From patchwork Tue Sep 29 16:22:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Laurent Dufour X-Patchwork-Id: 262862 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 C4AA1C4741F for ; Tue, 29 Sep 2020 16:23:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5C2FE20C09 for ; Tue, 29 Sep 2020 16:23:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="o5nSIXqp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728126AbgI2QXM (ORCPT ); Tue, 29 Sep 2020 12:23:12 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:45154 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728184AbgI2QXL (ORCPT ); Tue, 29 Sep 2020 12:23:11 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 08TG2ZWL185255; Tue, 29 Sep 2020 12:23:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=Q2fDwe0V334Hs7q7rbQr16b4xXkcVJhjktmD/mZMrLE=; b=o5nSIXqpOtcAfWk3LxkyyMQRvGSFNcN6h4i0TCJJoTE3sZueWV13YZkrQTUvTkRIKgC+ wTeD7EkT445aHd/J5oo6f9NkeN/1/R+p7rVem2Mx857A8yo/IfcpRxIw7I5oz+g44PBv +EQMQdQJWAEW3COXVpWuc+Ts51Iuv5+aGukstkLBssvEIX/6UAvGAhInopSmEsc+HWrw rx/oLz5ZOqW6JKqTUQ7jAiUyffZVMpky5dAxIY5atrv0tH5NfieMBrI+0hzs1yMsx/I2 HAhgyWkNQTdSHtZyLHUwCOEOWy3lGu3qNl5XlCfPWwfQYTgnlZuH04HlFh8c9Y9//ZIz og== Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 33v6kbmdh7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 29 Sep 2020 12:23:00 -0400 Received: from m0098414.ppops.net (m0098414.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 08TG37HL188358; Tue, 29 Sep 2020 12:22:57 -0400 Received: from ppma03fra.de.ibm.com (6b.4a.5195.ip4.static.sl-reverse.com [149.81.74.107]) by mx0b-001b2d01.pphosted.com with ESMTP id 33v6kbmdge-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 29 Sep 2020 12:22:57 -0400 Received: from pps.filterd (ppma03fra.de.ibm.com [127.0.0.1]) by ppma03fra.de.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 08TGLfnQ005465; Tue, 29 Sep 2020 16:22:55 GMT Received: from b06avi18626390.portsmouth.uk.ibm.com (b06avi18626390.portsmouth.uk.ibm.com [9.149.26.192]) by ppma03fra.de.ibm.com with ESMTP id 33v5kg03qe-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 29 Sep 2020 16:22:55 +0000 Received: from d06av24.portsmouth.uk.ibm.com (mk.ibm.com [9.149.105.60]) by b06avi18626390.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 08TGMqd132964872 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 29 Sep 2020 16:22:52 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8306942041; Tue, 29 Sep 2020 16:22:52 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0FA7D42047; Tue, 29 Sep 2020 16:22:52 +0000 (GMT) Received: from pomme.tlslab.ibm.com (unknown [9.145.50.8]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 29 Sep 2020 16:22:51 +0000 (GMT) From: Laurent Dufour To: stable@vger.kernel.org Cc: David Hildenbrand , Andrew Morton , Oscar Salvador , Michal Hocko , Greg Kroah-Hartman , "Rafael J . Wysocki" , Nathan Lynch , Scott Cheloha , Tony Luck , Fenghua Yu , Linus Torvalds Subject: [PATCH 1/2] mm: replace memmap_context by memplug_context Date: Tue, 29 Sep 2020 18:22:49 +0200 Message-Id: <20200929162250.67282-1-ldufour@linux.ibm.com> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235, 18.0.687 definitions=2020-09-29_07:2020-09-29,2020-09-29 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 phishscore=0 priorityscore=1501 lowpriorityscore=0 suspectscore=0 adultscore=0 clxscore=1015 mlxscore=0 mlxlogscore=999 bulkscore=0 impostorscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2009290136 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Backport version to the 4.19-stable tree of: [ Upstream commit c1d0da83358a2316d9be7f229f26126dbaa07468 ] Patch series "mm: fix memory to node bad links in sysfs", v3. Sometimes, firmware may