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2020-10-13mm/memory_hotplug: introduce default phys_to_target_node() implementationDan Williams
In preparation to set a fallback value for dev_dax->target_node, introduce generic fallback helpers for phys_to_target_node() A generic implementation based on node-data or memblock was proposed, but as noted by Mike: "Here again, I would prefer to add a weak default for phys_to_target_node() because the "generic" implementation is not really generic. The fallback to reserved ranges is x86 specfic because on x86 most of the reserved areas is not in memblock.memory. AFAIK, no other architecture does this." The info message in the generic memory_add_physaddr_to_nid() implementation is fixed up to properly reflect that memory_add_physaddr_to_nid() communicates "online" node info and phys_to_target_node() indicates "target / to-be-onlined" node info. [akpm@linux-foundation.org: fix CONFIG_MEMORY_HOTPLUG=n build] Link: https://lkml.kernel.org/r/202008252130.7YrHIyMI%25lkp@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: David Hildenbrand <david@redhat.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Jia He <justin.he@arm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brice Goglin <Brice.Goglin@inria.fr> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: David Airlie <airlied@linux.ie> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Hulk Robot <hulkci@huawei.com> Cc: Jason Yan <yanaijie@huawei.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: kernel test robot <lkp@intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Link: https://lkml.kernel.org/r/159643097768.4062302.3135192588966888630.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-26mm: don't rely on system state to detect hot-plug operationsLaurent Dufour
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 <ldufour@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: Scott Cheloha <cheloha@linux.ibm.com> Cc: Tony Luck <tony.luck@intel.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20200915094143.79181-3-ldufour@linux.ibm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-26mm: replace memmap_context by meminit_contextLaurent Dufour
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 <david@redhat.com> Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J . Wysocki" <rafael@kernel.org> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: Scott Cheloha <cheloha@linux.ibm.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: <stable@vger.kernel.org> 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 <torvalds@linux-foundation.org>
2020-09-19mm/memory_hotplug: drain per-cpu pages again during memory offlinePavel Tatashin
There is a race during page offline that can lead to infinite loop: a page never ends up on a buddy list and __offline_pages() keeps retrying infinitely or until a termination signal is received. Thread#1 - a new process: load_elf_binary begin_new_exec exec_mmap mmput exit_mmap tlb_finish_mmu tlb_flush_mmu release_pages free_unref_page_list free_unref_page_prepare set_pcppage_migratetype(page, migratetype); // Set page->index migration type below MIGRATE_PCPTYPES Thread#2 - hot-removes memory __offline_pages start_isolate_page_range set_migratetype_isolate set_pageblock_migratetype(page, MIGRATE_ISOLATE); Set migration type to MIGRATE_ISOLATE-> set drain_all_pages(zone); // drain per-cpu page lists to buddy allocator. Thread#1 - continue free_unref_page_commit migratetype = get_pcppage_migratetype(page); // get old migration type list_add(&page->lru, &pcp->lists[migratetype]); // add new page to already drained pcp list Thread#2 Never drains pcp again, and therefore gets stuck in the loop. The fix is to try to drain per-cpu lists again after check_pages_isolated_cb() fails. Fixes: c52e75935f8d ("mm: remove extra drain pages on pcp list") Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20200903140032.380431-1-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20200904151448.100489-2-pasha.tatashin@soleen.com Link: http://lkml.kernel.org/r/20200904070235.GA15277@dhcp22.suse.cz Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-14mm: replace hpage_nr_pages with thp_nr_pagesMatthew Wilcox (Oracle)
The thp prefix is more frequently used than hpage and we should be consistent between the various functions. [akpm@linux-foundation.org: fix mm/migrate.c] Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: David Hildenbrand <david@redhat.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Link: http://lkml.kernel.org/r/20200629151959.15779-6-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12mm/migrate: introduce a standard migration target allocation functionJoonsoo Kim
There are some similar functions for migration target allocation. Since there is no fundamental difference, it's better to keep just one rather than keeping all variants. This patch implements base migration target allocation function. In the following patches, variants will be converted to use this function. Changes should be mechanical, but, unfortunately, there are some differences. First, some callers' nodemask is assgined to NULL since NULL nodemask will be considered as all available nodes, that is, &node_states[N_MEMORY]. Second, for hugetlb page allocation, gfp_mask is redefined as regular hugetlb allocation gfp_mask plus __GFP_THISNODE if user provided gfp_mask has it. This is because future caller of this function requires to set this node constaint. Lastly, if provided nodeid is NUMA_NO_NODE, nodeid is set up to the node where migration source lives. It helps to remove simple wrappers for setting up the nodeid. Note that PageHighmem() call in previous function is changed to open-code "is_highmem_idx()" since it provides more readability. [akpm@linux-foundation.org: tweak patch title, per Vlastimil] [akpm@linux-foundation.org: fix typo in comment] Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Roman Gushchin <guro@fb.com> Link: http://lkml.kernel.org/r/1594622517-20681-6-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12mm, memory_hotplug: update pcp lists everytime onlining a memory blockCharan Teja Reddy
When onlining a first memory block in a zone, pcp lists are not updated thus pcp struct will have the default setting of ->high = 0,->batch = 1. This means till the second memory block in a zone(if it have) is onlined the pcp lists of this zone will not contain any pages because pcp's ->count is always greater than ->high thus free_pcppages_bulk() is called to free batch size(=1) pages every time system wants to add a page to the pcp list through free_unref_page(). To put this in a word, system is not using benefits offered by the pcp lists when there is a single onlineable memory block in a zone. Correct this by always updating the pcp lists when memory block is onlined. Fixes: 1f522509c77a ("mem-hotplug: avoid multiple zones sharing same boot strapping boot_pageset") Signed-off-by: Charan Teja Reddy <charante@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Vinayak Menon <vinmenon@codeaurora.org> Link: http://lkml.kernel.org/r/1596372896-15336-1-git-send-email-charante@codeaurora.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12mm/memory_hotplug: fix unpaired mem_hotplug_begin/doneJia He
