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=-3.8 required=3.0 tests=BAYES_00, 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 22B36C433ED for ; Mon, 26 Apr 2021 20:26:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E6A2B6105A for ; Mon, 26 Apr 2021 20:26:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241728AbhDZU1d (ORCPT ); Mon, 26 Apr 2021 16:27:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42324 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238875AbhDZU1d (ORCPT ); Mon, 26 Apr 2021 16:27:33 -0400 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 28AACC061574 for ; Mon, 26 Apr 2021 13:26:51 -0700 (PDT) Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94) (envelope-from ) id 1lb7oe-000NkK-0C; Mon, 26 Apr 2021 22:26:48 +0200 Message-ID: Subject: Re: [BISECTED] 5.12 hangs at reboot From: Johannes Berg To: Harald Arnesen , Linus Torvalds Cc: Linux Kernel Mailing List Date: Mon, 26 Apr 2021 22:26:47 +0200 In-Reply-To: <28e21004-13ff-9d5f-0c5d-4c1e79cf628a@skogtun.org> References: <09464e67-f3de-ac09-28a3-e27b7914ee7d@skogtun.org> <28e21004-13ff-9d5f-0c5d-4c1e79cf628a@skogtun.org> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.4 (3.38.4-1.fc33) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-malware-bazaar: not-scanned Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2021-04-26 at 22:10 +0200, Harald Arnesen wrote: > Linus Torvalds [26.04.2021 20:59]: > > > There's a lockdep assertion there, but you don't seem to have lockdep > > enabled. So it be interesting to see what happens if you > > > >  (a) enable lockdep > > At the risk of sounding stupid: where is this config option? CONFIG_PROVE_LOCKING I have no idea *where* it is either (in menuconfig or so), so if you're in menuconfig, just hit / and enter PROVE_LOCKING. It'll come up with a list of entries (probably only one) labeled (1), (2), ... Hit the number key with the right number and menuconfig will take you there. If you can't enable it, then you need DEBUG_KERNEL first. But if you can e.g. switch to a VT (ctrl-alt-fn) and get a stackdump shown on the screen while it hangs while shutting down (need to wait 2-3 minutes I guess), that's probably enough. johannes