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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY 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 41866C4708F for ; Wed, 2 Jun 2021 15:18:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2DEF760698 for ; Wed, 2 Jun 2021 15:18:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231837AbhFBPUW (ORCPT ); Wed, 2 Jun 2021 11:20:22 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:58556 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232101AbhFBPUK (ORCPT ); Wed, 2 Jun 2021 11:20:10 -0400 Received: from imap.suse.de (imap-alt.suse-dmz.suse.de [192.168.254.47]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id E817122BD5; Wed, 2 Jun 2021 15:18:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1622647106; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EExQFawgGd7iNB9vNu/Slav2uxSKgTIBcsMBzXZv3GA=; b=WkSOT0SOldZpcTtjEBQH6MupD+n2D9MSEW02p2DCkoaSx8AMDtvclb+QEWL0ot2okh27dT I+DrC27OP2RI5wshebG4wLe2ypqk5obXoBoEol3nJk3rAKVE2OTD5KkktPB/Jqb/T0fcj5 HrXbzcM/0t+8wpJrHLSVKsEuzQNOWFM= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1622647106; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EExQFawgGd7iNB9vNu/Slav2uxSKgTIBcsMBzXZv3GA=; b=yzQYKBDyRizkQtDd2NGfB/KbTYIyk4CHeQcNd1TjIV886EPeXAZFxIruQUPpYd3VqpLNIN rxeW9ohAz/lECHAA== Received: by imap.suse.de (Postfix, from userid 51) id E0B3E11CD5; Wed, 2 Jun 2021 16:04:03 +0000 (UTC) Received: from imap3-int (imap-alt.suse-dmz.suse.de [192.168.254.47]) by imap.suse.de (Postfix) with ESMTP id CAE9411EE1; Wed, 2 Jun 2021 14:22:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1622643764; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EExQFawgGd7iNB9vNu/Slav2uxSKgTIBcsMBzXZv3GA=; b=sKT6om9kRHiNpIUHSatr7Fbve41lPc/J6+joteUqMdMyUwawbCXLYogM4ZeqXfu9/uhqu8 kb6+k4KBhBpuyfa07QA7f/QNlxrK0nHEDHXH03BNU3z55/OB6ZSc3yOj+AwSjyDXN/YLPh tCSe8nHx5NNQTX6xvXcgDJkuf9aNIyM= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1622643764; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EExQFawgGd7iNB9vNu/Slav2uxSKgTIBcsMBzXZv3GA=; b=5ImJD4SUYB2b4tkRVwSm/D7kHCRbSua36lpV7taCsaWdf/53TI5frd/Z3l+Nfn6mC57Bj5 mLysOBBDxaJnKwCA== Received: from director2.suse.de ([192.168.254.72]) by imap3-int with ESMTPSA id tAMPLjOUt2BcZgAALh3uQQ (envelope-from ); Wed, 02 Jun 2021 14:22:43 +0000 Received: from localhost (brahms [local]) by brahms (OpenSMTPD) with ESMTPA id 5284bd4d; Wed, 2 Jun 2021 14:22:43 +0000 (UTC) Date: Wed, 2 Jun 2021 15:22:42 +0100 From: Luis Henriques To: Peter Oberparleiter Cc: linux-kernel@vger.kernel.org Subject: Re: gcov: NULL pointer dereference with gcc 9.3.1 Message-ID: References: <0a013450-75eb-de2c-f90a-3df193800cea@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <0a013450-75eb-de2c-f90a-3df193800cea@linux.ibm.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 02, 2021 at 02:35:31PM +0200, Peter Oberparleiter wrote: > On 01.06.2021 17:56, Luis Henriques wrote: > > Hi! > > > > Maybe this is a known (gcc?) issue, but I'm seeing a NULL pointer splat if > > I instrument my kernel (or a module, more specifically) using gcc 9.3.1. > > > > It looks like, during initialization in __gcov_init(), gcov_info struct is > > invalid: the filename seems to be correct but ->function is NULL and > > ->n_functions contains garbage. > > Thanks for reporting this issue. The symptoms you're seeing look similar > to those that occur when the struct gcov_info layout emitted by GCC does > not match the one used by the kernel. In particular a change in the > GCOV_COUNTER value can cause this behavior. > > I've checked upstream GCC 9.3.1 and it seems to match what is used by > the kernel for that GCC version. Could you provide the exact version of > the compiler you are using? Both 'gcc --version' output and the GCC > package version should help. Also what architecture are you seeing this on? Here's the output of 'gcc --version': gcc (SUSE Linux) 9.3.1 20200903 [revision 9790fa53b48f3a48e0f7a7ad65e2bbf3b206a7b0] Copyright (C) 2019 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. This is the version shipped with openSUSE Tumbleweed, and I'm using it to compile an x86_64 kernel. Regarding the 'package version', I'm assuming the packages as per the distro package version, right? Here's the data from 'zypper info': Information for package gcc9: ----------------------------- Repository : Main Repository (OSS) Name : gcc9 Version : 9.3.1+git1684-3.5 Arch : x86_64 Vendor : openSUSE Installed Size : 94.6 MiB Installed : Yes (automatically) Status : up-to-date Source package : gcc9-9.3.1+git1684-3.5.src Do you have a link with binaries I could test for upstream 9.3.1? I checked [1] but there's only 9.3.0. [1] https://mirrors.edge.kernel.org/pub/tools/crosstool/files/bin/x86_64/ Cheers, -- Luís