expose interleaved memory layout like this: Early memory node ranges node 1: [mem 0x0000000000000000-0x000000011fffffff] node 2: [mem 0x0000000120000000-0x000000014fffffff] node 1: [mem 0x0000000150000000-0x00000001ffffffff] node 0: [mem 0x0000000200000000-0x000000048fffffff] node 2: [mem 0x0000000490000000-0x00000007ffffffff] In that case, we can see memory blocks assigned to multiple nodes in sysfs: $ ls -l /sys/devices/system/memory/memory21 total 0 lrwxrwxrwx 1 root root 0 Aug 24 05:27 node1 -> ../../node/node1 lrwxrwxrwx 1 root root 0 Aug 24 05:27 node2 -> ../../node/node2 -rw-r--r-- 1 root root 65536 Aug 24 05:27 online -r--r--r-- 1 root root 65536 Aug 24 05:27 phys_device -r--r--r-- 1 root root 65536 Aug 24 05:27 phys_index drwxr-xr-x 2 root root 0 Aug 24 05:27 power -r--r--r-- 1 root root 65536 Aug 24 05:27 removable -rw-r--r-- 1 root root 65536 Aug 24 05:27 state lrwxrwxrwx 1 root root 0 Aug 24 05:25 subsystem -> ../../../../bus/memory -rw-r--r-- 1 root root 65536 Aug 24 05:25 uevent -r--r--r-- 1 root root 65536 Aug 24 05:27 valid_zones The same applies in the node's directory with a memory21 link in both the node1 and node2's directory. This is wrong but doesn't prevent the system to run. However when later, one of these memory blocks is hot-unplugged and then hot-plugged, the system is detecting an inconsistency in the sysfs layout and a BUG_ON() is raised: kernel BUG at /Users/laurent/src/linux-ppc/mm/memory_hotplug.c:1084! LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: rpadlpar_io rpaphp pseries_rng rng_core vmx_crypto gf128mul binfmt_misc ip_tables x_tables xfs libcrc32c crc32c_vpmsum autofs4 CPU: 8 PID: 10256 Comm: drmgr Not tainted 5.9.0-rc1+ #25 Call Trace: add_memory_resource+0x23c/0x340 (unreliable) __add_memory+0x5c/0xf0 dlpar_add_lmb+0x1b4/0x500 dlpar_memory+0x1f8/0xb80 handle_dlpar_errorlog+0xc0/0x190 dlpar_store+0x198/0x4a0 kobj_attr_store+0x30/0x50 sysfs_kf_write+0x64/0x90 kernfs_fop_write+0x1b0/0x290 vfs_write+0xe8/0x290 ksys_write+0xdc/0x130 system_call_exception+0x160/0x270 system_call_common+0xf0/0x27c This has been seen on PowerPC LPAR. The root cause of this issue is that when node's memory is registered, the range used can overlap another node's range, thus the memory block is registered to multiple nodes in sysfs. There are two issues here: (a) The sysfs memory and node's layouts are broken due to these multiple links (b) The link errors in link_mem_sections() should not lead to a system panic. To address (a) register_mem_sect_under_node should not rely on the system state to detect whether the link operation is triggered by a hot plug operation or not. This is addressed by the patches 1 and 2 of this series. Issue (b) will be addressed separately. This patch (of 2): The memmap_context enum is used to detect whether a memory operation is due to a hot-add operation or happening at boot time. Make it general to the hotplug operation and rename it as meminit_context. There is no functional change introduced by this patch Suggested-by: David Hildenbrand Signed-off-by: Laurent Dufour Signed-off-by: Andrew Morton Reviewed-by: David Hildenbrand Reviewed-by: Oscar Salvador Acked-by: Michal Hocko Cc: Greg Kroah-Hartman Cc: "Rafael J . Wysocki" Cc: Nathan Lynch Cc: Scott Cheloha Cc: Tony Luck Cc: Fenghua Yu Cc: # 4.19.y Link: https://lkml.kernel.org/r/20200915094143.79181-1-ldufour@linux.ibm.com Link: https://lkml.kernel.org/r/20200915132624.9723-1-ldufour@linux.ibm.com Signed-off-by: Linus Torvalds --- arch/ia64/mm/init.c | 6 +++--- include/linux/mm.h | 2 +- include/linux/mmzone.h | 11 ++++++++--- mm/memory_hotplug.c | 2 +- mm/page_alloc.c | 11 ++++++----- 5 files changed, 19 insertions(+), 13 