From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 9 Jan 2001 12:58:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 9 Jan 2001 12:58:45 -0500 Received: from deimos.hpl.hp.com ([192.6.19.190]:60387 "EHLO deimos.hpl.hp.com") by vger.kernel.org with ESMTP id ; Tue, 9 Jan 2001 12:58:38 -0500 Date: Tue, 9 Jan 2001 09:58:35 -0800 To: Alan Cox Cc: jt@hpl.hp.com, John Ruttenberg , Linux kernel mailing list Subject: Re: wavelan has fatal error with 2.4.0 (but worked in 2.4.0-test12) Message-ID: <20010109095835.C30225@bougret.hpl.hp.com> Reply-To: jt@hpl.hp.com In-Reply-To: <20010109094217.A30225@bougret.hpl.hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: ; from alan@lxorguk.ukuu.org.uk on Tue, Jan 09, 2001 at 05:48:47PM +0000 Organisation: HP Labs Palo Alto Address: HP Labs, 1U-17, 1501 Page Mill road, Palo Alto, CA 94304, USA. E-mail: jt@hpl.hp.com From: Jean Tourrilhes Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 09, 2001 at 05:48:47PM +0000, Alan Cox wrote: > > > It is a bug in the driver. > > > > Please check again the code and point me the invalid > > udelay(). You will realise that there is no delay in the driver that > > is longer than 100ms. > > The udelay limit is set a lot lower than 100mS. It has to be somewhat lower > otherwise you have to do two levels of loops which will throw small udelay > timings a fair whack. Sorry, I mixed up my units. All the delays are lower than 100us. > > The bug is that udelay() can't be passed a variable but only a > > constant. Therefore bug in udelay(). > > Sounds like a compiler bug. > > #define udelay(n) (__builtin_constant_p(n) ? \ > ((n) > 20000 ? __bad_udelay() : __const_udelay((n) * 0x10c6ul)) : \ > __udelay(n)) > > non constants are covered. Therefore, compiler bug. Ouch ! Jean - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/