When check_memblock_offlined_cb() returns failed rc(e.g. the memblock is online at that time), mem_hotplug_begin/done is unpaired in such case. Therefore a warning: Call Trace: percpu_up_write+0x33/0x40 try_remove_memory+0x66/0x120 ? _cond_resched+0x19/0x30 remove_memory+0x2b/0x40 dev_dax_kmem_remove+0x36/0x72 [kmem] device_release_driver_internal+0xf0/0x1c0 device_release_driver+0x12/0x20 bus_remove_device+0xe1/0x150 device_del+0x17b/0x3e0 unregister_dev_dax+0x29/0x60 devm_action_release+0x15/0x20 release_nodes+0x19a/0x1e0 devres_release_all+0x3f/0x50 device_release_driver_internal+0x100/0x1c0 driver_detach+0x4c/0x8f bus_remove_driver+0x5c/0xd0 driver_unregister+0x31/0x50 dax_pmem_exit+0x10/0xfe0 [dax_pmem] Fixes: f1037ec0cc8a ("mm/memory_hotplug: fix remove_memory() lockdep splat") Signed-off-by: Jia He <justin.he@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Cc: <stable@vger.kernel.org> [5.6+] Cc: Andy Lutomirski <luto@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chuhong Yuan <hslester96@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Cameron <Jonathan.Cameron@Huawei.com> Cc: Kaly Xin <Kaly.Xin@arm.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200710031619.18762-3-justin.he@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12mm/memory_hotplug: introduce default dummy memory_add_physaddr_to_nid()Jia He
This is to introduce a general dummy helper. memory_add_physaddr_to_nid() is a fallback option to get the nid in case NUMA_NO_NID is detected. After this patch, arm64/sh/s390 can simply use the general dummy version. PowerPC/x86/ia64 will still use their specific version. This is the preparation to set a fallback value for dev_dax->target_node. Signed-off-by: Jia He <justin.he@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chuhong Yuan <hslester96@gmail.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Jonathan Cameron <Jonathan.Cameron@Huawei.com> Cc: Kaly Xin <Kaly.Xin@arm.com> Link: http://lkml.kernel.org/r/20200710031619.18762-2-justin.he@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07mm/memory_hotplug: document why shuffle_zone() is relevantDavid Hildenbrand
It's not completely obvious why we have to shuffle the complete zone - introduced in commit e900a918b098 ("mm: shuffle initial free memory to improve memory-side-cache utilization") - because some sort of shuffling is already performed when onlining pages via __free_one_page(), placing MAX_ORDER-1 pages either to the head or the tail of the freelist. Let's document why we have to shuffle the complete zone when exposing larger, contiguous physical memory areas to the buddy. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Michal Hocko <mhocko@suse.com> Link: http://lkml.kernel.org/r/20200624094741.9918-3-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07mm: remove vm_total_pagesDavid Hildenbrand
The global variable "vm_total_pages" is a relic from older days. There is only a single user that reads the variable - build_all_zonelists() - and the first thing it does is update it. Use a local variable in build_all_zonelists() instead and remove the global variable. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Minchan Kim <minchan@kernel.org> Link: http://lkml.kernel.org/r/20200619132410.23859-2-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-26mm/memory_hotplug.c: fix false softlockup during pfn range removalBen Widawsky
When working with very large nodes, poisoning the struct pages (for which there will be very many) can take a very long time. If the system is using voluntary preemptions, the software watchdog will not be able to detect forward progress. This patch addresses this issue by offering to give up time like __remove_pages() does. This behavior was introduced in v5.6 with: commit d33695b16a9f ("mm/memory_hotplug: poison memmap in remove_pfn_range_from_zone()") Alternately, init_page_poison could do this cond_resched(), but it seems to me that the caller of init_page_poison() is what actually knows whether or not it should relax its own priority. Based on Dan's notes, I think this is perfectly safe: commit f931ab479dd2 ("mm: fix devm_memremap_pages crash, use mem_hotplug_{begin, done}") Aside from fixing the lockup, it is also a friendlier thing to do on lower core systems that might wipe out large chunks of hotplug memory (probably not a very common case). Fixes this kind of splat: watchdog: BUG: soft lockup - CPU#46 stuck for 22s! [daxctl:9922] irq event stamp: 138450 hardirqs last enabled at (138449): [<ffffffffa1001f26>] trace_hardirqs_on_thunk+0x1a/0x1c hardirqs last disabled at (138450): [<ffffffffa1001f42>] trace_hardirqs_off_thunk+0x1a/0x1c softirqs last enabled at (138448): [<ffffffffa1e00347>] __do_softirq+0x347/0x456 softirqs last disabled at (138443): [<ffffffffa10c416d>] irq_exit+0x7d/0xb0 CPU: 46 PID: 9922 Comm: daxctl Not tainted 5.7.0-BEN-14238-g373c6049b336 #30 Hardware name: Intel Corporation PURLEY/PURLEY, BIOS PLYXCRB1.86B.0578.D07.1902280810 02/28/2019 RIP: 0010:memset_erms+0x9/0x10 Code: c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 Call Trace: remove_pfn_range_from_zone+0x3a/0x380 memunmap_pages+0x17f/0x280 release_nodes+0x22a/0x260 __device_release_driver+0x172/0x220 device_driver_detach+0x3e/0xa0 unbind_store+0x113/0x130 kernfs_fop_write+0xdc/0x1c0 vfs_write+0xde/0x1d0 ksys_write+0x58/0xd0 do_syscall_64+0x5a/0x120 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Built 2 zonelists, mobility grouping on. Total pages: 49050381 Policy zone: Normal Built 3 zonelists, mobility grouping on. Total pages: 49312525 Policy zone: Normal David said: "It really only is an issue for devmem. Ordinary hotplugged system memory is not affected (onlined/offlined in memory block granularity)." Link: http://lkml.kernel.org/r/20200619231213.1160351-1-ben.widawsky@intel.com Fixes: commit d33695b16a9f ("mm/memory_hotplug: poison memmap in remove_pfn_range_from_zone()") Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: "Scargall, Steve" <steve.scargall@intel.com> Reported-by: Ben Widawsky <ben.widawsky@intel.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-10Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio updates from Michael Tsirkin: - virtio-mem: paravirtualized memory hotplug - support doorbell mapping for vdpa - config interrupt support in ifc - fixes all over the place * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (40 commits) vhost/test: fix up after API change virtio_mem: convert device block size into 64bit virtio-mem: drop unnecessary initialization ifcvf: implement config interrupt in IFCVF vhost: replace -1 with VHOST_FILE_UNBIND in ioctls vhost_vdpa: Support config interrupt in vdpa ifcvf: ignore continuous setting same status value virtio-mem: Don't rely on implicit compiler padding for requests virtio-mem: Try to unplug the complete online memory block first virtio-mem: Use -ETXTBSY as error code if the device is busy virtio-mem: Unplug subblocks right-to-left virtio-mem: Drop manual check for already present memory virtio-mem: Add parent resource for all added "System RAM" virtio-mem: Better retry handling virtio-mem: Offline and remove completely unplugged memory blocks mm/memory_hotplug: Introduce offline_and_remove_memory() virtio-mem: Allow to offline partially unplugged memory blocks mm: Allow to offline unmovable PageOffline() pages via MEM_GOING_OFFLINE virtio-mem: Paravirtualized memory hotunplug part 2 virtio-mem: Paravirtualized memory hotunplug part 1 ...
