From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752361AbeEQRVd (ORCPT ); Thu, 17 May 2018 13:21:33 -0400 Received: from mx2.suse.de ([195.135.220.15]:58130 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752320AbeEQRVc (ORCPT ); Thu, 17 May 2018 13:21:32 -0400 Date: Thu, 17 May 2018 19:21:28 +0200 From: Michal Hocko To: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= Cc: Joonsoo Kim , "Aneesh Kumar K . V" , Tony Lindgren , Vlastimil Babka , Johannes Weiner , Laura Abbott , Marek Szyprowski , Mel Gorman , Michal Nazarewicz , Minchan Kim , Rik van Riel , Russell King , Will Deacon , Andrew Morton , Linus Torvalds , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] Revert "mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE" Message-ID: <20180517172128.GX12670@dhcp22.suse.cz> References: <20180517125959.8095-1-ville.syrjala@linux.intel.com> <20180517132109.GU12670@dhcp22.suse.cz> <20180517133629.GH23723@intel.com> <20180517135832.GI23723@intel.com> <20180517164947.GV12670@dhcp22.suse.cz> <20180517171335.GN23723@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20180517171335.GN23723@intel.com> User-Agent: Mutt/1.9.5 (2018-04-13) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 17-05-18 20:13:35, Ville Syrjälä wrote: > On Thu, May 17, 2018 at 06:49:47PM +0200, Michal Hocko wrote: > > On Thu 17-05-18 16:58:32, Ville Syrjälä wrote: > > > On Thu, May 17, 2018 at 04:36:29PM +0300, Ville Syrjälä wrote: > > > > On Thu, May 17, 2018 at 03:21:09PM +0200, Michal Hocko wrote: > > > > > On Thu 17-05-18 15:59:59, Ville Syrjala wrote: > > > > > > From: Ville Syrjälä > > > > > > > > > > > > This reverts commit bad8c6c0b1144694ecb0bc5629ede9b8b578b86e. > > > > > > > > > > > > Make x86 with HIGHMEM=y and CMA=y boot again. > > > > > > > > > > Is there any bug report with some more details? It is much more > > > > > preferable to fix the issue rather than to revert the whole thing > > > > > right away. > > > > > > > > The machine I have in front of me right now didn't give me anything. > > > > Black screen, and netconsole was silent. No serial port on this > > > > machine unfortunately. > > > > > > Booted on another machine with serial: > > > > Could you provide your .config please? > > Attached. Not sure there's anything particularly useful in it though > since I've now seen this on all the highmem systems I've booted. It has CONFIG_HAVE_MEMBLOCK_NODE_MAP so the movable_zone initialization depends on quite some crazy movable init code paths. So maybe that is the place to look at. > BTW I just noticed that the reported memory sizes look pretty crazy: > > Memory: 3926480K/3987424K available (5254K kernel code, 561K rwdata, > 2156K rodata, 572K init, 9308K bss, 56848K reserved, > 4096K cma-reserved, 3078532K highmem) > > vs. > > Memory: 7001976K/3987424K available (5254K kernel code, 561K rwdata, > 2156K rodata, 572K init, 9308K bss, 4291097664K reserved, > 4096K cma-reserved, 7005012K highmem) This smells like a fallout. Reserved pages clearly underflowed which suggested we are initializating more than we should. -- Michal Hocko SUSE Labs