Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753277Ab3H0QG3 (ORCPT ); Tue, 27 Aug 2013 12:06:29 -0400 Received: from relay3.sgi.com ([192.48.152.1]:57818 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751745Ab3H0QG1 (ORCPT ); Tue, 27 Aug 2013 12:06:27 -0400 Date: Tue, 27 Aug 2013 11:06:25 -0500 From: Russ Anderson To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Greg Kroah-Hartman , "Rafael J. Wysocki" , Yinghai Lu , Yasuaki Ishimatsu Subject: Re: [PATCH v2] [BUGFIX] drivers/base: fix show_mem_removable to handle missing sections Message-ID: <20130827160624.GA22918@sgi.com> Reply-To: Russ Anderson References: <20130823162317.GB10988@sgi.com> <20130826144959.52fd24cd2833929168ee7e35@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130826144959.52fd24cd2833929168ee7e35@linux-foundation.org> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1313 Lines: 32 On Mon, Aug 26, 2013 at 02:49:59PM -0700, Andrew Morton wrote: > On Fri, 23 Aug 2013 11:23:17 -0500 Russ Anderson wrote: > > > "cat /sys/devices/system/memory/memory*/removable" crashed the system. > > > > The problem is that show_mem_removable() is passing a > > bad pfn to is_mem_section_removable(), which causes > > if (!node_online(page_to_nid(page))) to blow up. > > Why is it passing in a bad pfn? > > > > show_mem_removable() will loop sections_per_block times. > > sections_per_block is 16, but mem->section_count is 8, > > indicating holes in this memory block. Checking that > > the memory section is present before checking to see > > if the memory section is removable fixes the problem. > > The patch textually applies to 3.10, 3.9 and perhaps earlier. Should > it be applied to earlier kernels? I believe so, since this does not appear to be a recent regression, but have not verified the problem/fix in earlier kernels. Thanks, -- Russ Anderson, OS RAS/Partitioning Project Lead SGI - Silicon Graphics Inc rja@sgi.com -- 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/