Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752295AbbBRJ6I (ORCPT ); Wed, 18 Feb 2015 04:58:08 -0500 Received: from mail-wg0-f43.google.com ([74.125.82.43]:55793 "EHLO mail-wg0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751035AbbBRJ6F (ORCPT ); Wed, 18 Feb 2015 04:58:05 -0500 Message-ID: <54E46228.9060308@plexistor.com> Date: Wed, 18 Feb 2015 11:58:00 +0200 From: Boaz Harrosh User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: Ross Zwisler CC: Ingo Molnar , x86@kernel.org, linux-kernel , "Roger C. Pao" , Dan Williams , Thomas Gleixner , Linus Torvalds , linux-nvdimm , "H. Peter Anvin" Subject: Re: [PATCH 3/3] pmem: Allow request_mem to fail, (CONFIG_BLK_DEV_PMEM_IGNORE_REQUEST_MEM_RET) References: <54E1CF5B.9020905@plexistor.com> <54E1D36B.4000905@plexistor.com> <1424206333.12687.8.camel@theros.lm.intel.com> In-Reply-To: <1424206333.12687.8.camel@theros.lm.intel.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1512 Lines: 47 On 02/17/2015 10:52 PM, Ross Zwisler wrote: > On Mon, 2015-02-16 at 13:24 +0200, Boaz Harrosh wrote: >> With old Kernels there was a bug in x86 where any unknown >> memory chip type would come up BUSY when calling >> request_mem_region_exclusive(). >> >> So for pmem to work with old Kernels and real NvDIMM chips >> we have a new Kconfig option CONFIG_BLK_DEV_PMEM_IGNORE_REQUEST_MEM_RET. >> >> People have been running with hacked up pmem that will ignore >> the return code from request_mem_region_exclusive. So here it is >> official >> >> Signed-off-by: Boaz Harrosh > Hi Ross, good morning > I'm confused - I thought that this behavior was fixed by patch 1/3? > With that patch this memory reservation should not fail, correct? > Yes, I have tested it extensively and PATCH-1/3 fixes this problem for sure. > If so, why do we need this patch? > I put in this patch for people that do-not-want/cannot compile their own Kernel but have a need for pmem.c regardless. I will not include this patch in the final submitted Kernel. Given that patch-1 gets accepted before the merge of pmem. Lets say that patch-1 and patch-3 are either or. A tree that has 1/3 does not need 3/3, a tree that does not have 1/3 needs 3/3. <> Thanks Boaz -- 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/