From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from terminus.zytor.com ([2001:1868:205::10] helo=mail.zytor.com) by bombadil.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TAkof-0007uY-Uy for linux-mtd@lists.infradead.org; Sun, 09 Sep 2012 16:57:02 +0000 Message-ID: <504CCA31.2000003@zytor.com> Date: Sun, 09 Sep 2012 09:56:17 -0700 From: "H. Peter Anvin" MIME-Version: 1.0 To: Linus Torvalds Subject: Re: mtd: kernel BUG at arch/x86/mm/pat.c:279! References: <1340959739.2936.28.camel@lappy> <1347057778.26695.68.camel@sbsiddha-desk.sc.intel.com> <1347062045.26695.82.camel@sbsiddha-desk.sc.intel.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Suresh Siddha , "linux-kernel@vger.kernel.org" , linux-mm , linux-mtd@lists.infradead.org, Sasha Levin , Dave Jones , Andrew Morton , dwmw2@infradead.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 09/08/2012 12:57 PM, Linus Torvalds wrote: > > Ack. > > Anyway, that means that the BUG_ON() is likely bogus, but so is the > whole calling convention. > > The 4kB range starting at 0xfffffffffffff000 sounds like a *valid* > range, but that requires that we fix the calling convention to not > have that "end" (exclusive) thing. It should either be "end" > (inclusive), or just "len". > On x86, it is definitely NOT a valid range. There is no physical addresses there, and there will never be any. > So it should either be start=0xfffffffffffff000 end=0xffffffffffffffff > or it should be start=0xfffffffffffff000 len=0x1000. I would strongly object to the former; that kind of inclusive ranges breed a whole class of bugs by themselves. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx160.postini.com [74.125.245.160]) by kanga.kvack.org (Postfix) with SMTP id 3B5746B005D for ; Sun, 9 Sep 2012 12:56:38 -0400 (EDT) Message-ID: <504CCA31.2000003@zytor.com> Date: Sun, 09 Sep 2012 09:56:17 -0700 From: "H. Peter Anvin" MIME-Version: 1.0 Subject: Re: mtd: kernel BUG at arch/x86/mm/pat.c:279! References: <1340959739.2936.28.camel@lappy> <1347057778.26695.68.camel@sbsiddha-desk.sc.intel.com> <1347062045.26695.82.camel@sbsiddha-desk.sc.intel.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Linus Torvalds Cc: Suresh Siddha , Sasha Levin , Andrew Morton , dwmw2@infradead.org, "linux-kernel@vger.kernel.org" , linux-mtd@lists.infradead.org, linux-mm , Dave Jones On 09/08/2012 12:57 PM, Linus Torvalds wrote: > > Ack. > > Anyway, that means that the BUG_ON() is likely bogus, but so is the > whole calling convention. > > The 4kB range starting at 0xfffffffffffff000 sounds like a *valid* > range, but that requires that we fix the calling convention to not > have that "end" (exclusive) thing. It should either be "end" > (inclusive), or just "len". > On x86, it is definitely NOT a valid range. There is no physical addresses there, and there will never be any. > So it should either be start=0xfffffffffffff000 end=0xffffffffffffffff > or it should be start=0xfffffffffffff000 len=0x1000. I would strongly object to the former; that kind of inclusive ranges breed a whole class of bugs by themselves. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754460Ab2IIQ5H (ORCPT ); Sun, 9 Sep 2012 12:57:07 -0400 Received: from terminus.zytor.com ([198.137.202.10]:49033 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751075Ab2IIQ5F (ORCPT ); Sun, 9 Sep 2012 12:57:05 -0400 Message-ID: <504CCA31.2000003@zytor.com> Date: Sun, 09 Sep 2012 09:56:17 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120828 Thunderbird/15.0 MIME-Version: 1.0 To: Linus Torvalds CC: Suresh Siddha , Sasha Levin , Andrew Morton , dwmw2@infradead.org, "linux-kernel@vger.kernel.org" , linux-mtd@lists.infradead.org, linux-mm , Dave Jones Subject: Re: mtd: kernel BUG at arch/x86/mm/pat.c:279! References: <1340959739.2936.28.camel@lappy> <1347057778.26695.68.camel@sbsiddha-desk.sc.intel.com> <1347062045.26695.82.camel@sbsiddha-desk.sc.intel.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/08/2012 12:57 PM, Linus Torvalds wrote: > > Ack. > > Anyway, that means that the BUG_ON() is likely bogus, but so is the > whole calling convention. > > The 4kB range starting at 0xfffffffffffff000 sounds like a *valid* > range, but that requires that we fix the calling convention to not > have that "end" (exclusive) thing. It should either be "end" > (inclusive), or just "len". > On x86, it is definitely NOT a valid range. There is no physical addresses there, and there will never be any. > So it should either be start=0xfffffffffffff000 end=0xffffffffffffffff > or it should be start=0xfffffffffffff000 len=0x1000. I would strongly object to the former; that kind of inclusive ranges breed a whole class of bugs by themselves. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.