linux-stable/mm
Huang Ying 89b0387708 mm, swap: fix swapoff with KSM pages
commit 7af7a8e19f upstream.

KSM pages may be mapped to the multiple VMAs that cannot be reached from
one anon_vma.  So during swapin, a new copy of the page need to be
generated if a different anon_vma is needed, please refer to comments of
ksm_might_need_to_copy() for details.

During swapoff, unuse_vma() uses anon_vma (if available) to locate VMA and
virtual address mapped to the page, so not all mappings to a swapped out
KSM page could be found.  So in try_to_unuse(), even if the swap count of
a swap entry isn't zero, the page needs to be deleted from swap cache, so
that, in the next round a new page could be allocated and swapin for the
other mappings of the swapped out KSM page.

But this contradicts with the THP swap support.  Where the THP could be
deleted from swap cache only after the swap count of every swap entry in
the huge swap cluster backing the THP has reach 0.  So try_to_unuse() is
changed in commit e07098294a ("mm, THP, swap: support to reclaim swap
space for THP swapped out") to check that before delete a page from swap
cache, but this has broken KSM swapoff too.

Fortunately, KSM is for the normal pages only, so the original behavior
for KSM pages could be restored easily via checking PageTransCompound().
That is how this patch works.

The bug is introduced by e07098294a ("mm, THP, swap: support to reclaim
swap space for THP swapped out"), which is merged by v4.14-rc1.  So I
think we should backport the fix to from 4.14 on.  But Hugh thinks it may
be rare for the KSM pages being in the swap device when swapoff, so nobody
reports the bug so far.