2020-06-04mm/memory_hotplug: fix a typo in comment "recoreded"->"recorded"Ethon Paul
There is a typo in comment, fix it. s/recoreded/recorded Signed-off-by: Ethon Paul <ethp@qq.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Ralph Campbell <rcampbell@nvidia.com> Link: http://lkml.kernel.org/r/20200410160328.13843-1-ethp@qq.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04mm/memory_hotplug: introduce add_memory_driver_managed()David Hildenbrand
Patch series "mm/memory_hotplug: Interface to add driver-managed system ram", v4. kexec (via kexec_load()) can currently not properly handle memory added via dax/kmem, and will have similar issues with virtio-mem. kexec-tools will currently add all memory to the fixed-up initial firmware memmap. In case of dax/kmem, this means that - in contrast to a proper reboot - how that persistent memory will be used can no longer be configured by the kexec'd kernel. In case of virtio-mem it will be harmful, because that memory might contain inaccessible pieces that require coordination with hypervisor first. In both cases, we want to let the driver in the kexec'd kernel handle detecting and adding the memory, like during an ordinary reboot. Introduce add_memory_driver_managed(). More on the samentics are in patch #1. In the future, we might want to make this behavior configurable for dax/kmem- either by configuring it in the kernel (which would then also allow to configure kexec_file_load()) or in kexec-tools by also adding "System RAM (kmem)" memory from /proc/iomem to the fixed-up initial firmware memmap. More on the motivation can be found in [1] and [2]. [1] https://lkml.kernel.org/r/20200429160803.109056-1-david@redhat.com [2] https://lkml.kernel.org/r/20200430102908.10107-1-david@redhat.com This patch (of 3): Some device drivers rely on memory they managed to not get added to the initial (firmware) memmap as system RAM - so it's not used as initial system RAM by the kernel and the driver is under control. While this is the case during cold boot and after a reboot, kexec is not aware of that and might add such memory to the initial (firmware) memmap of the kexec kernel. We need ways to teach kernel and userspace that this system ram is different. For example, dax/kmem allows to decide at runtime if persistent memory is to be used as system ram. Another future user is virtio-mem, which has to coordinate with its hypervisor to deal with inaccessible parts within memory resources. We want to let users in the kernel (esp. kexec) but also user space (esp. kexec-tools) know that this memory has different semantics and needs to be handled differently: 1. Don't create entries in /sys/firmware/memmap/ 2. Name the memory resource "System RAM ($DRIVER)" (exposed via /proc/iomem) ($DRIVER might be "kmem", "virtio_mem"). 3. Flag the memory resource IORESOURCE_MEM_DRIVER_MANAGED /sys/firmware/memmap/ [1] represents the "raw firmware-provided memory map" because "on most architectures that firmware-provided memory map is modified afterwards by the kernel itself". The primary user is kexec on x86-64. Since commit d96ae5309165 ("memory-hotplug: create /sys/firmware/memmap entry for new memory"), we add all hotplugged memory to that firmware memmap - which makes perfect sense for traditional memory hotplug on x86-64, where real HW will also add hotplugged DIMMs to the firmware memmap. We replicate what the "raw firmware-provided memory map" looks like after hot(un)plug. To keep things simple, let the user provide the full resource name instead of only the driver name - this way, we don't have to manually allocate/craft strings for memory resources. Also use the resource name to make decisions, to avoid passing additional flags. In case the name isn't "System RAM", it's special. We don't have to worry about firmware_map_remove() on the removal path. If there is no entry, it will simply return with -EINVAL. We'll adapt dax/kmem in a follow-up patch. [1] https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-firmware-memmap Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Baoquan He <bhe@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Dan Williams <dan.j.williams@intel.com> Link: http://lkml.kernel.org/r/20200508084217.9160-1-david@redhat.com Link: http://lkml.kernel.org/r/20200508084217.9160-3-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04mm/memory_hotplug: handle memblocks only with CONFIG_ARCH_KEEP_MEMBLOCKDavid Hildenbrand
The comment in add_memory_resource() is stale: hotadd_new_pgdat() will no longer call get_pfn_range_for_nid(), as a hotadded pgdat will simply span no pages at all, until memory is moved to the zone/node via move_pfn_range_to_zone() - e.g., when onlining memory blocks. The only archs that care about memblocks for hotplugged memory (either for iterating over all system RAM or testing for memory validity) are arm64, s390x, and powerpc - due to CONFIG_ARCH_KEEP_MEMBLOCK. Without CONFIG_ARCH_KEEP_MEMBLOCK, we can simply stop messing with memblocks. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Link: http://lkml.kernel.org/r/20200422155353.25381-3-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04mm/memory_hotplug: set node_start_pfn of hotadded pgdat to 0David Hildenbrand
Patch series "mm/memory_hotplug: handle memblocks only with CONFIG_ARCH_KEEP_MEMBLOCK", v1. A hotadded node/pgdat will span no pages at all, until memory is moved to the zone/node via move_pfn_range_to_zone() -> resize_pgdat_range - e.g., when onlining memory blocks. We don't have to initialize the node_start_pfn to the memory we are adding. This patch (of 2): Especially, there is an inconsistency: - Hotplugging memory to a memory-less node with cpus: node_start_pf == 0 - Offlining and removing last memory from a node: node_start_pfn == 0 - Hotplugging memory to a memory-less node without cpus: node_start_pfn != 0 As soon as memory is onlined, node_start_pfn is overwritten with the actual start. E.g., when adding two DIMMs but only onlining one of both, only that DIMM (with online memory blocks) is spanned by the node. Currently, the validity of node_start_pfn really is linked to node_spanned_pages != 0. With node_spanned_pages == 0 (e.g., before onlining memory), it has no meaning. So let's stop setting node_start_pfn, just to be overwritten via move_pfn_range_to_zone(). This avoids confusion when looking at the code, wondering which magic will be performed with the node_start_pfn in this function, when hotadding a pgdat. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Michal Hocko <mhocko@suse.com> Link: http://lkml.kernel.org/r/20200422155353.25381-1-david@redhat.com Link: http://lkml.kernel.org/r/20200422155353.25381-2-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04mm/memory_hotplug: remove is_mem_section_removable()David Hildenbrand
Fortunately, all users of is_mem_section_removable() are gone. Get rid of it, including some now unnecessary functions. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Baoquan He <bhe@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Oscar Salvador <osalvador@suse.de> Link: http://lkml.kernel.org/r/20200407135416.24093-3-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04mm/memory_hotplug: refrain from adding memory into an impossible nodeVishal Verma
