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Michal Hocko 9d7899999c mm, memory_hotplug: check zone_movable in has_unmovable_pages
Page state checks are racy.  Under a heavy memory workload (e.g.  stress
-m 200 -t 2h) it is quite easy to hit a race window when the page is
allocated but its state is not fully populated yet.  A debugging patch to
dump the struct page state shows

  has_unmovable_pages: pfn:0x10dfec00, found:0x1, count:0x0
  page:ffffea0437fb0000 count:1 mapcount:1 mapping:ffff880e05239841 index:0x7f26e5000 compound_mapcount: 1
  flags: 0x5fffffc0090034(uptodate|lru|active|head|swapbacked)

Note that the state has been checked for both PageLRU and PageSwapBacked
already.  Closing this race completely would require some sort of retry
logic.  This can be tricky and error prone (think of potential endless
or long taking loops).

Workaround this problem for movable zones at least.  Such a zone should
only contain movable pages.  Commit 15c30bc090 ("mm, memory_hotplug:
make has_unmovable_pages more robust") has told us that this is not
strictly true though.  Bootmem pages should be marked reserved though so
we can move the original check after the PageReserved check.  Pages from
other zones are still prone to races but we even do not pretend that
memory hotremove works for those so pre-mature failure doesn't hurt that
much.

Link: http://lkml.kernel.org/r/20181106095524.14629-1-mhocko@kernel.org
Fixes: 15c30bc090 ("mm, memory_hotplug: make has_unmovable_pages more robust")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Baoquan He <bhe@redhat.com>
Tested-by: Baoquan He <bhe@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-11-18 10:15:09 -08:00
..
kasan mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
Kconfig mm: remove CONFIG_HAVE_MEMBLOCK 2018-10-31 08:54:15 -07:00
Kconfig.debug mm: clarify CONFIG_PAGE_POISONING and usage 2018-08-22 10:52:44 -07:00
Makefile mm: remove nobootmem 2018-10-31 08:54:16 -07:00
backing-dev.c blkcg: delay blkg destruction until after writeback has finished 2018-08-31 14:48:56 -06:00
balloon_compaction.c virtio_balloon: fix deadlock on OOM 2017-11-14 23:57:38 +02:00
cleancache.c mm: use octal not symbolic permissions 2018-06-15 07:55:25 +09:00
cma.c mm/cma: remove unsupported gfp_mask parameter from cma_alloc() 2018-08-17 16:20:32 -07:00
cma.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cma_debug.c mm/cma: remove unsupported gfp_mask parameter from cma_alloc() 2018-08-17 16:20:32 -07:00
compaction.c psi: pressure stall information for CPU, memory, and IO 2018-10-26 16:26:32 -07:00
debug.c mm: provide kernel parameter to allow disabling page init poisoning 2018-10-26 16:26:34 -07:00
debug_page_ref.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dmapool.c mm: use octal not symbolic permissions 2018-06-15 07:55:25 +09:00
early_ioremap.c mm/early_ioremap: Fix boot hang with earlyprintk=efi,keep 2017-12-11 14:54:44 +01:00
fadvise.c vfs: implement readahead(2) using POSIX_FADV_WILLNEED 2018-08-30 20:01:32 +02:00
failslab.c mm: use octal not symbolic permissions 2018-06-15 07:55:25 +09:00
filemap.c vfs: rework data cloning infrastructure 2018-11-02 09:33:08 -07:00
frame_vector.c mm/frame_vector.c: release a semaphore in 'get_vaddr_frames()' 2017-12-14 16:00:48 -08:00
frontswap.c mm: use octal not symbolic permissions 2018-06-15 07:55:25 +09:00
gup.c mm/gup.c: fix __get_user_pages_fast() comment 2018-10-31 08:54:17 -07:00
gup_benchmark.c mm/gup_benchmark.c: prevent integer overflow in ioctl 2018-10-31 08:54:12 -07:00
highmem.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hmm.c mm/hmm: invalidate device page table at start of invalidation 2018-10-31 08:54:12 -07:00