Link: http://lkml.kernel.org/r/20181226051522.28442-1-ying.huang@intel.com
Fixes: e07098294a ("mm, THP, swap: support to reclaim swap space for THP swapped out")
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reported-by: Hugh Dickins <hughd@google.com>
Tested-by: Hugh Dickins <hughd@google.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-13 10:01:02 +01:00
..
kasan kasan: fix shadow_size calculation error in kasan_module_alloc 2018-08-24 13:09:12 +02:00
backing-dev.c bdi: Fix another oops in wb_workfn() 2018-07-22 14:28:49 +02:00
balloon_compaction.c virtio_balloon: fix deadlock on OOM 2018-10-13 09:27:30 +02:00
bootmem.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cleancache.c fs: switch ->s_uuid to uuid_t 2017-06-05 16:59:12 +02:00
cma.c mm/cma.c: take __GFP_NOWARN into account in cma_alloc() 2017-10-13 16:18:32 -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 License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compaction.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debug.c mm: get rid of vmacache_flush_all() entirely 2018-09-19 22:43:48 +02:00
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 lib/vsprintf.c: remove %Z support 2017-02-27 18:43:47 -08:00
early_ioremap.c mm/early_ioremap: Fix boot hang with earlyprintk=efi,keep 2018-02-25 11:08:03 +01:00
fadvise.c mm/fadvise.c: fix signed overflow UBSAN complaint 2018-09-15 09:45:28 +02:00
failslab.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
filemap.c mm/filemap.c: fix NULL pointer in page_cache_tree_insert() 2018-04-24 09:36:39 +02:00
frame_vector.c mm/frame_vector.c: release a semaphore in 'get_vaddr_frames()' 2018-03-03 10:24:21 +01:00
frontswap.c mm, frontswap: convert frontswap_enabled to static key 2016-07-26 16:19:19 -07:00
gup.c mm: do not bug_on on incorrect length in __mm_populate() 2018-07-17 11:39:29 +02:00
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: mark hmm_devmem_{add, add_resource} EXPORT_SYMBOL_GPL 2019-01-13 10:01:02 +01:00
huge_memory.c mm/huge_memory: fix lockdep complaint on 32-bit i_size_read() 2018-12-05 19:41:08 +01:00
hugetlb.c userfaultfd: use ENOENT instead of EFAULT if the atomic copy user fails 2018-12-08 13:03:37 +01:00
hugetlb_cgroup.c
hwpoison-inject.c mm: hwpoison: call shake_page() unconditionally 2017-05-03 15:52:12 -07:00
init-mm.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
internal.h mm, oom: do not rely on TIF_MEMDIE for memory reserves access 2017-09-06 17:27:30 -07:00
interval_tree.c lib/interval_tree: fast overlap detection 2017-09-08 18:26:49 -07:00
Kconfig mm: don't allow deferred pages with NEED_PER_CPU_KM 2018-05-22 18:53:58 +02:00
Kconfig.debug kmemcheck: rip it out 2018-02-22 15:42:24 +01:00
khugepaged.c mm/khugepaged: collapse_shmem() do not crash on Compound 2018-12-05 19:41:09 +01:00
kmemleak-test.c
kmemleak.c mm/kmemleak.c: wait for scan completion before disabling free 2018-05-30 07:52:21 +02:00
ksm.c mm/ksm.c: ignore STABLE_FLAG of rmap_item->address in rmap_walk_ksm() 2018-07-03 11:25:03 +02:00
list_lru.c mm: memcontrol: use vmalloc fallback for large kmem memcg arrays 2017-10-03 17:54:25 -07:00
maccess.c x86: remove more uaccess_32.h complexity 2016-05-22 17:21:27 -07:00
madvise.c mm: madvise(MADV_DODUMP): allow hugetlbfs pages 2018-10-10 08:54:22 +02:00
Makefile kmemcheck: rip it out 2018-02-22 15:42:24 +01:00
memblock.c Revert "mm: page_alloc: skip over regions of invalid pfns where possible" 2018-03-28 18:24:39 +02:00
memcontrol.c memcg: remove memcg_cgroup::id from IDR on mem_cgroup_css_alloc() failure 2018-09-05 09:26:32 +02:00
memory-failure.c mm: hwpoison: disable memory error handling on 1GB hugepage 2018-07-11 16:29:20 +02:00
memory.c mm/memory.c: recheck page table entry with page table lock held 2018-12-01 09:42:51 +01:00
memory_hotplug.c hwpoison, memory_hotplug: allow hwpoisoned pages to be offlined 2019-01-13 10:01:02 +01:00
mempolicy.c mm: thp: relax __GFP_THISNODE for MADV_HUGEPAGE mappings 2018-11-21 09:24:09 +01:00
mempool.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
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 mm, thp: fix mlocking THP page with migration enabled 2018-10-13 09:27:22 +02:00
mincore.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mlock.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mm_init.c
mmap.c mm: do not bug_on on incorrect length in __mm_populate() 2018-07-17 11:39:29 +02:00
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_notifier.c mm/mmu_notifier: kill invalidate_page 2017-08-31 16:13:00 -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 2018-08-15 18:12:51 +02:00
mremap.c mremap: properly flush TLB before releasing the page 2018-10-20 09:48:53 +02:00
msync.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nobootmem.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 Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:13:32 -07:00
oom_kill.c mm, oom: fix concurrent munlock and oom reaper unmap, v3 2018-05-16 10:10:27 +02:00
page-writeback.c writeback: safer lock nesting 2018-04-24 09:36:39 +02:00
page_alloc.c mm/page_alloc.c: fix calculation of pgdat->nr_zones 2018-12-17 09:28:54 +01:00
page_counter.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_ext.c mm/page_ext.c: check if page_ext is not prepared 2017-11-24 08:37:05 +01:00
page_idle.c mm: thp: fix potential clearing to referenced flag in page_idle_clear_pte_refs_one() 2018-05-30 07:52:24 +02:00
page_io.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_isolation.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_owner.c mm/page_owner: fix recursion bug after changing skip entries 2018-05-30 07:52:21 +02:00
page_poison.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_vma_mapped.c mm/rmap: map_pte() was not handling private ZONE_DEVICE page properly 2018-11-13 11:15:08 -08:00
pagewalk.c mm/pagewalk.c: report holes in hugetlb ranges 2017-11-24 08:37:04 +01:00
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: add __GFP_NORETRY semantics to the percpu balancing path 2018-04-08 14:26:29 +02:00
percpu-stats.c percpu: fix starting offset for chunk statistics traversal 2017-09-27 14:45:57 -07:00
percpu-vm.c percpu: add __GFP_NORETRY semantics to the percpu balancing path 2018-04-08 14:26:29 +02:00
percpu.c percpu: stop leaking bitmap metadata blocks 2018-10-18 09:16:23 +02:00
pgtable-generic.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
process_vm_access.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/mm.h> 2017-03-02 08:42:28 +01:00
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 readahead: stricter check for bdi io_pages 2018-09-09 19:55:53 +02:00
rmap.c mm: migration: fix migration of huge PMD shared pages 2018-10-13 09:27:22 +02:00
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 userfaultfd: shmem: UFFDIO_COPY: set the page dirty if VM_WRITE is not set 2018-12-08 13:03:37 +01:00
slab.c mm: don't warn about large allocations for slab 2018-12-01 09:42:51 +01:00
slab.h kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK 2018-02-22 15:42:23 +01:00
slab_common.c mm: don't warn about large allocations for slab 2018-12-01 09:42:51 +01:00
slob.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
slub.c slub: make ->cpu_partial unsigned int 2018-10-03 17:00:55 -07:00
sparse-vmemmap.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sparse.c mm: sections are not offlined during memory hotremove 2018-05-16 10:10:27 +02:00
swap.c mm: avoid marking swap cached page as lazyfree 2017-10-03 17:54:24 -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 License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
swap_state.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
swapfile.c mm, swap: fix swapoff with KSM pages 2019-01-13 10:01:02 +01:00
truncate.c mm: cleancache: fix corruption on missed inode invalidation 2018-12-08 13:03:40 +01:00
usercopy.c mm/usercopy: Drop extra is_vmalloc_or_module() check 2017-04-05 12:30:18 -07:00
userfaultfd.c userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas 2018-12-08 13:03:38 +01:00
util.c mm: treat indirectly reclaimable memory as free in overcommit logic 2018-10-18 09:16:25 +02:00
vmacache.c mm: get rid of vmacache_flush_all() entirely 2018-09-19 22:43:48 +02:00
vmalloc.c mm: vmalloc: avoid racy handling of debugobjects in vunmap 2018-08-03 07:50:23 +02:00
vmpressure.c mm, vmpressure: pass-through notification support 2017-07-10 16:32:31 -07:00
vmscan.c mm: don't miss the last page because of round-off error 2018-12-29 13:39:11 +01:00
vmstat.c mm: hide incomplete nr_indirectly_reclaimable in /proc/zoneinfo 2018-12-08 13:03:40 +01:00
workingset.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
z3fold.c z3fold: fix possible reclaim races 2018-12-01 09:42:54 +01:00
zbud.c
zpool.c
zsmalloc.c zsmalloc: calling zs_map_object() from irq is a bug 2017-12-14 09:53:10 +01:00
zswap.c zswap: re-check zswap_is_full() after do zswap_shrink() 2018-09-05 09:26:30 +02:00