From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Hildenbrand Date: Tue, 01 Oct 2019 14:57:54 +0000 Subject: Re: [PATCH v5 01/10] mm/memunmap: Use the correct start and end pfn when removing pages from zone Message-Id: <933f9cd8-9a32-8566-bd97-7e475a009275@redhat.com> List-Id: References: <20191001144011.3801-1-david@redhat.com> <20191001144011.3801-2-david@redhat.com> In-Reply-To: <20191001144011.3801-2-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-kernel@vger.kernel.org, Dan Williams Cc: linux-s390@vger.kernel.org, linux-ia64@vger.kernel.org, Ira Weiny , linux-sh@vger.kernel.org, Jason Gunthorpe , "Aneesh Kumar K.V" , Pankaj Gupta , linux-mm@kvack.org, Logan Gunthorpe , Andrew Morton , linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org On 01.10.19 16:40, David Hildenbrand wrote: > From: "Aneesh Kumar K.V" > > With altmap, all the resource pfns are not initialized. While initializing > pfn, altmap reserve space is skipped. Hence when removing pfn from zone > skip pfns that were never initialized. > > Update memunmap_pages to calculate start and end pfn based on altmap > values. This fixes a kernel crash that is observed when destroying > a namespace. > > [ 81.356173] kernel BUG at include/linux/mm.h:1107! > cpu 0x1: Vector: 700 (Program Check) at [c000000274087890] > pc: c0000000004b9728: memunmap_pages+0x238/0x340 > lr: c0000000004b9724: memunmap_pages+0x234/0x340 > ... > pid = 3669, comm = ndctl > kernel BUG at include/linux/mm.h:1107! > [c000000274087ba0] c0000000009e3500 devm_action_release+0x30/0x50 > [c000000274087bc0] c0000000009e4758 release_nodes+0x268/0x2d0 > [c000000274087c30] c0000000009dd144 device_release_driver_internal+0x174/0x240 > [c000000274087c70] c0000000009d9dfc unbind_store+0x13c/0x190 > [c000000274087cb0] c0000000009d8a24 drv_attr_store+0x44/0x60 > [c000000274087cd0] c0000000005a7470 sysfs_kf_write+0x70/0xa0 > [c000000274087d10] c0000000005a5cac kernfs_fop_write+0x1ac/0x290 > [c000000274087d60] c0000000004be45c __vfs_write+0x3c/0x70 > [c000000274087d80] c0000000004c26e4 vfs_write+0xe4/0x200 > [c000000274087dd0] c0000000004c2a6c ksys_write+0x7c/0x140 > [c000000274087e20] c00000000000bbd0 system_call+0x5c/0x68 > > Cc: Dan Williams > Cc: Andrew Morton > Cc: Jason Gunthorpe > Cc: Logan Gunthorpe > Cc: Ira Weiny > Reviewed-by: Pankaj Gupta > Signed-off-by: Aneesh Kumar K.V > [ move all pfn-realted declarations into a single line ] > Signed-off-by: David Hildenbrand > --- > mm/memremap.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/mm/memremap.c b/mm/memremap.c > index 557e53c6fb46..026788b2ac69 100644 > --- a/mm/memremap.c > +++ b/mm/memremap.c > @@ -123,7 +123,7 @@ static void dev_pagemap_cleanup(struct dev_pagemap *pgmap) > void memunmap_pages(struct dev_pagemap *pgmap) > { > struct resource *res = &pgmap->res; > - unsigned long pfn; > + unsigned long pfn, nr_pages, start_pfn, end_pfn; > int nid; > > dev_pagemap_kill(pgmap); > @@ -131,14 +131,17 @@ void memunmap_pages(struct dev_pagemap *pgmap) > put_page(pfn_to_page(pfn)); > dev_pagemap_cleanup(pgmap); > > + start_pfn = pfn_first(pgmap); > + end_pfn = pfn_end(pgmap); > + nr_pages = end_pfn - start_pfn; > + > /* pages are dead and unused, undo the arch mapping */ > - nid = page_to_nid(pfn_to_page(PHYS_PFN(res->start))); > + nid = page_to_nid(pfn_to_page(start_pfn)); > > mem_hotplug_begin(); > if (pgmap->type = MEMORY_DEVICE_PRIVATE) { > - pfn = PHYS_PFN(res->start); > - __remove_pages(page_zone(pfn_to_page(pfn)), pfn, > - PHYS_PFN(resource_size(res)), NULL); > + __remove_pages(page_zone(pfn_to_page(start_pfn)), start_pfn, > + nr_pages, NULL); > } else { > arch_remove_memory(nid, res->start, resource_size(res), > pgmap_altmap(pgmap)); > Aneesh, I was wondering why the use of "res->start" is correct (and we shouldn't also witch to start_pfn/nr_pages here. It would be good if Dan could review. -- Thanks, David / dhildenb From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE44FC352AA for ; Tue, 1 Oct 2019 14:57:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A7CC4215EA for ; Tue, 1 Oct 2019 14:57:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389566AbfJAO57 (ORCPT ); Tue, 1 Oct 2019 10:57:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48604 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389029AbfJAO56 (ORCPT ); Tue, 1 Oct 2019 10:57:58 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B3B368A1C8D; Tue, 1 Oct 2019 14:57:57 +0000 (UTC) Received: from [10.36.116.54] (ovpn-116-54.ams2.redhat.com [10.36.116.54]) by smtp.corp.redhat.com (Postfix) with ESMTP id 09EA96012C; Tue, 1 Oct 2019 14:57:54 +0000 (UTC) Subject: Re: [PATCH v5 01/10] mm/memunmap: Use the correct start and end pfn when removing pages from zone To: linux-kernel@vger.kernel.org, Dan Williams Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, "Aneesh Kumar K.V" , Andrew Morton , Jason Gunthorpe , Logan Gunthorpe , Ira Weiny , Pankaj Gupta References: <20191001144011.3801-1-david@redhat.com> <20191001144011.3801-2-david@redhat.com> From: David Hildenbrand Openpgp: preference=signencrypt Autocrypt: addr=david@redhat.com; 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Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20191001144011.3801-2-david@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.69]); Tue, 01 Oct 2019 14:57:57 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01.10.19 16:40, David Hildenbrand wrote: > From: "Aneesh Kumar K.V" > > With altmap, all the resource pfns are not initialized. While initializing > pfn, altmap reserve space is skipped. Hence when removing pfn from zone > skip pfns that were never initialized. > > Update memunmap_pages to calculate start and end pfn based on altmap > values. This fixes a kernel crash that is observed when destroying > a namespace. > > [ 81.356173] kernel BUG at include/linux/mm.h:1107! > cpu 0x1: Vector: 700 (Program Check) at [c000000274087890] > pc: c0000000004b9728: memunmap_pages+0x238/0x340 > lr: c0000000004b9724: memunmap_pages+0x234/0x340 > ... > pid = 3669, comm = ndctl > kernel BUG at include/linux/mm.h:1107! > [c000000274087ba0] c0000000009e3500 devm_action_release+0x30/0x50 > [c000000274087bc0] c0000000009e4758 release_nodes+0x268/0x2d0 > [c000000274087c30] c0000000009dd144 device_release_driver_internal+0x174/0x240 > [c000000274087c70] c0000000009d9dfc unbind_store+0x13c/0x190 > [c000000274087cb0] c0000000009d8a24 drv_attr_store+0x44/0x60 > [c000000274087cd0] c0000000005a7470 sysfs_kf_write+0x70/0xa0 > [c000000274087d10] c0000000005a5cac kernfs_fop_write+0x1ac/0x290 > [c000000274087d60] c0000000004be45c __vfs_write+0x3c/0x70 > [c000000274087d80] c0000000004c26e4 vfs_write+0xe4/0x200 > [c000000274087dd0] c0000000004c2a6c ksys_write+0x7c/0x140 > [c000000274087e20] c00000000000bbd0 system_call+0x5c/0x68 > > Cc: Dan Williams > Cc: Andrew Morton > Cc: Jason Gunthorpe > Cc: Logan Gunthorpe > Cc: Ira Weiny > Reviewed-by: Pankaj Gupta > Signed-off-by: Aneesh Kumar K.V > [ move all pfn-realted declarations into a single line ] > Signed-off-by: David Hildenbrand > --- > mm/memremap.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/mm/memremap.c b/mm/memremap.c > index 557e53c6fb46..026788b2ac69 100644 > --- a/mm/memremap.c > +++ b/mm/memremap.c > @@ -123,7 +123,7 @@ static void dev_pagemap_cleanup(struct dev_pagemap *pgmap) > void memunmap_pages(struct dev_pagemap *pgmap) > { > struct resource *res = &pgmap->res; > - unsigned long pfn; > + unsigned long pfn, nr_pages, start_pfn, end_pfn; > int nid; > > dev_pagemap_kill(pgmap); > @@ -131,14 +131,17 @@ void memunmap_pages(struct dev_pagemap *pgmap) > put_page(pfn_to_page(pfn)); > dev_pagemap_cleanup(pgmap); > > + start_pfn = pfn_first(pgmap); > + end_pfn = pfn_end(pgmap); > + nr_pages = end_pfn - start_pfn; > + > /* pages are dead and unused, undo the arch mapping */ > - nid = page_to_nid(pfn_to_page(PHYS_PFN(res->start))); > + nid = page_to_nid(pfn_to_page(start_pfn)); > > mem_hotplug_begin(); > if (pgmap->type == MEMORY_DEVICE_PRIVATE) { > - pfn = PHYS_PFN(res->start); > - __remove_pages(page_zone(pfn_to_page(pfn)), pfn, > - PHYS_PFN(resource_size(res)), NULL); > + __remove_pages(page_zone(pfn_to_page(start_pfn)), start_pfn, > + nr_pages, NULL); > } else { > arch_remove_memory(nid, res->start, resource_size(res), > pgmap_altmap(pgmap)); > Aneesh, I was wondering why the use of "res->start" is correct (and we shouldn't also witch to start_pfn/nr_pages here. It would be good if Dan could review. -- Thanks, David / dhildenb From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 66186ECE587 for ; Tue, 1 Oct 2019 15:18:14 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DB9C82133F for ; Tue, 1 Oct 2019 15:18:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DB9C82133F Authentication-Results: mail.kernel.org; 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Tue, 1 Oct 2019 14:57:57 +0000 (UTC) Received: from [10.36.116.54] (ovpn-116-54.ams2.redhat.com [10.36.116.54]) by smtp.corp.redhat.com (Postfix) with ESMTP id 09EA96012C; Tue, 1 Oct 2019 14:57:54 +0000 (UTC) Subject: Re: [PATCH v5 01/10] mm/memunmap: Use the correct start and end pfn when removing pages from zone To: linux-kernel@vger.kernel.org, Dan Williams References: <20191001144011.3801-1-david@redhat.com> <20191001144011.3801-2-david@redhat.com> From: David Hildenbrand Openpgp: preference=signencrypt Autocrypt: addr=david@redhat.com; prefer-encrypt=mutual; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwX4EEwECACgFAljj9eoCGwMFCQlmAYAGCwkI BwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEE3eEPcA/4Na5IIP/3T/FIQMxIfNzZshIq687qgG 8UbspuE/YSUDdv7r5szYTK6KPTlqN8NAcSfheywbuYD9A4ZeSBWD3/NAVUdrCaRP2IvFyELj xoMvfJccbq45BxzgEspg/bVahNbyuBpLBVjVWwRtFCUEXkyazksSv8pdTMAs9IucChvFmmq3 jJ2vlaz9lYt/lxN246fIVceckPMiUveimngvXZw21VOAhfQ+/sofXF8JCFv2mFcBDoa7eYob