deletions(-) diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c index 79e5cc70f1fd..561e2573bd34 100644 --- a/arch/ia64/mm/init.c +++ b/arch/ia64/mm/init.c @@ -499,7 +499,7 @@ virtual_memmap_init(u64 start, u64 end, void *arg) if (map_start < map_end) memmap_init_zone((unsigned long)(map_end - map_start), args->nid, args->zone, page_to_pfn(map_start), - MEMMAP_EARLY, NULL); + MEMINIT_EARLY, NULL); return 0; } @@ -508,8 +508,8 @@ memmap_init (unsigned long size, int nid, unsigned long zone, unsigned long start_pfn) { if (!vmem_map) { - memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY, - NULL); + memmap_init_zone(size, nid, zone, start_pfn, + MEMINIT_EARLY, NULL); } else { struct page *start; struct memmap_init_callback_data args; diff --git a/include/linux/mm.h b/include/linux/mm.h index 05bc5f25ab85..83828c118b6b 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2179,7 +2179,7 @@ static inline void zero_resv_unavail(void) {} extern void set_dma_reserve(unsigned long new_dma_reserve); extern void memmap_init_zone(unsigned long, int, unsigned long, unsigned long, - enum memmap_context, struct vmem_altmap *); + enum meminit_context, struct vmem_altmap *); extern void setup_per_zone_wmarks(void); extern int __meminit init_per_zone_wmark_min(void); extern void mem_init(void); diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index fdd93a39f1fa..fa02014eba8e 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -759,10 +759,15 @@ bool zone_watermark_ok(struct zone *z, unsigned int order, unsigned int alloc_flags); bool zone_watermark_ok_safe(struct zone *z, unsigned int order, unsigned long mark, int classzone_idx); -enum memmap_context { - MEMMAP_EARLY, - MEMMAP_HOTPLUG, +/* + * Memory initialization context, use to differentiate memory added by + * the platform statically or via memory hotplug interface. + */ +enum meminit_context { + MEMINIT_EARLY, + MEMINIT_HOTPLUG, }; + extern void init_currently_empty_zone(struct zone *zone, unsigned long start_pfn, unsigned long size); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index aae7ff485671..c839c4ad4871 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -733,7 +733,7 @@ void __ref move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn, * are reserved so nobody should be touching them so we should be safe */ memmap_init_zone(nr_pages, nid, zone_idx(zone), start_pfn, - MEMMAP_HOTPLUG, altmap); + MEMINIT_HOTPLUG, altmap); set_zone_contiguous(zone); } diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 5717ee66c8b3..545800433dfb 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5480,7 +5480,7 @@ void __ref build_all_zonelists(pg_data_t *pgdat) * done. Non-atomic initialization, single-pass. */ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, - unsigned long start_pfn, enum memmap_context context, + unsigned long start_pfn, enum meminit_context context, struct vmem_altmap *altmap) { unsigned long end_pfn = start_pfn + size; @@ -5507,7 +5507,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, * There can be holes in boot-time mem_map[]s handed to this * function. They do not exist on hotplugged memory. */ - if (context != MEMMAP_EARLY) + if (context != MEMINIT_EARLY) goto not_early; if (!early_pfn_valid(pfn)) @@ -5542,7 +5542,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, not_early: page = pfn_to_page(pfn); __init_single_page(page, pfn, zone, nid); - if (context == MEMMAP_HOTPLUG) + if (context == MEMINIT_HOTPLUG) SetPageReserved(page); /* @@ -5557,7 +5557,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, * check here not to call set_pageblock_migratetype() against * pfn out of zone. * - * Please note that MEMMAP_HOTPLUG path doesn't clear memmap + * Please note that MEMINIT_HOTPLUG path doesn't clear memmap * because this is done early in sparse_add_one_section */ if (!