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=-0.6 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,T_DKIM_INVALID autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by aws-us-west-2-korg-lkml-1.web.codeaurora.org (Postfix) with ESMTP id F39ACC004E4 for ; Wed, 13 Jun 2018 08:27:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A9D0C208AF for ; Wed, 13 Jun 2018 08:27:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="SL5Xz/3p" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A9D0C208AF Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934711AbeFMI1K (ORCPT ); Wed, 13 Jun 2018 04:27:10 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:43194 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934124AbeFMI1I (ORCPT ); Wed, 13 Jun 2018 04:27:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=bLkhRzPct31wf7bKHFXNpTjmxuHtp1rXA3GeUf47UCU=; b=SL5Xz/3p4uERGI0ZCf+sgbl3P omhoyH/mHv0b6MS0dkI0D4Pg12P7znA7RV3FKGyixSCuJXCXawOkDS9qe7mS/MxCOMeTqDciUhFWv 7HrBV0TituMvrxMCIBezWiQYyO8ClJDRQ3AUq7E6Dg0nmGTG02MtW84OMH8CIFTcZryLigJ+lNb7V 7wSNTTBuficYvRdaZdvFKiC1Y4idBF+EJL0DuKtwLFHBEAKPKD1W/puaVmcM39wetkoSNVOEJ2N/e vTmZXK8v1Q6KXReqp21/QDQiQPUO/KJKy4cN7hapL3c59zOnMiVOe4Qa4vo1znDjnFV3ubVi13y5t 6HbRhQ6mA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1fT17O-0003cj-GT; Wed, 13 Jun 2018 08:27:02 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 40A62201EA7C8; Wed, 13 Jun 2018 10:27:00 +0200 (CEST) Date: Wed, 13 Jun 2018 10:27:00 +0200 From: Peter Zijlstra To: kernel test robot Cc: mingo@kernel.org, oleg@redhat.com, gkohli@codeaurora.org, tglx@linutronix.de, mpe@ellerman.id.au, bigeasy@linutronix.de, linux-kernel@vger.kernel.org, will.deacon@arm.com, dzickus@redhat.com, lkp@01.org Subject: Re: [lkp-robot] [watchdog/softlockup] 4808e7a5dc: BUG:KASAN:null-ptr-deref_in_h Message-ID: <20180613082700.GV12198@hirez.programming.kicks-ass.net> References: <20180612161832.428662402@infradead.org> <20180613050838.GK12146@yexl-desktop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180613050838.GK12146@yexl-desktop> User-Agent: Mutt/1.9.5 (2018-04-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 13, 2018 at 01:08:38PM +0800, kernel test robot wrote: > [ 0.037000] BUG: KASAN: null-ptr-deref in hrtimer_active+0x70/0xa0 > [ 0.037000] Read of size 4 at addr 0000000000000010 by task swapper/1 > [ 0.037000] > [ 0.037000] CPU: 0 PID: 1 Comm: swapper Tainted: G T 4.17.0-11348-g4808e7a #1 > [ 0.037000] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 > [ 0.037000] Call Trace: > [ 0.037000] ? kasan_report+0xe3/0x360 > [ 0.037000] ? hrtimer_active+0x70/0xa0 > [ 0.037000] ? hrtimer_try_to_cancel+0x17/0x210 > [ 0.037000] ? hrtimer_cancel+0x15/0x20 > [ 0.037000] ? softlockup_stop_fn+0x11/0x20 > [ 0.037000] ? lockup_detector_reconfigure+0x25/0xa0 > [ 0.037000] ? lockup_detector_init+0x51/0x5d > [ 0.037000] ? kernel_init_freeable+0xa9/0x243 > [ 0.037000] ? rest_init+0xd0/0xd0 > [ 0.037000] ? kernel_init+0xf/0x120 > [ 0.037000] ? rest_init+0xd0/0xd0 > [ 0.037000] ? ret_from_fork+0x24/0x30 ARGH, I thought I fixed that one.. I think that'll cure things, but let me do a KASAN build myself. --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -587,8 +587,8 @@ static __init void lockup_detector_setup return; mutex_lock(&watchdog_mutex); - softlockup_initialized = true; lockup_detector_reconfigure(); + softlockup_initialized = true; mutex_unlock(&watchdog_mutex); }