s0FLpmqFaeNRHAlzMWgSsP80qx5nWWEvRLdKWi533N2vC/EyunN3HcBwVrXH4hxRBMco3jvM m8VKLKao9wKj82qSivUnkPIwsAGNPdFoPbgghCQiBjBe6A75Z2xHFrzo7t1jg7nQfIyNC7ez MZBJ59sqA9EDMEJPlLNIeJmqslXPjmMFnE7Mby/+335WJYDulsRybN+W5rLT5aMvhC6x6POK z55fMNKrMASCzBJum2Fwjf/VnuGRYkhKCqqZ8gJ3OvmR50tInDV2jZ1DQgc3i550T5JDpToh dPBxZocIhzg+MBSRDXcJmHOx/7nQm3iQ6iLuwmXsRC6f5FbFefk9EjuTKcLMvBsEx+2DEx0E UnmJ4hVg7u1PQ+2Oy+Lh/opK/BDiqlQ8Pz2jiXv5xkECvr/3Sv59hlOCZMOaiLTTjtOIU7Tq 7ut6OL64oAq+zsFNBFXLn5EBEADn1959INH2cwYJv0tsxf5MUCghCj/CA/lc/LMthqQ773ga uB9mN+F1rE9cyyXb6jyOGn+GUjMbnq1o121Vm0+neKHUCBtHyseBfDXHA6m4B3mUTWo13nid 0e4AM71r0DS8+KYh6zvweLX/LL5kQS9GQeT+QNroXcC1NzWbitts6TZ+IrPOwT1hfB4WNC+X 2n4AzDqp3+ILiVST2DT4VBc11Gz6jijpC/KI5Al8ZDhRwG47LUiuQmt3yqrmN63V9wzaPhC+ xbwIsNZlLUvuRnmBPkTJwwrFRZvwu5GPHNndBjVpAfaSTOfppyKBTccu2AXJXWAE1Xjh6GOC 8mlFjZwLxWFqdPHR1n2aPVgoiTLk34LR/bXO+e0GpzFXT7enwyvFFFyAS0Nk1q/7EChPcbRb hJqEBpRNZemxmg55zC3GLvgLKd5A09MOM2BrMea+l0FUR+PuTenh2YmnmLRTro6eZ/qYwWkC u8FFIw4pT0OUDMyLgi+GI1aMpVogTZJ70FgV0pUAlpmrzk/bLbRkF3TwgucpyPtcpmQtTkWS gDS50QG9DR/1As3LLLcNkwJBZzBG6PWbvcOyrwMQUF1nl4SSPV0LLH63+BrrHasfJzxKXzqg rW28CTAE2x8qi7e/6M/+XXhrsMYG+uaViM7n2je3qKe7ofum3s4vq7oFCPsOgwARAQABwsFl BBgBAgAPBQJVy5+RAhsMBQkJZgGAAAoJEE3eEPcA/4NagOsP/jPoIBb/iXVbM+fmSHOjEshl KMwEl/m5iLj3iHnHPVLBUWrXPdS7iQijJA/VLxjnFknhaS60hkUNWexDMxVVP/6lbOrs4bDZ NEWDMktAeqJaFtxackPszlcpRVkAs6Msn9tu8hlvB517pyUgvuD7ZS9gGOMmYwFQDyytpepo YApVV00P0u3AaE0Cj/o71STqGJKZxcVhPaZ+LR+UCBZOyKfEyq+ZN311VpOJZ1IvTExf+S/5 lqnciDtbO3I4Wq0ArLX1gs1q1XlXLaVaA3yVqeC8E7kOchDNinD3hJS4OX0e1gdsx/e6COvy qNg5aL5n0Kl4fcVqM0LdIhsubVs4eiNCa5XMSYpXmVi3HAuFyg9dN+x8thSwI836FoMASwOl C7tHsTjnSGufB+D7F7ZBT61BffNBBIm1KdMxcxqLUVXpBQHHlGkbwI+3Ye+nE6HmZH7IwLwV W+Ajl7oYF+jeKaH4DZFtgLYGLtZ1LDwKPjX7VAsa4Yx7S5+EBAaZGxK510MjIx6SGrZWBrrV TEvdV00F2MnQoeXKzD7O4WFbL55hhyGgfWTHwZ457iN9SgYi1JLPqWkZB0JRXIEtjd4JEQcx +8Umfre0Xt4713VxMygW0PnQt5aSQdMD58jHFxTk092mU+yIHj5LeYgvwSgZN4airXk5yRXl SE+xAvmumFBY Organization: Red Hat GmbH Message-ID: <933f9cd8-9a32-8566-bd97-7e475a009275@redhat.com> Date: Tue, 1 Oct 2019 16:57:54 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20191001144011.3801-2-david@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.69]); Tue, 01 Oct 2019 14:57:57 +0000 (UTC) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-s390@vger.kernel.org, linux-ia64@vger.kernel.org, Ira Weiny , linux-sh@vger.kernel.org, Jason Gunthorpe , "Aneesh Kumar K.V" , Pankaj Gupta , linux-mm@kvack.org, Logan Gunthorpe , Andrew Morton , linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 01.10.19 16:40, David Hildenbrand wrote: > From: "Aneesh Kumar K.V" > > With altmap, all the resource pfns are not initialized. While initializing > pfn, altmap reserve space is skipped. Hence when removing pfn from zone > skip pfns that were never initialized. > > Update memunmap_pages to calculate start and end pfn based on altmap > values. This fixes a kernel crash that is observed when destroying > a namespace. > > [ 81.356173] kernel BUG at include/linux/mm.h:1107! > cpu 0x1: Vector: 700 (Program Check) at [c000000274087890] > pc: c0000000004b9728: memunmap_pages+0x238/0x340 > lr: c0000000004b9724: memunmap_pages+0x234/0x340 > ... > pid = 3669, comm = ndctl > kernel BUG at include/linux/mm.h:1107! > [c000000274087ba0] c0000000009e3500 