(pfn & (pageblock_nr_pages - 1))) { @@ -5578,7 +5578,8 @@ static void __meminit zone_init_free_lists(struct zone *zone) #ifndef __HAVE_ARCH_MEMMAP_INIT #define memmap_init(size, nid, zone, start_pfn) \ - memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY, NULL) + memmap_init_zone((size), (nid), (zone), (start_pfn), \ + MEMINIT_EARLY, NULL) #endif static int zone_batchsize(struct zone *zone) From patchwork Tue Sep 29 16:22:50 2020 Content-Type: text/plain; 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Tue, 29 Sep 2020 16:22:53 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0548E42041; Tue, 29 Sep 2020 16:22:53 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 9017C42042; Tue, 29 Sep 2020 16:22:52 +0000 (GMT) Received: from pomme.tlslab.ibm.com (unknown [9.145.50.8]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 29 Sep 2020 16:22:52 +0000 (GMT) From: Laurent Dufour To: stable@vger.kernel.org Cc: Andrew Morton , David Hildenbrand , Oscar Salvador , Michal Hocko , Greg Kroah-Hartman , "Rafael J. Wysocki" , Fenghua Yu , Nathan Lynch , Scott Cheloha , Tony Luck , Linus Torvalds Subject: [PATCH 2/2] mm: don't rely on system state to detect hot-plug operations Date: Tue, 29 Sep 2020 18:22:50 +0200 Message-Id: <20200929162250.67282-2-ldufour@linux.ibm.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200929162250.67282-1-ldufour@linux.ibm.com> References: <20200929162250.67282-1-ldufour@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235, 18.0.687 definitions=2020-09-29_07:2020-09-29,2020-09-29 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 mlxlogscore=999 priorityscore=1501 mlxscore=0 impostorscore=0 clxscore=1015 spamscore=0 malwarescore=0 bulkscore=0 phishscore=0 adultscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2009290135 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Backport version to the 4.19-stable tree of: [ Upstream commit f85086f95fa36194eb0db5cd5c12e56801b98523 ] In register_mem_sect_under_node() the system_state's value is checked to detect whether the call is made during boot time or during an hot-plug operation. Unfortunately, that check against SYSTEM_BOOTING is wrong because regular memory is registered at SYSTEM_SCHEDULING state. In addition, memory hot-plug operation can be triggered at this system state by the ACPI [1]. So checking against the system state is not enough. The consequence is that on system with interleaved node's ranges like this: Early memory node ranges node 1: [mem 0x0000000000000000-0x000000011fffffff] node 2: [mem 0x0000000120000000-0x000000014fffffff] node 1: [mem 0x0000000150000000-0x00000001ffffffff] node 0: [mem 0x0000000200000000-0x000000048fffffff] node 2: [mem 0x0000000490000000-0x00000007ffffffff] This can be seen on PowerPC LPAR after multiple memory hot-plug and hot-unplug operations are done. At the next reboot the node's memory ranges can be interleaved and since the call to link_mem_sections() is made in topology_init() while the system is in the SYSTEM_SCHEDULING state, the node's id is not checked, and the sections registered to multiple nodes: $ ls -l /sys/devices/system/memory/memory21/node* total 0 lrwxrwxrwx 1 root root 0 Aug 24 05:27 node1 -> ../../node/node1 lrwxrwxrwx 1 root root 0 Aug 24 05:27 node2 -> ../../node/node2 In that case, the system is able to boot but if later one of theses memory blocks is hot-unplugged and then hot-plugged, the sysfs inconsistency is detected and this is triggering a BUG_ON(): kernel BUG at /Users/laurent/src/linux-ppc/mm/memory_hotplug.c:1084! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: rpadlpar_io rpaphp pseries_rng rng_core vmx_crypto gf128mul binfmt_misc ip_tables x_tables xfs libcrc32c crc32c_vpmsum autofs4 CPU: 8 PID: 10256 Comm: drmgr Not tainted 5.9.0-rc1+ #25 Call Trace: add_memory_resource+0x23c/0x340 (unreliable) __add_memory+0x5c/0xf0 dlpar_add_lmb+0x1b4/0x500 dlpar_memory+0x1f8/0xb80 handle_dlpar_errorlog+0xc0/0x190 dlpar_store+0x198/0x4a0 kobj_attr_store+0x30/0x50 sysfs_kf_write+0x64/0x90 kernfs_fop_write+0x1b0/0x290 vfs_write+0xe8/0x290 ksys_write+0xdc/0x130 system_call_exception+0x160/0x270 system_call_common+0xf0/0x27c This patch addresses the root cause by not relying on the system_state value to detect whether the call is due to a hot-plug operation. An extra parameter is added to link_mem_sections() detailing whether the operation is due to a hot-plug operation. [1] According to Oscar Salvador, using this qemu command line, ACPI memory hotplug operations are raised at SYSTEM_SCHEDULING state: $QEMU -enable-kvm -machine pc -smp 4,sockets=4,cores=1,threads=1 -cpu host -monitor pty \ -m size=$MEM,slots=255,maxmem=4294967296k \ -numa node,nodeid=0,cpus=0-3,mem=512 -numa node,nodeid=1,mem=512 \ -object memory-backend-ram,id=memdimm0,size=134217728 -device pc-dimm,node=0,memdev=memdimm0,id=dimm0,slot=0 \ -object memory-backend-ram,id=memdimm1,size=134217728 -device pc-dimm,node=0,memdev=memdimm1,id=dimm1,slot=1 \ -object memory-backend-ram,id=memdimm2,size=134217728 -device pc-dimm,node=0,memdev=memdimm2,id=dimm2,slot=2 \ -object memory-backend-ram,id=memdimm3,size=134217728 -device pc-dimm,node=0,memdev=memdimm3,id=dimm3,slot=3 \ -object memory-backend-ram,id=memdimm4,size=134217728 -device pc-dimm,node=1,memdev=memdimm4,id=dimm4,slot=4 \ -object memory-backend-ram,id=memdimm5,size=134217728 -device pc-dimm,node=1,memdev=memdimm5,id=dimm5,slot=5 \ -object memory-backend-ram,id=memdimm6,size=134217728 -device pc-dimm,node=1,memdev=memdimm6,id=dimm6,slot=6 \ Fixes: 4fbce633910e ("mm/memory_hotplug.c: make register_mem_sect_under_node() a callback of walk_memory_range()") Signed-off-by: Laurent Dufour Signed-off-by: Andrew Morton Reviewed-by: David Hildenbrand Reviewed-by: Oscar Salvador Acked-by: Michal Hocko Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: Fenghua Yu Cc: Nathan Lynch Cc: Scott Cheloha Cc: Tony Luck Cc: # 4.19.y Link: https://lkml.kernel.org/r/20200915094143.79181-3-ldufour@linux.ibm.com Signed-off-by: Linus Torvalds --- drivers/base/node.c | 84 ++++++++++++++++++++++++++++---------------- include/linux/node.h | 11 +++--- mm/memory_hotplug.c | 3 +- 3 files changed, 63 insertions(+), 35 deletions(-) diff --git a/drivers/base/node.c b/drivers/base/node.c index f3565c2dbc52..503e2f90e58e 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -403,10 +403,32 @@ static int __ref get_nid_for_pfn(unsigned long pfn) return pfn_to_nid(pfn); } +static int do_register_memory_block_under_node(int nid, + struct memory_block *mem_blk) +{ + int ret; + + /* + * If this memory block spans multiple nodes, we only indicate + * the last processed node. + */ + mem_blk->nid = nid; + + ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, + &mem_blk->dev.kobj, + kobject_name(&mem_blk->dev.kobj)); + if (ret) + return ret; + + return sysfs_create_link_nowarn(&mem_blk->dev.kobj, + &node_devices[nid]->dev.kobj, + kobject_name(&node_devices[nid]->dev.kobj)); +} + /* register memory section under specified node if it spans that node */ -int register_mem_sect_under_node(struct memory_block *mem_blk, void *arg) +int register_mem_block_under_node_early(struct memory_block *mem_blk, void *arg) { - int ret, nid = *(int *)arg; + int nid = *(int *)arg; unsigned long pfn, sect_start_pfn, sect_end_pfn; sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); @@ -426,38 +448,33 @@ int register_mem_sect_under_node(struct memory_block *mem_blk, void *arg) } /* - * We need to check if page belongs to nid only for the boot - * case, during hotplug we know that all pages in the memory - * block belong to the same node. - */ - if (system_state == SYSTEM_BOOTING) { - page_nid = get_nid_for_pfn(pfn); - if (page_nid < 0) - continue; - if (page_nid != nid) - continue; - } - - /* - * If this memory block spans multiple nodes, we only indicate - * the last processed node. + * We need to check if page belongs to nid only at the boot + * case because node's ranges can be interleaved. */ - mem_blk->nid = nid; - - ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, - &mem_blk->dev.kobj, - kobject_name(&mem_blk->dev.kobj)); - if (ret) - return ret; + page_nid = get_nid_for_pfn(pfn); + if (page_nid < 0) + continue; + if (page_nid != nid) + continue; - return sysfs_create_link_nowarn(&mem_blk->dev.kobj, - &node_devices[nid]->dev.kobj, - kobject_name(&node_devices[nid]->dev.kobj)); + return do_register_memory_block_under_node(nid, mem_blk); } /* mem section does not span the specified node */ return 0; } +/* + * During hotplug we know that all pages in the memory block belong to the same + * node. + */ +static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk, + void *arg) +{ + int nid = *(int *)arg; + + return do_register_memory_block_under_node(nid, mem_blk); +} + /* * Unregister a memory block device under the node it spans. Memory blocks * with multiple nodes cannot be offlined and therefore also never be removed. @@ -473,10 +490,17 @@ void unregister_memory_block_under_nodes(struct memory_block *mem_blk) kobject_name(&node_devices[mem_blk->nid]->dev.kobj)); } -int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn) +int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, + enum meminit_context context) { - return walk_memory_range(start_pfn, end_pfn, (void *)&nid, - register_mem_sect_under_node); + walk_memory_blocks_func_t func; + + if (context == MEMINIT_HOTPLUG) + func = register_mem_block_under_node_hotplug; + else + func = register_mem_block_under_node_early; + + return walk_memory_range(start_pfn, end_pfn, (void *)&nid, func); } #ifdef CONFIG_HUGETLBFS diff --git a/include/linux/node.h b/include/linux/node.h index 708939bae9aa..a79ec4492650 100644 --- a/include/linux/node.h +++ b/include/linux/node.h @@ -32,11 +32,13 @@ extern struct node *node_devices[]; typedef void (*node_registration_func_t)(struct node *); #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA) -extern int link_mem_sections(int nid, unsigned long start_pfn, - unsigned long end_pfn); +int link_mem_sections(int nid, unsigned long start_pfn, + unsigned long end_pfn, + enum meminit_context context); #else static inline int link_mem_sections(int nid, unsigned long start_pfn, - unsigned long end_pfn) + unsigned long end_pfn, + enum meminit_context context) { return 0; } @@ -61,7 +63,8 @@ static inline int register_one_node(int nid) if (error) return error; /* link memory sections under this node */ - error = link_mem_sections(nid, start_pfn, end_pfn); + error = link_mem_sections(nid, start_pfn, end_pfn, + MEMINIT_EARLY); } return error; diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index c839c4ad4871..e60e28131f67 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1102,7 +1102,8 @@ int __ref add_memory_resource(int nid, struct resource *res, bool online) } /* link memory sections under this node.*/ - ret = link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1)); + ret = link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1), + MEMINIT_HOTPLUG); BUG_ON(ret); /* create new memmap entry */