A misbehaving qemu created a situation where the ACPI SRAT table advertised one fewer proximity domains than intended. The NFIT table did describe all the expected proximity domains. This caused the device dax driver to assign an impossible target_node to the device, and when hotplugged as system memory, this would fail with the following signature: BUG: kernel NULL pointer dereference, address: 0000000000000088 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 80000001767d4067 P4D 80000001767d4067 PUD 10e0c4067 PMD 0 Oops: 0000 [#1] SMP PTI CPU: 4 PID: 22737 Comm: kswapd3 Tainted: G O 5.6.0-rc5 #9 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:prepare_kswapd_sleep+0x7c/0xc0 Code: 89 df e8 87 fd ff ff 89 c2 31 c0 84 d2 74 e6 0f 1f 44 00 00 48 8b 05 fb af 7a 01 48 63 93 88 1d 01 00 48 8b 84 d0 20 0f 00 00 <48> 3b 98 88 00 00 00 75 28 f0 80 a0 80 00 00 00 fe f0 80 a3 38 20 RSP: 0018:ffffc900017a3e78 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff8881209e0000 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffff8881209e0e80 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000008000 R10: 0000000000000000 R11: 0000000000000003 R12: 0000000000000003 R13: 0000000000000003 R14: 0000000000000000 R15: ffffc900017a3ec8 FS: 0000000000000000(0000) GS:ffff888318c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000088 CR3: 0000000120b50002 CR4: 00000000001606e0 Call Trace: kswapd+0x103/0x520 kthread+0x120/0x140 ret_from_fork+0x3a/0x50 Add a check in the add_memory path to fail if the node to which we are adding memory is in the node_possible_map Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: David Hildenbrand <david@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Link: http://lkml.kernel.org/r/20200416225438.15208-1-vishal.l.verma@intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04mm/memory_hotplug: Introduce offline_and_remove_memory()David Hildenbrand
virtio-mem wants to offline and remove a memory block once it unplugged all subblocks (e.g., using alloc_contig_range()). Let's provide an interface to do that from a driver. virtio-mem already supports to offline partially unplugged memory blocks. Offlining a fully unplugged memory block will not require to migrate any pages. All unplugged subblocks are PageOffline() and have a reference count of 0 - so offlining code will simply skip them. All we need is an interface to offline and remove the memory from kernel module context, where we don't have access to the memory block devices (esp. find_memory_block() and device_offline()) and the device hotplug lock. To keep things simple, allow to only work on a single memory block. Acked-by: Michal Hocko <mhocko@suse.com> Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David Hildenbrand <david@redhat.com> Cc: Oscar Salvador <osalvador@suse.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Qian Cai <cai@lca.pw> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-9-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04mm: Allow to offline unmovable PageOffline() pages via MEM_GOING_OFFLINEDavid Hildenbrand
virtio-mem wants to allow to offline memory blocks of which some parts were unplugged (allocated via alloc_contig_range()), especially, to later offline and remove completely unplugged memory blocks. The important part is that PageOffline() has to remain set until the section is offline, so these pages will never get accessed (e.g., when dumping). The pages should not be handed back to the buddy (which would require clearing PageOffline() and result in issues if offlining fails and the pages are suddenly in the buddy). Let's allow to do that by allowing to isolate any PageOffline() page when offlining. This way, we can reach the memory hotplug notifier MEM_GOING_OFFLINE, where the driver can signal that he is fine with offlining this page by dropping its reference count. PageOffline() pages with a reference count of 0 can then be skipped when offlining the pages (like if they were free, however they are not in the buddy). Anybody who uses PageOffline() pages and does not agree to offline them (e.g., Hyper-V balloon, XEN balloon, VMWare balloon for 2MB pages) will not decrement the reference count and make offlining fail when trying to migrate such an unmovable page. So there should be no observable change. Same applies to balloon compaction users (movable PageOffline() pages), the pages will simply be migrated. Note 1: If offlining fails, a driver has to increment the reference count again in MEM_CANCEL_OFFLINE. Note 2: A driver that makes use of this has to be aware that re-onlining the memory block has to be handled by hooking into onlining code (online_page_callback_t), resetting the page PageOffline() and not giving them to the buddy. Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Pavel Tatashin <pavel.tatashin@microsoft.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Anthony Yznaga <anthony.yznaga@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Qian Cai <cai@lca.pw> Cc: Pingfan Liu <kernelfans@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-7-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-03mm/page_alloc: integrate classzone_idx and high_zoneidxJoonsoo Kim
classzone_idx is just different name for high_zoneidx now. So, integrate them and add some comment to struct alloc_context in order to reduce future confusion about the meaning of this variable. The accessor, ac_classzone_idx() is also removed since it isn't needed after integration. In addition to integration, this patch also renames high_zoneidx to highest_zoneidx since it represents more precise meaning. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Ye Xiaolong <xiaolong.ye@intel.com> Link: http://lkml.kernel.org/r/1587095923-7515-3-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03mm: remove CONFIG_HAVE_MEMBLOCK_NODE_MAP optionMike Rapoport
CONFIG_HAVE_MEMBLOCK_NODE_MAP is used to differentiate initialization of nodes and zones structures between the systems that have region to node mapping in memblock and those that don't. Currently all the NUMA architectures enable this option and for the non-NUMA systems we can presume that all the memory belongs to node 0 and therefore the compile time configuration option is not required. The remaining few architectures that use DISCONTIGMEM without NUMA are easily updated to use memblock_add_node() instead of memblock_add() and thus have proper correspondence of memblock regions to NUMA nodes. Still, free_area_init_node() must have a backward compatible version because its semantics with and without CONFIG_HAVE_MEMBLOCK_NODE_MAP is different. Once all the architectures will use the new semantics, the entire compatibility layer can be dropped. To avoid addition of extra run time memory to store node id for architectures that keep memblock but have only a single node, the node id field of the memblock_region is guarded by CONFIG_NEED_MULTIPLE_NODES and the corresponding accessors presume that in those cases it is always 0. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Hoan Tran <hoan@os.amperecomputing.com> [arm64] Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64] Cc: Baoquan He <bhe@redhat.com> Cc: Brian Cain <bcain@codeaurora.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200412194859.12663-4-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10mm/memory_hotplug: add pgprot_t to mhp_paramsLogan Gunthorpe
