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 BFF47C388F9 for ; Mon, 2 Nov 2020 09:08:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7435822272 for ; Mon, 2 Nov 2020 09:08:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728005AbgKBJIF convert rfc822-to-8bit (ORCPT ); Mon, 2 Nov 2020 04:08:05 -0500 Received: from eu-smtp-delivery-151.mimecast.com ([207.82.80.151]:46547 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728217AbgKBJID (ORCPT ); Mon, 2 Nov 2020 04:08:03 -0500 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-2-3gt7SuvxPWOqa-ZpIA1B2g-1; Mon, 02 Nov 2020 09:06:39 +0000 X-MC-Unique: 3gt7SuvxPWOqa-ZpIA1B2g-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Mon, 2 Nov 2020 09:06:38 +0000 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Mon, 2 Nov 2020 09:06:38 +0000 From: David Laight To: 'Greg KH' CC: 'David Hildenbrand' , Al Viro , Nick Desaulniers , Christoph Hellwig , "kernel-team@android.com" , Andrew Morton , Jens Axboe , Arnd Bergmann , David Howells , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "linux-mips@vger.kernel.org" , "linux-parisc@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" , "linux-s390@vger.kernel.org" , "sparclinux@vger.kernel.org" , "linux-block@vger.kernel.org" , "linux-scsi@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "linux-aio@kvack.org" , "io-uring@vger.kernel.org" , "linux-arch@vger.kernel.org" , "linux-mm@kvack.org" , "netdev@vger.kernel.org" , "keyrings@vger.kernel.org" , "linux-security-module@vger.kernel.org" Subject: RE: Buggy commit tracked to: "Re: [PATCH 2/9] iov_iter: move rw_copy_check_uvector() into lib/iov_iter.c" Thread-Topic: Buggy commit tracked to: "Re: [PATCH 2/9] iov_iter: move rw_copy_check_uvector() into lib/iov_iter.c" Thread-Index: AQHWqE5GNDfnH4y9nkGWtfqJueR1KKmjTCJQgAAN4UiAAAD2IIAASOeCgAF+12CAAB+UKYAAAQNg///yIQCAD2i/YA== Date: Mon, 2 Nov 2020 09:06:38 +0000 Message-ID: <0ab5ac71f28d459db2f350c2e07b88ca@AcuMS.aculab.com> References: <5fd6003b-55a6-2c3c-9a28-8fd3a575ca78@redhat.com> <20201022104805.GA1503673@kroah.com> <20201022121849.GA1664412@kroah.com> <98d9df88-b7ef-fdfb-7d90-2fa7a9d7bab5@redhat.com> <20201022125759.GA1685526@kroah.com> <20201022135036.GA1787470@kroah.com> <134f162d711d466ebbd88906fae35b33@AcuMS.aculab.com> <935f7168-c2f5-dd14-7124-412b284693a2@redhat.com> <999e2926-9a75-72fd-007a-1de0af341292@redhat.com> <35d0ec90ef4f4a35a75b9df7d791f719@AcuMS.aculab.com> <20201023144718.GA2525489@kroah.com> In-Reply-To: <20201023144718.GA2525489@kroah.com> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org From: 'Greg KH' > Sent: 23 October 2020 15:47 > > On Fri, Oct 23, 2020 at 02:39:24PM +0000, David Laight wrote: > > From: David Hildenbrand > > > Sent: 23 October 2020 15:33 > > ... > > > I just checked against upstream code generated by clang 10 and it > > > properly discards the upper 32bit via a mov w23 w2. > > > > > > So at least clang 10 indeed properly assumes we could have garbage and > > > masks it off. > > > > > > Maybe the issue is somewhere else, unrelated to nr_pages ... or clang 11 > > > behaves differently. > > > > We'll need the disassembly from a failing kernel image. > > It isn't that big to hand annotate. > > I've worked around the merge at the moment in the android tree, but it > is still quite reproducable, and will try to get a .o file to > disassemble on Monday or so... Did this get properly resolved? David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)