huge_memory.c mm, thp: consolidate THP gfp handling into alloc_hugepage_direct_gfpmask 2018-11-03 10:09:37 -07:00
hugetlb.c hugetlbfs: fix kernel BUG at fs/hugetlbfs/inode.c:444! 2018-11-18 10:15:09 -08:00
hugetlb_cgroup.c mm: rename page_counter's count/limit into usage/max 2018-06-07 17:34:35 -07:00
hwpoison-inject.c mm/memory_failure: Remove unused trapno from memory_failure 2018-01-23 12:17:42 -06:00
init-mm.c mm: Allocate the mm_cpumask (mm->cpu_bitmap[]) dynamically based on nr_cpu_ids 2018-07-17 09:35:30 +02:00
internal.h memblock: rename __free_pages_bootmem to memblock_free_pages 2018-10-31 08:54:16 -07:00
interval_tree.c mm/interval_tree.c: use vma_pages() helper 2018-01-31 17:18:37 -08:00
khugepaged.c mm: Convert khugepaged_scan_shmem to XArray 2018-10-21 10:46:38 -04:00
kmemleak-test.c mm: convert printk(KERN_<LEVEL> to pr_<level> 2016-03-17 15:09:34 -07:00
kmemleak.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
ksm.c include/linux/compiler*.h: make compiler-*.h mutually exclusive 2018-08-22 17:31:34 -07:00
list_lru.c mm/list_lru: introduce list_lru_shrink_walk_irq() 2018-08-17 16:20:32 -07:00
maccess.c x86/fault: BUG() when uaccess helpers fault on kernel addresses 2018-09-03 15:12:09 +02:00
madvise.c Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
memblock.c mm/memblock.c: warn if zero alignment was requested 2018-10-31 08:54:17 -07:00
memcontrol.c mm: handle no memcg case in memcg_kmem_charge() properly 2018-11-03 10:09:37 -07:00
memfd.c memfd: Convert memfd_tag_pins to XArray 2018-10-21 10:46:41 -04:00
memory-failure.c libnvdimm-for-4.19_dax-memory-failure 2018-08-25 18:43:59 -07:00
memory.c mm: Fix warning in insert_pfn() 2018-10-31 08:54:17 -07:00
memory_hotplug.c memory_hotplug: cond_resched in __remove_pages 2018-11-03 10:09:38 -07:00
mempolicy.c mm, thp: consolidate THP gfp handling into alloc_hugepage_direct_gfpmask 2018-11-03 10:09:37 -07:00
mempool.c mm/mempool.c: add missing parameter description 2018-08-22 10:52:44 -07:00
memtest.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
migrate.c Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
mincore.c xarray: Replace exceptional entries 2018-09-29 22:47:49 -04:00
mlock.c dax: remove VM_MIXEDMAP for fsdax and device dax 2018-08-17 16:20:27 -07:00
mm_init.c mm: access zone->node via zone_to_nid() and zone_set_nid() 2018-08-22 10:52:45 -07:00
mmap.c mm: brk: downgrade mmap_sem to read when shrinking 2018-10-26 16:26:35 -07:00
mmu_context.c sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h> 2017-03-02 08:42:38 +01:00
mmu_gather.c mm/memory: Move mmu_gather and TLB invalidation code into its own file 2018-09-07 15:19:25 +01:00
mmu_notifier.c Revert "mm, mmu_notifier: annotate mmu notifiers with blockable invalidate callbacks" 2018-10-26 16:25:19 -07:00
mmzone.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mprotect.c x86/speculation/l1tf: Disallow non privileged high MMIO PROT_NONE mappings 2018-06-20 19:10:01 +02:00
mremap.c mm: mremap: downgrade mmap_sem to read when shrinking 2018-10-26 16:26:35 -07:00
msync.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nommu.c mm/gup: cache dev_pagemap while pinning pages 2018-10-26 16:38:15 -07:00
oom_kill.c Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-10-24 11:22:39 +01:00
page-writeback.c Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
page_alloc.c mm, memory_hotplug: check zone_movable in has_unmovable_pages 2018-11-18 10:15:09 -08:00
page_counter.c memcg: introduce memory.min 2018-06-07 17:34:36 -07:00
page_ext.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
page_idle.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
page_io.c for-linus-20181102 2018-11-02 11:25:48 -07:00
page_isolation.c mm, migrate: remove reason argument from new_page_t 2018-04-11 10:28:32 -07:00