devm_memremap_pages() is currently used by the PCI P2PDMA code to create struct page mappings for IO memory. At present, these mappings are created with PAGE_KERNEL which implies setting the PAT bits to be WB. However, on x86, an mtrr register will typically override this and force the cache type to be UC-. In the case firmware doesn't set this register it is effectively WB and will typically result in a machine check exception when it's accessed. Other arches are not currently likely to function correctly seeing they don't have any MTRR registers to fall back on. To solve this, provide a way to specify the pgprot value explicitly to arch_add_memory(). Of the arches that support MEMORY_HOTPLUG: x86_64, and arm64 need a simple change to pass the pgprot_t down to their respective functions which set up the page tables. For x86_32, set the page tables explicitly using _set_memory_prot() (seeing they are already mapped). For ia64, s390 and sh, reject anything but PAGE_KERNEL settings -- this should be fine, for now, seeing these architectures don't support ZONE_DEVICE. A check in __add_pages() is also added to ensure the pgprot parameter was set for all arches. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Badger <ebadger@gigaio.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200306170846.9333-7-logang@deltatee.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10mm/memory_hotplug: rename mhp_restrictions to mhp_paramsLogan Gunthorpe
The mhp_restrictions struct really doesn't specify anything resembling a restriction anymore so rename it to be mhp_params as it is a list of extended parameters. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Badger <ebadger@gigaio.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200306170846.9333-3-logang@deltatee.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm/memory_hotplug.c: use __pfn_to_section() instead of open-codingchenqiwu
Use __pfn_to_section() API instead of open-coding for better code readability. Signed-off-by: chenqiwu <chenqiwu@xiaomi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Hildenbrand <david@redhat.com> Link: http://lkml.kernel.org/r/1584345134-16671-1-git-send-email-qiwuchen55@gmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm/memory_hotplug: allow to specify a default online_typeDavid Hildenbrand
For now, distributions implement advanced udev rules to essentially - Don't online any hotplugged memory (s390x) - Online all memory to ZONE_NORMAL (e.g., most virt environments like hyperv) - Online all memory to ZONE_MOVABLE in case the zone imbalance is taken care of (e.g., bare metal, special virt environments) In summary: All memory is usually onlined the same way, however, the kernel always has to ask user space to come up with the same answer. E.g., Hyper-V always waits for a memory block to get onlined before continuing, otherwise it might end up adding memory faster than onlining it, which can result in strange OOM situations. This waiting slows down adding of a bigger amount of memory. Let's allow to specify a default online_type, not just "online" and "offline". This allows distributions to configure the default online_type when booting up and be done with it. We can now specify "offline", "online", "online_movable" and "online_kernel" via - "memhp_default_state=" on the kernel cmdline - /sys/devices/system/memory/auto_online_blocks just like we are able to specify for a single memory block via /sys/devices/system/memory/memoryX/state Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Baoquan He <bhe@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Yumei Huang <yuhuang@redhat.com> Link: http://lkml.kernel.org/r/20200317104942.11178-9-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm/memory_hotplug: convert memhp_auto_online to store an online_typeDavid Hildenbrand
... and rename it to memhp_default_online_type. This is a preparation for more detailed default online behavior. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Baoquan He <bhe@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Yumei Huang <yuhuang@redhat.com> Link: http://lkml.kernel.org/r/20200317104942.11178-8-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm/memory_hotplug: unexport memhp_auto_onlineDavid Hildenbrand
All in-tree users except the mm-core are gone. Let's drop the export. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Baoquan He <bhe@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Yumei Huang <yuhuang@redhat.com> Link: http://lkml.kernel.org/r/20200317104942.11178-7-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm/memory_hotplug.c: cleanup __add_pages()David Hildenbrand
Let's drop the basically unused section stuff and simplify. The logic now matches the logic in __remove_pages(). Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Cc: Segher Boessenkool <segher@kernel.crashing.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Link: http://lkml.kernel.org/r/20200228095819.10750-3-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm/memory_hotplug.c: simplify calculation of number of pages in __remove_pages()David Hildenbrand
In commit 52fb87c81f11 ("mm/memory_hotplug: cleanup __remove_pages()"), we cleaned up __remove_pages(), and introduced a shorter variant to calculate the number of pages to the next section boundary. Turns out we can make this calculation easier to read. We always want to have the number of pages (> 0) to the next section boundary, starting from the current pfn. We'll clean up __remove_pages() in a follow-up patch and directly make use of this computation. Suggested-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Link: http://lkml.kernel.org/r/20200228095819.10750-2-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm/memory_hotplug.c: only respect mem= parameter during boot stageBaoquan He
