From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx134.postini.com [74.125.245.134]) by kanga.kvack.org (Postfix) with SMTP id 52BDD6B005D for ; Sun, 9 Sep 2012 10:56:38 -0400 (EDT) Message-ID: <1347202600.5876.7.camel@sbsiddha-ivb> Subject: Re: mtd: kernel BUG at arch/x86/mm/pat.c:279! From: Suresh Siddha Reply-To: suresh.b.siddha@intel.com Date: Sun, 09 Sep 2012 07:56:40 -0700 In-Reply-To: References: <1340959739.2936.28.camel@lappy> <1347057778.26695.68.camel@sbsiddha-desk.sc.intel.com> <1347062045.26695.82.camel@sbsiddha-desk.sc.intel.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Linus Torvalds Cc: Sasha Levin , Andrew Morton , dwmw2@infradead.org, "linux-kernel@vger.kernel.org" , linux-mtd@lists.infradead.org, linux-mm , Dave Jones On Sat, 2012-09-08 at 12:57 -0700, Linus Torvalds wrote: > Whatever. Something like this (TOTALLY UNTESTED) attached patch should > get the mtdchar overflows to go away, It looks good to me. Acked-by: Suresh Siddha Sasha, can you please give this a try? > but it does *not* fix the fact > that the MTRR start/end model is broken. It really is technically > valid to have a resource_size_t range of 0xfffffffffffff000+0x1000, > and right now it causes a BUG_ON() in pat.c. > > Suresh? yes but that is not a valid range I think because of the supported physical address bit limits of the processor and also the max architecture limit of 52 address bits. I guess we should be checking for those limits in pat.c, especially bits above 52 are ignored by the HW and they can easily cause conflicting aliases with other valid regions. I will get back with a different patch to fix this. thanks, suresh -- 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