WSL2-Linux-Kernel/mm
Hugh Dickins b7c35587be memfd: fix F_SEAL_WRITE after shmem huge page allocated
commit f2b277c4d1 upstream.

Wangyong reports: after enabling tmpfs filesystem to support transparent
hugepage with the following command:

  echo always > /sys/kernel/mm/transparent_hugepage/shmem_enabled

the docker program tries to add F_SEAL_WRITE through the following
command, but it fails unexpectedly with errno EBUSY:

  fcntl(5, F_ADD_SEALS, F_SEAL_WRITE) = -1.

That is because memfd_tag_pins() and memfd_wait_for_pins() were never
updated for shmem huge pages: checking page_mapcount() against
page_count() is hopeless on THP subpages - they need to check
total_mapcount() against page_count() on THP heads only.

Make memfd_tag_pins() (compared > 1) as strict as memfd_wait_for_pins()
(compared != 1): either can be justified, but given the non-atomic
total_mapcount() calculation, it is better now to be strict.  Bear in
mind that total_mapcount() itself scans all of the THP subpages, when
choosing to take an XA_CHECK_SCHED latency break.

Also fix the unlikely xa_is_value() case in memfd_wait_for_pins(): if a
page has been swapped out since memfd_tag_pins(), then its refcount must
have fallen, and so it can safely be untagged.