In commit 357b4da50a62 ("x86: respect memory size limiting via mem= parameter") a global varialbe max_mem_size is added to store the value parsed from 'mem= ', then checked when memory region is added. This truly stops those DIMMs from being added into system memory during boot-time. However, it also limits the later memory hotplug functionality. Any DIMM can't be hotplugged any more if its region is beyond the max_mem_size. We will get errors like: [ 216.387164] acpi PNP0C80:02: add_memory failed [ 216.389301] acpi PNP0C80:02: acpi_memory_enable_device() error [ 216.392187] acpi PNP0C80:02: Enumeration failure This will cause issue in a known use case where 'mem=' is added to the hypervisor. The memory that lies after 'mem=' boundary will be assigned to KVM guests. After commit 357b4da50a62 merged, memory can't be extended dynamically if system memory on hypervisor is not sufficient. So fix it by also checking if it's during boot-time restricting to add memory. Otherwise, skip the restriction. And also add this use case to document of 'mem=' kernel parameter. Fixes: 357b4da50a62 ("x86: respect memory size limiting via mem= parameter") Signed-off-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: William Kucharski <william.kucharski@oracle.com> Cc: David Hildenbrand <david@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com> Link: http://lkml.kernel.org/r/20200204050643.20925-1-bhe@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm: code cleanup for MADV_FREEHuang Ying
Some comments for MADV_FREE is revised and added to help people understand the MADV_FREE code, especially the page flag, PG_swapbacked. This makes page_is_file_cache() isn't consistent with its comments. So the function is renamed to page_is_file_lru() to make them consistent again. All these are put in one patch as one logical change. Suggested-by: David Hildenbrand <david@redhat.com> Suggested-by: Johannes Weiner <hannes@cmpxchg.org> Suggested-by: David Rientjes <rientjes@google.com> Signed-off-by: "Huang, Ying" <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@kernel.org> Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Rik van Riel <riel@surriel.com> Link: http://lkml.kernel.org/r/20200317100342.2730705-1-ying.huang@intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-06mm, hotplug: fix page online with DEBUG_PAGEALLOC compiled but not enabledVlastimil Babka
Commit cd02cf1aceea ("mm/hotplug: fix an imbalance with DEBUG_PAGEALLOC") fixed memory hotplug with debug_pagealloc enabled, where onlining a page goes through page freeing, which removes the direct mapping. Some arches don't like when the page is not mapped in the first place, so generic_online_page() maps it first. This is somewhat wasteful, but better than special casing page freeing fast paths. The commit however missed that DEBUG_PAGEALLOC configured doesn't mean it's actually enabled. One has to test debug_pagealloc_enabled() since 031bc5743f15 ("mm/debug-pagealloc: make debug-pagealloc boottime configurable"), or alternatively debug_pagealloc_enabled_static() since 8e57f8acbbd1 ("mm, debug_pagealloc: don't rely on static keys too early"), but this is not done. As a result, a s390 kernel with DEBUG_PAGEALLOC configured but not enabled will crash: Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 0000000000000000 TEID: 0000000000000483 Fault in home space mode while using kernel ASCE. AS:0000001ece13400b R2:000003fff7fd000b R3:000003fff7fcc007 S:000003fff7fd7000 P:000000000000013d Oops: 0004 ilc:2 [#1] SMP CPU: 1 PID: 26015 Comm: chmem Kdump: loaded Tainted: GX 5.3.18-5-default #1 SLE15-SP2 (unreleased) Krnl PSW : 0704e00180000000 0000001ecd281b9e (__kernel_map_pages+0x166/0x188) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000000 0000000000000800 0000400b00000000 0000000000000100 0000000000000001 0000000000000000 0000000000000002 0000000000000100 0000001ece139230 0000001ecdd98d40 0000400b00000100 0000000000000000 000003ffa17e4000 001fffe0114f7d08 0000001ecd4d93ea 001fffe0114f7b20 Krnl Code: 0000001ecd281b8e: ec17ffff00d8 ahik %r1,%r7,-1 0000001ecd281b94: ec111dbc0355 risbg %r1,%r1,29,188,3 >0000001ecd281b9e: 94fb5006 ni 6(%r5),251 0000001ecd281ba2: 41505008 la %r5,8(%r5) 0000001ecd281ba6: ec51fffc6064 cgrj %r5,%r1,6,1ecd281b9e 0000001ecd281bac: 1a07 ar %r0,%r7 0000001ecd281bae: ec03ff584076 crj %r0,%r3,4,1ecd281a5e Call Trace: [<0000001ecd281b9e>] __kernel_map_pages+0x166/0x188 [<0000001ecd4d9516>] online_pages_range+0xf6/0x128 [<0000001ecd2a8186>] walk_system_ram_range+0x7e/0xd8 [<0000001ecda28aae>] online_pages+0x2fe/0x3f0 [<0000001ecd7d02a6>] memory_subsys_online+0x8e/0xc0 [<0000001ecd7add42>] device_online+0x5a/0xc8 [<0000001ecd7d0430>] state_store+0x88/0x118 [<0000001ecd5b9f62>] kernfs_fop_write+0xc2/0x200 [<0000001ecd5064b6>] vfs_write+0x176/0x1e0 [<0000001ecd50676a>] ksys_write+0xa2/0x100 [<0000001ecda315d4>] system_call+0xd8/0x2c8 Fix this by checking debug_pagealloc_enabled_static() before calling kernel_map_pages(). Backports for kernel before 5.5 should use debug_pagealloc_enabled() instead. Also add comments. Fixes: cd02cf1aceea ("mm/hotplug: fix an imbalance with DEBUG_PAGEALLOC") Reported-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: <stable@vger.kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Qian Cai <cai@lca.pw> Link: http://lkml.kernel.org/r/20200224094651.18257-1-vbabka@suse.cz Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04mm/memory_hotplug: drop valid_start/valid_end from test_pages_in_a_zone()David Hildenbrand
The callers are only interested in the actual zone, they don't care about boundaries. Return the zone instead to simplify. Link: http://lkml.kernel.org/r/20200110183308.11849-1-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04mm/memory_hotplug: cleanup __remove_pages()David Hildenbrand
Let's drop the basically unused section stuff and simplify. Also, let's use a shorter variant to calculate the number of pages to the next section boundary. Link: http://lkml.kernel.org/r/20191006085646.5768-11-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Pankaj Gupta <pagupta@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04mm/memory_hotplug: drop local variables in shrink_zone_span()David Hildenbrand
Get rid of the unnecessary local variables. Link: http://lkml.kernel.org/r/20191006085646.5768-10-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pankaj Gupta <pagupta@redhat.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04mm/memory_hotplug: don't check for "all holes" in shrink_zone_span()David Hildenbrand
If we have holes, the holes will automatically get detected and removed once we remove the next bigger/smaller section. The extra checks can go. Link: http://lkml.kernel.org/r/20191006085646.5768-9-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pankaj Gupta <pagupta@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04mm/memory_hotplug: we always have a zone in find_(smallest|biggest)_section_pfnDavid Hildenbrand
With shrink_pgdat_span() out of the way, we now always have a valid zone. Link: http://lkml.kernel.org/r/20191006085646.5768-8-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pankaj Gupta <pagupta@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04mm/memory_hotplug: poison memmap in remove_pfn_range_from_zone()David Hildenbrand
Let's poison the pages similar to when adding new memory in sparse_add_section(). Also call remove_pfn_range_from_zone() from memunmap_pages(), so we can poison the memmap from there as well. Link: http://lkml.kernel.org/r/20191006085646.5768-7-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pankaj Gupta <pagupta@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-31mm/memory_hotplug: pass in nid to online_pages()David Hildenbrand