page_owner.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
page_poison.c virtio, vhost: fixes, tweaks 2018-11-01 14:42:49 -07:00
page_vma_mapped.c mm/rmap: map_pte() was not handling private ZONE_DEVICE page properly 2018-10-31 08:54:11 -07:00
pagewalk.c mm: kernel-doc: add missing parameter descriptions 2018-04-05 21:36:27 -07:00
percpu-internal.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
percpu-km.c percpu: allow select gfp to be passed to underlying allocators 2018-02-18 05:33:01 -08:00
percpu-stats.c treewide: Use array_size() in vmalloc() 2018-06-12 16:19:22 -07:00
percpu-vm.c percpu: allow select gfp to be passed to underlying allocators 2018-02-18 05:33:01 -08:00
percpu.c Merge branch 'for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu 2018-11-01 09:27:57 -07:00
pgtable-generic.c x86/mm: Page size aware flush_tlb_mm_range() 2018-10-09 16:51:11 +02:00
process_vm_access.c mm: docs: add blank lines to silence sphinx "Unexpected indentation" errors 2018-02-06 18:32:48 -08:00
quicklist.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
readahead.c mm: Convert __do_page_cache_readahead to XArray 2018-10-21 10:46:37 -04:00
rmap.c mm: migration: fix migration of huge PMD shared pages 2018-10-05 16:32:04 -07:00
rodata_test.c mm: fix RODATA_TEST failure "rodata_test: test data was not read only" 2017-10-03 17:54:24 -07:00
shmem.c mm, thp: consolidate THP gfp handling into alloc_hugepage_direct_gfpmask 2018-11-03 10:09:37 -07:00
slab.c mm, slab: combine kmalloc_caches and kmalloc_dma_caches 2018-10-26 16:26:31 -07:00
slab.h mm: introduce CONFIG_MEMCG_KMEM as combination of CONFIG_MEMCG && !CONFIG_SLOB 2018-08-17 16:20:30 -07:00
slab_common.c mm, slab: shorten kmalloc cache names for large sizes 2018-10-26 16:26:32 -07:00
slob.c slab: __GFP_ZERO is incompatible with a constructor 2018-06-07 17:34:34 -07:00
slub.c mm, slab: combine kmalloc_caches and kmalloc_dma_caches 2018-10-26 16:26:31 -07:00
sparse-vmemmap.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
sparse.c memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
swap.c Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
swap_cgroup.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
swap_slots.c mm, swap, get_swap_pages: use entry_size instead of cluster in parameter 2018-08-22 10:52:44 -07:00
swap_state.c Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
swapfile.c mm/swapfile.c: use kvzalloc for swap_info_struct allocation 2018-11-18 10:15:09 -08:00
truncate.c mm: Convert truncate to XArray 2018-10-21 10:46:37 -04:00
usercopy.c usercopy: Allow boot cmdline disabling of hardening 2018-07-04 08:04:52 -07:00
userfaultfd.c userfaultfd: prevent non-cooperative events vs mcopy_atomic races 2018-06-07 17:34:38 -07:00
util.c kvfree(): fix misleading comment 2018-10-26 16:26:33 -07:00
vmacache.c mm: get rid of vmacache_flush_all() entirely 2018-09-13 15:18:04 -10:00
vmalloc.c vfree: add debug might_sleep() 2018-10-26 16:26:33 -07:00
vmpressure.c mm/vmpressure.c: convert to use match_string() helper 2018-06-07 17:34:36 -07:00
vmscan.c Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
vmstat.c mm/vmstat.c: assert that vmstat_text is in sync with stat_items_size 2018-10-26 16:26:35 -07:00
workingset.c Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
z3fold.c z3fold: fix possible reclaim races 2018-11-18 10:15:09 -08:00
zbud.c mm: docs: fix parameter names mismatch 2018-02-06 18:32:48 -08:00
zpool.c mm/zpool.c: zpool_evictable: fix mismatch in parameter name and kernel-doc 2018-02-21 15:35:43 -08:00
zsmalloc.c mm/zsmalloc.c: fix fall-through annotation 2018-10-26 16:26:35 -07:00
zswap.c zswap: re-check zswap_is_full() after do zswap_shrink() 2018-07-26 19:38:03 -07:00