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=-0.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 BC601C433E0 for ; Thu, 11 Jun 2020 15:04:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A1396207ED for ; Thu, 11 Jun 2020 15:04:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728470AbgFKPEQ (ORCPT ); Thu, 11 Jun 2020 11:04:16 -0400 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:48131 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728419AbgFKPEP (ORCPT ); Thu, 11 Jun 2020 11:04:15 -0400 Received: from callcc.thunk.org (pool-100-0-195-244.bstnma.fios.verizon.net [100.0.195.244]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 05BF3eIm026407 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 11 Jun 2020 11:03:40 -0400 Received: by callcc.thunk.org (Postfix, from userid 15806) id 0903E4200DD; Thu, 11 Jun 2020 11:03:40 -0400 (EDT) Date: Thu, 11 Jun 2020 11:03:40 -0400 From: "Theodore Y. Ts'o" To: Christoph Hellwig Cc: Ritesh Harjani , linux-ext4@vger.kernel.org, jack@suse.com, Hillf Danton , linux-fsdevel@vger.kernel.org, Borislav Petkov , Marek Szyprowski , syzbot+82f324bb69744c5f6969@syzkaller.appspotmail.com Subject: Re: [PATCHv2 1/1] ext4: mballoc: Use this_cpu_read instead of this_cpu_ptr Message-ID: <20200611150340.GP1347934@mit.edu> References: <534f275016296996f54ecf65168bb3392b6f653d.1591699601.git.riteshh@linux.ibm.com> <20200610062538.GA24975@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200610062538.GA24975@infradead.org> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Tue, Jun 09, 2020 at 11:25:38PM -0700, Christoph Hellwig wrote: > On Tue, Jun 09, 2020 at 04:23:10PM +0530, Ritesh Harjani wrote: > > Simplify reading a seq variable by directly using this_cpu_read API > > instead of doing this_cpu_ptr and then dereferencing it. > > > > This also avoid the below kernel BUG: which happens when > > CONFIG_DEBUG_PREEMPT is enabled > > I see this warning all the time with ext4 using tests VMs, so lets get > this fixed ASAP before -rc1: > > Reviewed-by: Christoph Hellwig Thanks, applied. - Ted