Patch series "mm/memory_hotplug: pass in nid to online_pages()". Simplify onlining code and get rid of find_memory_block(). Pass in the nid from the memory block we are trying to online directly, instead of manually looking it up. This patch (of 2): No need to lookup the memory block, we can directly pass in the nid. Link: http://lkml.kernel.org/r/20200113113354.6341-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-31mm: remove "count" parameter from has_unmovable_pages()David Hildenbrand
Now that the memory isolate notifier is gone, the parameter is always 0. Drop it and cleanup has_unmovable_pages(). Link: http://lkml.kernel.org/r/20191114131911.11783-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Qian Cai <cai@lca.pw> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Alexander Potapenko <glider@google.com> Cc: Arun KS <arunks@codeaurora.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-31mm/memory_hotplug: fix remove_memory() lockdep splatDan Williams
The daxctl unit test for the dax_kmem driver currently triggers the (false positive) lockdep splat below. It results from the fact that remove_memory_block_devices() is invoked under the mem_hotplug_lock() causing lockdep entanglements with cpu_hotplug_lock() and sysfs (kernfs active state tracking). It is a false positive because the sysfs attribute path triggering the memory remove is not the same attribute path associated with memory-block device. sysfs_break_active_protection() is not applicable since there is no real deadlock conflict, instead move memory-block device removal outside the lock. The mem_hotplug_lock() is not needed to synchronize the memory-block device removal vs the page online state, that is already handled by lock_device_hotplug(). Specifically, lock_device_hotplug() is sufficient to allow try_remove_memory() to check the offline state of the memblocks and be assured that any in progress online attempts are flushed / blocked by kernfs_drain() / attribute removal. The add_memory() path safely creates memblock devices under the mem_hotplug_lock(). There is no kernfs active state synchronization in the memblock device_register() path, so nothing to fix there. This change is only possible thanks to the recent change that refactored memory block device removal out of arch_remove_memory() (commit 4c4b7f9ba948 "mm/memory_hotplug: remove memory block devices before arch_remove_memory()"), and David's due diligence tracking down the guarantees afforded by kernfs_drain(). Not flagged for -stable since this only impacts ongoing development and lockdep validation, not a runtime issue. ====================================================== WARNING: possible circular locking dependency detected 5.5.0-rc3+ #230 Tainted: G OE ------------------------------------------------------ lt-daxctl/6459 is trying to acquire lock: ffff99c7f0003510 (kn->count#241){++++}, at: kernfs_remove_by_name_ns+0x41/0x80 but task is already holding lock: ffffffffa76a5450 (mem_hotplug_lock.rw_sem){++++}, at: percpu_down_write+0x20/0xe0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (mem_hotplug_lock.rw_sem){++++}: __lock_acquire+0x39c/0x790 lock_acquire+0xa2/0x1b0 get_online_mems+0x3e/0xb0 kmem_cache_create_usercopy+0x2e/0x260 kmem_cache_create+0x12/0x20 ptlock_cache_init+0x20/0x28 start_kernel+0x243/0x547 secondary_startup_64+0xb6/0xc0 -> #1 (cpu_hotplug_lock.rw_sem){++++}: __lock_acquire+0x39c/0x790 lock_acquire+0xa2/0x1b0 cpus_read_lock+0x3e/0xb0 online_pages+0x37/0x300 memory_subsys_online+0x17d/0x1c0 device_online+0x60/0x80 state_store+0x65/0xd0 kernfs_fop_write+0xcf/0x1c0 vfs_write+0xdb/0x1d0 ksys_write+0x65/0xe0 do_syscall_64+0x5c/0xa0 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (kn->count#241){++++}: check_prev_add+0x98/0xa40 validate_chain+0x576/0x860 __lock_acquire+0x39c/0x790 lock_acquire+0xa2/0x1b0 __kernfs_remove+0x25f/0x2e0 kernfs_remove_by_name_ns+0x41/0x80 remove_files.isra.0+0x30/0x70 sysfs_remove_group+0x3d/0x80 sysfs_remove_groups+0x29/0x40 device_remove_attrs+0x39/0x70 device_del+0x16a/0x3f0 device_unregister+0x16/0x60 remove_memory_block_devices+0x82/0xb0 try_remove_memory+0xb5/0x130 remove_memory+0x26/0x40 dev_dax_kmem_remove+0x44/0x6a [kmem] device_release_driver_internal+0xe4/0x1c0 unbind_store+0xef/0x120 kernfs_fop_write+0xcf/0x1c0 vfs_write+0xdb/0x1d0 ksys_write+0x65/0xe0 do_syscall_64+0x5c/0xa0 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: kn->count#241 --> cpu_hotplug_lock.rw_sem --> mem_hotplug_lock.rw_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(mem_hotplug_lock.rw_sem); lock(cpu_hotplug_lock.rw_sem); lock(mem_hotplug_lock.rw_sem); lock(kn->count#241); *** DEADLOCK *** No fixes tag as this has been a long standing issue that predated the addition of kernfs lockdep annotations. Link: http://lkml.kernel.org/r/157991441887.2763922.4770790047389427325.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-04mm/memory_hotplug: shrink zones when offlining memoryDavid Hildenbrand
We currently try to shrink a single zone when removing memory. We use the zone of the first page of the memory we are removing. If that memmap was never initialized (e.g., memory was never onlined), we will read garbage and can trigger kernel BUGs (due to a stale pointer): BUG: unable to handle page fault for address: 000000000000353d #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP PTI CPU: 1 PID: 7 Comm: kworker/u8:0 Not tainted 5.3.0-rc5-next-20190820+ #317 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.4 Workqueue: kacpi_hotplug acpi_hotplug_work_fn RIP: 0010:clear_zone_contiguous+0x5/0x10 Code: 48 89 c6 48 89 c3 e8 2a fe ff ff 48 85 c0 75 cf 5b 5d c3 c6 85 fd 05 00 00 01 5b 5d c3 0f 1f 840 RSP: 0018:ffffad2400043c98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000200000000 RCX: 0000000000000000 RDX: 0000000000200000 RSI: 0000000000140000 RDI: 0000000000002f40 RBP: 0000000140000000 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000140000 R13: 0000000000140000 R14: 0000000000002f40 R15: ffff9e3e7aff3680 FS: 0000000000000000(0000) GS:ffff9e3e7bb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000353d CR3: 0000000058610000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __remove_pages+0x4b/0x640 arch_remove_memory+0x63/0x8d try_remove_memory+0xdb/0x130 __remove_memory+0xa/0x11 acpi_memory_device_remove+0x70/0x100 acpi_bus_trim+0x55/0x90 acpi_device_hotplug+0x227/0x3a0 acpi_hotplug_work_fn+0x1a/0x30 process_one_work+0x221/0x550 worker_thread+0x50/0x3b0 kthread+0x105/0x140 ret_from_fork+0x3a/0x50 Modules linked in: CR2: 000000000000353d Instead, shrink the zones when offlining memory or when onlining failed. Introduce and use remove_pfn_range_from_zone(() for that. We now properly shrink the zones, even if we have DIMMs whereby - Some memory blocks fall into no zone (never onlined) - Some memory blocks fall into multiple zones (offlined+re-onlined) - Multiple memory blocks that fall into different zones Drop the zone parameter (with a potential dubious value) from __remove_pages() and __remove_section(). Link: http://lkml.kernel.org/r/20191006085646.5768-6-david@redhat.com Fixes: f1dd2cd13c4b ("mm, memory_hotplug: do not associate hotadded memory to zones until online") [visible after d0dc12e86b319] Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: <stable@vger.kernel.org> [5.0+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-01mm/memory_hotplug.c: remove __online_page_set_limits()Souptick Joarder
