Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764177AbXHLUdH (ORCPT ); Sun, 12 Aug 2007 16:33:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756057AbXHLUcw (ORCPT ); Sun, 12 Aug 2007 16:32:52 -0400 Received: from hancock.steeleye.com ([71.30.118.248]:45871 "EHLO hancock.sc.steeleye.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753662AbXHLUcv (ORCPT ); Sun, 12 Aug 2007 16:32:51 -0400 Subject: Re: [PATCH] Re: cciss: warning: right shift count >= width of type From: James Bottomley To: Al Viro Cc: Rene Herman , Jesper Juhl , linux-scsi@vger.kernel.org, Linux Kernel Mailing List , Mike.miller@hp.com In-Reply-To: <20070812065806.GC21089@ftp.linux.org.uk> References: <200708120228.26234.jesper.juhl@gmail.com> <46BE60B5.7010708@gmail.com> <20070812065806.GC21089@ftp.linux.org.uk> Content-Type: text/plain Date: Sun, 12 Aug 2007 15:32:49 -0500 Message-Id: <1186950769.3400.34.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.10.3 (2.10.3-2.fc7) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1840 Lines: 49 On Sun, 2007-08-12 at 07:58 +0100, Al Viro wrote: > On Sun, Aug 12, 2007 at 03:21:57AM +0200, Rene Herman wrote: > > @@ -2609,13 +2609,13 @@ static void do_cciss_request(request_queue_t *q) > > } else { > > c->Request.CDBLen = 16; > > c->Request.CDB[1]= 0; > > - c->Request.CDB[2]= (start_blk >> 56) & 0xff; //MSB > > - c->Request.CDB[3]= (start_blk >> 48) & 0xff; > > - c->Request.CDB[4]= (start_blk >> 40) & 0xff; > > - c->Request.CDB[5]= (start_blk >> 32) & 0xff; > > - c->Request.CDB[6]= (start_blk >> 24) & 0xff; > > - c->Request.CDB[7]= (start_blk >> 16) & 0xff; > > - c->Request.CDB[8]= (start_blk >> 8) & 0xff; > > + c->Request.CDB[2]= ((u64)start_blk >> 56) & 0xff; //MSB > > + c->Request.CDB[3]= ((u64)start_blk >> 48) & 0xff; > > + c->Request.CDB[4]= ((u64)start_blk >> 40) & 0xff; > > + c->Request.CDB[5]= ((u64)start_blk >> 32) & 0xff; > > + c->Request.CDB[6]= ((u64)start_blk >> 24) & 0xff; > > + c->Request.CDB[7]= ((u64)start_blk >> 16) & 0xff; > > + c->Request.CDB[8]= ((u64)start_blk >> 8) & 0xff; > > put_unaligned(cpu_to_be64(start_blk), &c->Request.CDB[2]); > > which is what's happening here anyway. Well ... this was debated a while ago ad nauseam: http://marc.info/?t=117699555300010 The main objection to what you propose is that it forces the u64 coercion even in the 32 bit start_blk case. The preferred solution as a result of that debate was simply to us a macro Andrew introduced: upper_32_bits() Which will silently replace zero in the non LBD case. I actually thought this had already been done. James James - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/