Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756722AbcLBTwU (ORCPT ); Fri, 2 Dec 2016 14:52:20 -0500 Received: from mail-oi0-f52.google.com ([209.85.218.52]:36778 "EHLO mail-oi0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750919AbcLBTwT (ORCPT ); Fri, 2 Dec 2016 14:52:19 -0500 MIME-Version: 1.0 In-Reply-To: <1480706527-21274-1-git-send-email-fabf@skynet.be> References: <1480706527-21274-1-git-send-email-fabf@skynet.be> From: Dan Williams Date: Fri, 2 Dec 2016 11:52:18 -0800 Message-ID: Subject: Re: [PATCH 7/8 linux-next] mm: warn about possible alignment problem To: Fabian Frederick Cc: "linux-nvdimm@lists.01.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1726 Lines: 47 On Fri, Dec 2, 2016 at 11:22 AM, Fabian Frederick wrote: > Commit 5f29a77cd957 > ("mm: fix mixed zone detection in devm_memremap_pages") > Aligned resource limits before region_intersects() which breaks > the following with false assertions on kernel command line: memmap=4M!700M > > "devm_memremap_pages attempted on mixed region [ mem 0x2bc00000-0x2bfffff > flags 0x200]" > > Memory regions > 0x100000-0x2bbfffff: usable > 0x2bc000000-0x2bbfffff: persistent > 0x2c0000000-0x2bffffff: usable > > resource start: 0x2bc00000 > align start: 0x28000000 > resource size: 0x3fffffff > align size: 0x80000000 > SECTION_SIZE: 0x8000000 > > Now we need aligned memmap declarations based on 128M in this case > eg memmap=128!640M > > Signed-off-by: Fabian Frederick > --- > kernel/memremap.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/memremap.c b/kernel/memremap.c > index b501e39..1bb5eec 100644 > --- a/kernel/memremap.c > +++ b/kernel/memremap.c > @@ -296,8 +296,8 @@ void *devm_memremap_pages(struct device *dev, struct resource *res, > IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE); > > if (is_ram == REGION_MIXED) { > - WARN_ONCE(1, "%s attempted on mixed region %pr\n", > - __func__, res); > + WARN_ONCE(1, "%s attempted on mixed region %pr or arguments not aligned to section size: %#lx\n", > + __func__, res, SECTION_SIZE); > return ERR_PTR(-ENXIO); > } This should be addressed by the sub-section hotplug patches: "[PATCH 00/11] mm: sub-section memory hotplug support" https://lkml.org/lkml/2016/12/1/740