__online_page_set_limits() is a dummy function - remove it and all callers. Link: http://lkml.kernel.org/r/8e1bc9d3b492f6bde16e95ebc1dee11d6aefabd7.1567889743.git.jrdr.linux@gmail.com Link: http://lkml.kernel.org/r/854db2cf8145d9635249c95584d9a91fd774a229.1567889743.git.jrdr.linux@gmail.com Link: http://lkml.kernel.org/r/9afe6c5a18158f3884a6b302ac2c772f3da49ccc.1567889743.git.jrdr.linux@gmail.com Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Juergen Gross <jgross@suse.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-01mm/memory_hotplug.c: don't allow to online/offline memory blocks with holesDavid Hildenbrand
Our onlining/offlining code is unnecessarily complicated. Only memory blocks added during boot can have holes (a range that is not IORESOURCE_SYSTEM_RAM). Hotplugged memory never has holes (e.g., see add_memory_resource()). All memory blocks that belong to boot memory are already online. Note that boot memory can have holes and the memmap of the holes is marked PG_reserved. However, also memory allocated early during boot is PG_reserved - basically every page of boot memory that is not given to the buddy is PG_reserved. Therefore, when we stop allowing to offline memory blocks with holes, we implicitly no longer have to deal with onlining memory blocks with holes. E.g., online_pages() will do a walk_system_ram_range(..., online_pages_range), whereby online_pages_range() will effectively only free the memory holes not falling into a hole to the buddy. The other pages (holes) are kept PG_reserved (via move_pfn_range_to_zone()->memmap_init_zone()). This allows to simplify the code. For example, we no longer have to worry about marking pages that fall into memory holes PG_reserved when onlining memory. We can stop setting pages PG_reserved completely in memmap_init_zone(). Offlining memory blocks added during boot is usually not guaranteed to work either way (unmovable data might have easily ended up on that memory during boot). So stopping to do that should not really hurt. Also, people are not even aware of a setup where onlining/offlining of memory blocks with holes used to work reliably (see [1] and [2] especially regarding the hotplug path) - I doubt it worked reliably. For the use case of offlining memory to unplug DIMMs, we should see no change. (holes on DIMMs would be weird). Please note that hardware errors (PG_hwpoison) are not memory holes and are not affected by this change when offlining. [1] https://lkml.org/lkml/2019/10/22/135 [2] https://lkml.org/lkml/2019/8/14/1365 Link: http://lkml.kernel.org/r/20191119115237.6662-1-david@redhat.com Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-01mm/page_isolation.c: convert SKIP_HWPOISON to MEMORY_OFFLINEDavid Hildenbrand
We have two types of users of page isolation: 1. Memory offlining: Offline memory so it can be unplugged. Memory won't be touched. 2. Memory allocation: Allocate memory (e.g., alloc_contig_range()) to become the owner of the memory and make use of it. For example, in case we want to offline memory, we can ignore (skip over) PageHWPoison() pages, as the memory won't get used. We can allow to offline memory. In contrast, we don't want to allow to allocate such memory. Let's generalize the approach so we can special case other types of pages we want to skip over in case we offline memory. While at it, also pass the same flags to test_pages_isolated(). Link: http://lkml.kernel.org/r/20191021172353.3056-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Suggested-by: Michal Hocko <mhocko@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: Qian Cai <cai@lca.pw> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Pavel Tatashin <pavel.tatashin@microsoft.com> Cc: Wei Yang <richard.weiyang@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-01mm/page_alloc.c: don't set pages PageReserved() when offliningDavid Hildenbrand
Patch series "mm: Memory offlining + page isolation cleanups", v2. This patch (of 2): We call __offline_isolated_pages() from __offline_pages() after all pages were isolated and are either free (PageBuddy()) or PageHWPoison. Nothing can stop us from offlining memory at this point. In __offline_isolated_pages() we first set all affected memory sections offline (offline_mem_sections(pfn, end_pfn)), to mark the memmap as invalid (pfn_to_online_page() will no longer succeed), and then walk over all pages to pull the free pages from the free lists (to the isolated free lists, to be precise). Note that re-onlining a memory block will result in the whole memmap getting reinitialized, overwriting any old state. We already poision the memmap when offlining is complete to find any access to stale/uninitialized memmaps. So, setting the pages PageReserved() is not helpful. The memap is marked offline and all pageblocks are isolated. As soon as offline, the memmap is stale either way. This looks like a leftover from ancient times where we initialized the memmap when adding memory and not when onlining it (the pages were set PageReserved so re-onling would work as expected). Link: http://lkml.kernel.org/r/20191021172353.3056-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Oscar Salvador <osalvador@suse.de> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Pavel Tatashin <pavel.tatashin@microsoft.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: Qian Cai <cai@lca.pw> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-01mm/memory_hotplug: remove __online_page_free() and ↵David Hildenbrand
__online_page_increment_counters() Let's drop the now unused functions. Link: http://lkml.kernel.org/r/20190909114830.662-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Qian Cai <cai@lca.pw> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Sasha Levin <sashal@kernel.org> Cc: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-01mm/memory_hotplug: export generic_online_page()David Hildenbrand
Patch series "mm/memory_hotplug: Export generic_online_page()". Let's replace the __online_page...() functions by generic_online_page(). Hyper-V only wants to delay the actual onlining of un-backed pages, so we can simpy re-use the generic function. This patch (of 3): Let's expose generic_online_page() so online_page_callback users can simply fall back to the generic implementation when actually deciding to online the pages. Link: http://lkml.kernel.org/r/20190909114830.662-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Qian Cai <cai@lca.pw> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Sasha Levin <sashal@kernel.org> Cc: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>