devm_action_release+0x30/0x50 > [c000000274087bc0] c0000000009e4758 release_nodes+0x268/0x2d0 > [c000000274087c30] c0000000009dd144 device_release_driver_internal+0x174/0x240 > [c000000274087c70] c0000000009d9dfc unbind_store+0x13c/0x190 > [c000000274087cb0] c0000000009d8a24 drv_attr_store+0x44/0x60 > [c000000274087cd0] c0000000005a7470 sysfs_kf_write+0x70/0xa0 > [c000000274087d10] c0000000005a5cac kernfs_fop_write+0x1ac/0x290 > [c000000274087d60] c0000000004be45c __vfs_write+0x3c/0x70 > [c000000274087d80] c0000000004c26e4 vfs_write+0xe4/0x200 > [c000000274087dd0] c0000000004c2a6c ksys_write+0x7c/0x140 > [c000000274087e20] c00000000000bbd0 system_call+0x5c/0x68 > > Cc: Dan Williams > Cc: Andrew Morton > Cc: Jason Gunthorpe > Cc: Logan Gunthorpe > Cc: Ira Weiny > Reviewed-by: Pankaj Gupta > Signed-off-by: Aneesh Kumar K.V > [ move all pfn-realted declarations into a single line ] > Signed-off-by: David Hildenbrand > --- > mm/memremap.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/mm/memremap.c b/mm/memremap.c > index 557e53c6fb46..026788b2ac69 100644 > --- a/mm/memremap.c > +++ b/mm/memremap.c > @@ -123,7 +123,7 @@ static void dev_pagemap_cleanup(struct dev_pagemap *pgmap) > void memunmap_pages(struct dev_pagemap *pgmap) > { > struct resource *res = &pgmap->res; > - unsigned long pfn; > + unsigned long pfn, nr_pages, start_pfn, end_pfn; > int nid; > > dev_pagemap_kill(pgmap); > @@ -131,14 +131,17 @@ void memunmap_pages(struct dev_pagemap *pgmap) > put_page(pfn_to_page(pfn)); > dev_pagemap_cleanup(pgmap); > > + start_pfn = pfn_first(pgmap); > + end_pfn = pfn_end(pgmap); > + nr_pages = end_pfn - start_pfn; > + > /* pages are dead and unused, undo the arch mapping */ > - nid = page_to_nid(pfn_to_page(PHYS_PFN(res->start))); > + nid = page_to_nid(pfn_to_page(start_pfn)); > > mem_hotplug_begin(); > if (pgmap->type == MEMORY_DEVICE_PRIVATE) { > - pfn = PHYS_PFN(res->start); > - __remove_pages(page_zone(pfn_to_page(pfn)), pfn, > - PHYS_PFN(resource_size(res)), NULL); > + __remove_pages(page_zone(pfn_to_page(start_pfn)), start_pfn, > + nr_pages, NULL); > } else { > arch_remove_memory(nid, res->start, resource_size(res), > pgmap_altmap(pgmap)); > Aneesh, I was wondering why the use of "res->start" is correct (and we shouldn't also witch to start_pfn/nr_pages here. It would be good if Dan could review. -- Thanks, David / dhildenb From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 34098C352AA for ; Tue, 1 Oct 2019 14:58:08 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0C33A215EA for ; Tue, 1 Oct 2019 14:58:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="ggGWgkTa" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0C33A215EA Authentication-Results: mail.kernel.org; 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Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20191001144011.3801-2-david@redhat.com> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.69]); Tue, 01 Oct 2019 14:57:57 +0000 (UTC) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191001_075758_245503_2817EF72 X-CRM114-Status: GOOD ( 25.79 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-s390@vger.kernel.org, linux-ia64@vger.kernel.org, Ira Weiny , linux-sh@vger.kernel.org, Jason Gunthorpe , "Aneesh Kumar K.V" , Pankaj Gupta , linux-mm@kvack.org, Logan Gunthorpe , Andrew Morton , linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 01.10.19 16:40, David Hildenbrand wrote: > From: "Aneesh Kumar K.V" > > With altmap, all the resource pfns are not initialized. While initializing > pfn, altmap reserve space is skipped. Hence when removing pfn from zone > skip pfns that were never initialized. > > Update memunmap_pages to calculate start and end pfn based on altmap > values. This fixes a kernel crash that is observed when destroying > a namespace. > > [ 81.356173] kernel BUG at include/linux/mm.h:1107! > cpu 0x1: Vector: 700 (Program Check) at [c000000274087890] > pc: c0000000004b9728: memunmap_pages+0x238/0x340 > lr: c0000000004b9724: memunmap_pages+0x234/0x340 > ... > pid = 3669, comm = ndctl > kernel BUG at include/linux/mm.h:1107! > [c000000274087ba0] c0000000009e3500 devm_action_release+0x30/0x50 > [c000000274087bc0] c0000000009e4758 release_nodes+0x268/0x2d0 > [c000000274087c30] c0000000009dd144 device_release_driver_internal+0x174/0x240 > [c000000274087c70] c0000000009d9dfc unbind_store+0x13c/0x190 > [c000000274087cb0] c0000000009d8a24 drv_attr_store+0x44/0x60 > [c000000274087cd0] c0000000005a7470 sysfs_kf_write+0x70/0xa0 > [c000000274087d10] c0000000005a5cac kernfs_fop_write+0x1ac/0x290 > [c000000274087d60] c0000000004be45c __vfs_write+0x3c/0x70 > [c000000274087d80] c0000000004c26e4 vfs_write+0xe4/0x200 > [c000000274087dd0] c0000000004c2a6c ksys_write+0x7c/0x140 > [c000000274087e20] c00000000000bbd0 system_call+0x5c/0x68 > > Cc: Dan Williams > Cc: Andrew Morton > Cc: Jason Gunthorpe > Cc: Logan Gunthorpe > Cc: Ira Weiny > Reviewed-by: Pankaj Gupta > Signed-off-by: Aneesh Kumar K.V > [ move all pfn-realted declarations into a single line ] > Signed-off-by: David Hildenbrand > --- > mm/memremap.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/mm/memremap.c b/mm/memremap.c > index 557e53c6fb46..026788b2ac69 100644 > --- a/mm/memremap.c > +++ b/mm/memremap.c > @@ -123,7 +123,7 @@ static void dev_pagemap_cleanup(struct dev_pagemap *pgmap) > void memunmap_pages(struct dev_pagemap *pgmap) > { > struct resource *res = &pgmap->res; > - unsigned long pfn; > + unsigned long pfn, nr_pages, start_pfn, end_pfn; > int nid; > > dev_pagemap_kill(pgmap); > @@ -131,14 +131,17 @@ void memunmap_pages(struct dev_pagemap *pgmap) > put_page(pfn_to_page(pfn)); > dev_pagemap_cleanup(pgmap); > > + start_pfn = pfn_first(pgmap); > + end_pfn = pfn_end(pgmap); > + nr_pages = end_pfn - start_pfn; > + > /* pages are dead and unused, undo the arch mapping */ > - nid = page_to_nid(pfn_to_page(PHYS_PFN(res->start))); > + nid = page_to_nid(pfn_to_page(start_pfn)); > > mem_hotplug_begin(); > if (pgmap->type == MEMORY_DEVICE_PRIVATE) { > - pfn = PHYS_PFN(res->start); > - __remove_pages(page_zone(pfn_to_page(pfn)), pfn, > - PHYS_PFN(resource_size(res)), NULL); > + __remove_pages(page_zone(pfn_to_page(start_pfn)), start_pfn, > + nr_pages, NULL); > } else { > arch_remove_memory(nid, res->start, resource_size(res), > pgmap_altmap(pgmap)); > Aneesh, I was wondering why the use of "res->start" is correct (and we shouldn't also witch to start_pfn/nr_pages here. It would be good if Dan could review. -- Thanks, David / dhildenb _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel