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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E425EC77B7E for ; Thu, 1 Jun 2023 10:29:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232683AbjFAK3p convert rfc822-to-8bit (ORCPT ); Thu, 1 Jun 2023 06:29:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34592 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232812AbjFAK30 (ORCPT ); Thu, 1 Jun 2023 06:29:26 -0400 Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [185.58.85.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EF202170A for ; Thu, 1 Jun 2023 03:28:51 -0700 (PDT) Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) by relay.mimecast.com with ESMTP with both STARTTLS and AUTH (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id uk-mta-318-0fhv99D0OlqPvimtjd92WA-1; Thu, 01 Jun 2023 11:28:49 +0100 X-MC-Unique: 0fhv99D0OlqPvimtjd92WA-1 Received: from AcuMS.Aculab.com (10.202.163.4) by AcuMS.aculab.com (10.202.163.4) with Microsoft SMTP Server (TLS) id 15.0.1497.48; Thu, 1 Jun 2023 11:28:45 +0100 Received: from AcuMS.Aculab.com ([::1]) by AcuMS.aculab.com ([::1]) with mapi id 15.00.1497.048; Thu, 1 Jun 2023 11:28:45 +0100 From: David Laight To: 'Christoph Hellwig' , Daniel Gomez CC: Keith Busch , Jens Axboe , "Sagi Grimberg" , Pankaj Raghav , "mcgrof@kernel.org" , "linux-nvme@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: RE: [PATCH] nvme: Increase block size variable size to 32-bit Thread-Topic: [PATCH] nvme: Increase block size variable size to 32-bit Thread-Index: AQHZk8CokMhanTXaB0ibg7NXJWn+ba91vvfg Date: Thu, 1 Jun 2023 10:28:45 +0000 Message-ID: References: <20230530154231.8313-1-da.gomez@samsung.com> <20230531130325.GE27468@lst.de> In-Reply-To: <20230531130325.GE27468@lst.de> 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 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: linux-kernel@vger.kernel.org From: Christoph Hellwig > Sent: 31 May 2023 14:03 > > > + u32 bs = 1 << ns->lba_shift; > > Make that 1 a 1U so that we're not going to run into sign extension > issues when using up all bits in the u32 :) Not 'sign extension' but obscure integer shift/conversion issues that really only affect 1's compliment and sign-overpunch cpu. I'm not even sure gcc/clang support any non 2's compliment systems. > Otherwise looks good: Probably improves the generated code as well. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)