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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 CEEA1C2BA19 for ; Wed, 15 Apr 2020 19:17:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A5235206D5 for ; Wed, 15 Apr 2020 19:17:10 +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="gGS2zUUa" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2440357AbgDOTRB (ORCPT ); Wed, 15 Apr 2020 15:17:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S2437909AbgDOTQx (ORCPT ); Wed, 15 Apr 2020 15:16:53 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7BF48C061A0C; Wed, 15 Apr 2020 12:16:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To: Subject:Sender:Reply-To:Content-ID:Content-Description; bh=XpaPanv1P8dxEy8FWJJXMKpNO3YbUQ5peJRz4Dbpbbc=; b=gGS2zUUaAdPJoqNmMnnZpkxb+X I9saZqG+BFe4uyf5jhZSM8T2w3EnlsbJ3GsmHI7HB2SnFNoF8Bo6rr1ZI/nmitRPBDcaqG3UPUmrs yRGIaQxS9ZO08/AQUIJ6gKkITOnVM+9igfKuHn8Igyq4fqTQtY4XpmobWOLmdP2+LhYwZM57yZDu7 4vET80BOlTyFSU1f61QE0LdtAb5GXW4Vcz1hvcBUG+W2UV+oVON0S+wZ/haFuokER+rmafEIzyTzH /TRBTuIkIeiCVMOqoB9Qzkk9oErSbZP6rQKyHvobv/S/zdzgjwPS7k3DmU/LTOXAaPieKd7xHCmOa KAmQiAKA==; Received: from [2601:1c0:6280:3f0::19c2] by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jOnWl-0000Eo-4n; Wed, 15 Apr 2020 19:16:51 +0000 Subject: Re: linux-next: Tree for Apr 10 (lib/test_printf.ko) To: Steven Rostedt , Brendan Higgins Cc: Naresh Kamboju , Linus Torvalds , Greg Kroah-Hartman , "Rafael J. Wysocki" , Stephen Rothwell , Linux Next Mailing List , Linux Kernel Mailing List , Rasmus Villemoes , Heikki Krogerus References: <20200410132706.170811b7@canb.auug.org.au> <27c212c4-b522-561d-411c-e74dc0ff0b74@infradead.org> <2b0f5d2e-3fe5-10c9-2a9a-9a0b341a52d5@infradead.org> <20200415185545.GA1632@home.goodmis.org> From: Randy Dunlap Message-ID: <26e0f0dd-4ea2-14e7-fae5-81a5a1451272@infradead.org> Date: Wed, 15 Apr 2020 12:16:49 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200415185545.GA1632@home.goodmis.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-next-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-next@vger.kernel.org On 4/15/20 11:55 AM, Steven Rostedt wrote: > On Tue, Apr 14, 2020 at 12:26:29PM -0700, Brendan Higgins wrote: >> On Sat, Apr 11, 2020 at 11:22 PM Randy Dunlap wrote: >>> >>> On 4/11/20 10:36 PM, Naresh Kamboju wrote: >>>> FYI, >>>> >>>> Is this problem related to, >>>> >>>> Regression reported on Linux next 5.6.0-rc4-next-20200305 on x86_64, >>>> i386, arm and arm64. The steps to reproduce is running kselftests lib >>>> printf.sh test case. >>>> Which is doing modprobe operations. >>>> >>>> BUG: kernel NULL pointer dereference, address: 00 - ida_free+0x76/0x140 >>>> >>>> https://lore.kernel.org/linux-kselftest/CAFd5g46Bwd8HS9-xjHLh_rB59Nfw8iAnM6aFe0QPcveewDUT6g@mail.gmail.com/T/ >>>> >>> >>> Looks similar. Lots of fwnode, software_node, ida stuff there. >> >> Sorry for the late reply, I was out. >> >> Yeah, I am pretty sure it is the same. Heikki proposed a fix that I am >> going to try. > > My test suite just tripped over this bug. Is this the patch that you think > fixes it? > > https://lore.kernel.org/linux-kselftest/20200414081513.GD2828150@kuha.fi.intel.com Yes, it is, but GregKH and Rafael Wysocki don't seem to like that patch and are suggesting some changes in lib/kobject.c (only pseudocode, no patch yet). > I'll add it to see if I can continue my testing. See the thread [PATCH v1] kobject: make sure parent is not released before children Here is Rafael's suggestion: https://lore.kernel.org/linux-kselftest/CAJZ5v0hNemTDVa_S-FfVMbrKjM-RWYoHh88asnUvTNxZinY2cw@mail.gmail.com/ -- ~Randy