920qte.350.1593837556218; Fri, 03 Jul 2020 21:39:16 -0700 (PDT) Received: from turing-police ([2601:5c0:c001:c9e1::359]) by smtp.gmail.com with ESMTPSA id k45sm15187619qtc.62.2020.07.03.21.39.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Jul 2020 21:39:14 -0700 (PDT) From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Google-Original-From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Mailer: exmh version 2.9.0 11/07/2018 with nmh-1.7+dev To: "e- d8 i> sunshilong" Subject: Re: How can I investigate the cause of "watchdog: BUG: soft lockup"? In-Reply-To: References: Mime-Version: 1.0 Date: Sat, 04 Jul 2020 00:39:13 -0400 Message-ID: <36373.1593837553@turing-police> Cc: kernelnewbies X-BeenThere: kernelnewbies@kernelnewbies.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Learn about the Linux kernel List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1138077622791928732==" Errors-To: kernelnewbies-bounces+kernelnewbies=archiver.kernel.org@kernelnewbies.org --===============1138077622791928732== Content-Type: multipart/signed; boundary="==_Exmh_1593837553_13204P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit --==_Exmh_1593837553_13204P Content-Type: text/plain; charset=us-ascii > Could you please give me some hint on how to investigate the cause deeply? Shortening the call trace to the relevant lines: > Jul 3 10:23:31 yx kernel: [ 1176.166252] Call Trace: > Jul 3 10:23:31 yx kernel: [ 1176.166261] _raw_spin_lock+0x20/0x30 > Jul 3 10:23:31 yx kernel: [ 1176.166270] can_write+0x6c/0x2c0 [advcan] > Jul 3 10:23:31 yx kernel: [ 1176.166292] __vfs_write+0x3a/0x190 You get into function can_write() in module advcan. That tries to take a spinlock, while something else already has it. The spinlock call is (roughly) 15% of the way through the function can_write(). The 'modules linked in' list includes "advcan(OE)". The 'O' tells us it's an out-of-tree module, which means you need to talk to whoever wrote the module and find out why it's hanging on a spin lock (most likely something else is failing to release it). And that's about as far as we can hint, since we don't have the source for your out-of-tree module. If the people who wrote it would clean it up and get it into the base Linux tree, then we'd all have access to it and be able to help in much greater detail. --==_Exmh_1593837553_13204P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Comment: Exmh version 2.9.0 11/07/2018 iQIVAwUBXwAH8QdmEQWDXROgAQIB7w/8CGegCP7dvfxVGKKdlSyxByVpHuQHMzH8 XeziFszVJdYz03+UjRZ6Q/p2BPE/q8aT34lMXdZ4DHEG84QV8UqoBHK0srGlrj74 3jjPI3FMnY4+55imcOC763CYvnoloDK09dsUxMvUm0AZA9mbS42KSmjZyEo2Mdug G2x4j9P3mmzE+hoxCnWLImhGpBPEJhNZ/O5wLHNNgwfznQ+qj8N8Ryg361yWUF4d fBlNw9E3Uin/zZx1tD0GAcWtgOh5Q6HSW0KGIeYLcRfr+s9uacvPoc996Kj2SFMh sBFbXVkAhBdT//t9qOBvUsZ4PhCGGcOErXvsKOMEXrYSEPxfFj7R9QiJsdZqOIAb NjBZL3b72vjxYsds3X4nIIdYJjhCbvTPMGppYLNnZCEyoid77jkoMEE2Nk5ODUFD 9S9/CE3T72H6ZWxkas+xbb2SR1bbeTwyXoZ1ModJ+ztvzJhwMYVU+9+2DwGTibyz hlP2h0JDEs1KbGL0KwuGJapCwI36Fv6BJ5zSua333swf7CmY6L1sXJRGD+cD6Pjh gQeY1YPt7tkKiSKj3nICAilRA0gIjhatiEmBVott4E9SeQLkS4+F6VdfcjYcWemb j58kN/egA5MxtEhBiPpaqk12ruOWLDGd62mR11of4lrcSBhNCqRq3qqUfj70mB55 83OXecyZ/fU= =olW2 -----END PGP SIGNATURE----- --==_Exmh_1593837553_13204P-- --===============1138077622791928732== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies --===============1138077622791928732==--