Link: https://lkml.kernel.org/r/a4f79248-df75-2c8c-3df-ba3317ccb5da@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Zeal Robot <zealci@zte.com.cn>
Reported-by: wangyong <wang.yong12@zte.com.cn>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: CGEL ZTE <cgel.zte@gmail.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yang Yang <yang.yang29@zte.com.cn>
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>
2022-03-08 19:12:48 +01:00
..
damon mm/damon/dbgfs: fix 'struct pid' leaks in 'dbgfs_target_ids_write()' 2022-01-05 12:42:39 +01:00
kasan kasan: fix quarantine conflicting with init_on_free 2022-03-08 19:12:38 +01:00
kfence kfence: fix memory leak when cat kfence objects 2021-12-29 12:29:00 +01:00
Kconfig kmap_local: don't assume kmap PTEs are linear arrays in memory 2021-11-25 09:48:43 +01:00
Kconfig.debug
Makefile mm: introduce Data Access MONitor (DAMON) 2021-09-08 11:50:24 -07:00
backing-dev.c mm: bdi: initialize bdi_min_ratio when bdi is unregistered 2021-12-14 10:57:11 +01:00
balloon_compaction.c
bootmem_info.c mm/bootmem_info.c: mark __init on register_page_bootmem_info_section 2021-09-03 09:58:14 -07:00
cleancache.c
cma.c
cma.h
cma_debug.c
cma_sysfs.c
compaction.c Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
debug.c mm/debug: sync up latest migrate_reason to migrate_reason_names 2021-09-24 16:13:35 -07:00
debug_page_ref.c
debug_vm_pgtable.c mm/debug_vm_pgtable: remove pte entry from the page table 2022-02-08 18:34:05 +01:00
dmapool.c
early_ioremap.c mm/early_ioremap.c: remove redundant early_ioremap_shutdown() 2021-09-08 11:50:24 -07:00
fadvise.c
failslab.c
filemap.c mm/filemap: Fix handling of THPs in generic_file_buffered_read() 2022-03-02 11:47:47 +01:00
frontswap.c
gup.c Revert "mm/gup: small refactoring: simplify try_grab_page()" 2022-02-05 12:38:57 +01:00
gup_test.c
gup_test.h
highmem.c kmap_local: don't assume kmap PTEs are linear arrays in memory 2021-11-25 09:48:43 +01:00
hmm.c mm/hmm.c: allow VM_MIXEDMAP to work with hmm_range_fault 2022-01-27 11:05:43 +01:00
huge_memory.c mm: filemap: check if THP has hwpoisoned subpage for PMD page fault 2021-10-28 17:18:55 -07:00
hugetlb.c hugetlbfs: flush TLBs correctly after huge_pmd_unshare 2021-11-25 09:49:07 +01:00
hugetlb_cgroup.c
hugetlb_vmemmap.c
hugetlb_vmemmap.h
hwpoison-inject.c mm: hwpoison: don't drop slab caches for offlining non-LRU page 2021-09-03 09:58:15 -07:00
init-mm.c
internal.h mm/numa: automatically generate node migration order 2021-09-03 09:58:16 -07:00
interval_tree.c
io-mapping.c
ioremap.c mm: move ioremap_page_range to vmalloc.c 2021-09-08 11:50:24 -07:00
khugepaged.c mm: khugepaged: skip huge page collapse for special files 2021-10-28 17:18:55 -07:00
kmemleak.c mm/kmemleak: avoid scanning potential huge holes 2022-02-08 18:34:05 +01:00
ksm.c mm/ksm: remove old GCC 4.9+ check 2021-09-13 10:18:28 -07:00
list_lru.c
maccess.c
madvise.c Merge branch 'akpm' (patches from Andrew) 2021-09-03 10:08:28 -07:00
mapping_dirty_helpers.c
memblock.c memblock: use kfree() to release kmalloced memblock regions 2022-03-02 11:48:10 +01:00
memcontrol.c mm: memcg: synchronize objcg lists with a dedicated spinlock 2022-02-16 12:56:38 +01:00
memfd.c memfd: fix F_SEAL_WRITE after shmem huge page allocated 2022-03-08 19:12:48 +01:00
memory-failure.c mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page() 2021-12-29 12:28:58 +01:00
memory.c mm: filemap: check if THP has hwpoisoned subpage for PMD page fault 2021-10-28 17:18:55 -07:00
memory_hotplug.c Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
mempolicy.c mm: mempolicy: fix THP allocations escaping mempolicy restrictions 2021-12-29 12:28:58 +01:00
mempool.c
memremap.c mm/memory_hotplug: remove nid parameter from arch_remove_memory() 2021-09-08 11:50:23 -07:00
memtest.c
migrate.c mm/migrate: fix CPUHP state to update node demotion order 2021-10-18 20:22:03 -10:00
mincore.c
mlock.c
mm_init.c
mmap.c Merge tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linux 2021-09-04 11:35:47 -07:00
mmap_lock.c
mmu_gather.c
mmu_notifier.c
mmzone.c
mprotect.c mm: don't try to NUMA-migrate COW pages that have other uses 2022-02-23 12:03:03 +01:00
mremap.c mm/mremap: fix memory account on do_munmap() failure 2021-09-03 09:58:14 -07:00
msync.c
nommu.c Merge tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linux 2021-09-04 11:35:47 -07:00
oom_kill.c mm, oom: do not trigger out_of_memory from the #PF 2021-11-18 19:17:16 +01:00
page-writeback.c Merge branch 'akpm' (patches from Andrew) 2021-09-03 10:08:28 -07:00
page_alloc.c mm/page_alloc.c: do not warn allocation failure on zone DMA if no managed pages 2022-01-27 11:03:00 +01:00
page_counter.c
page_ext.c mm/migrate: add CPU hotplug to demotion #ifdef 2021-10-18 20:22:02 -10:00
page_idle.c mm/idle_page_tracking: make PG_idle reusable 2021-09-08 11:50:24 -07:00
page_io.c
page_isolation.c Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
page_owner.c mm: remove pfn_valid_within() and CONFIG_HOLES_IN_ZONE 2021-09-08 11:50:22 -07:00
page_poison.c
page_reporting.c
page_reporting.h
page_vma_mapped.c
pagewalk.c
percpu-internal.h
percpu-km.c
percpu-stats.c
percpu-vm.c
percpu.c Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
pgalloc-track.h
pgtable-generic.c
process_vm_access.c
ptdump.c
readahead.c
rmap.c Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
rodata_test.c
secretmem.c mm/secretmem: avoid letting secretmem_users drop to zero 2021-10-28 17:18:55 -07:00
shmem.c shmem: fix a race between shmem_unused_huge_shrink and shmem_evict_inode 2022-01-27 11:03:01 +01:00
shuffle.c
shuffle.h
slab.c mm/migrate: add CPU hotplug to demotion #ifdef 2021-10-18 20:22:02 -10:00
slab.h mm: kmemleak: slob: respect SLAB_NOLEAKTRACE flag 2021-11-25 09:48:42 +01:00
slab_common.c mm: slub: move flush_cpu_slab() invocations __free_slab() invocations out of IRQ context 2021-09-04 01:12:23 +02:00
slob.c
slub.c mm/slub: fix endianness bug for alloc/free_traces attributes 2021-12-14 10:57:11 +01:00
sparse-vmemmap.c
sparse.c mm: introduce memmap_alloc() to unify memory map allocation 2021-09-03 09:58:15 -07:00
swap.c mm: fs: invalidate bh_lrus for only cold path 2021-09-24 16:13:35 -07:00
swap_cgroup.c
swap_slots.c
swap_state.c
swapfile.c mm, memcg: inline swap-related functions to improve disabled memcg config 2021-09-03 09:58:12 -07:00
truncate.c Merge branch 'akpm' (patches from Andrew) 2021-09-03 10:08:28 -07:00
usercopy.c
userfaultfd.c userfaultfd: change mmap_changing to atomic 2021-09-03 09:58:16 -07:00
util.c mm: Consider __GFP_NOWARN flag for oversized kvmalloc() calls 2022-03-08 19:12:44 +01:00
vmacache.c
vmalloc.c mm: defer kmemleak object creation of module_alloc() 2022-03-08 19:12:38 +01:00
vmpressure.c mm/vmpressure: replace vmpressure_to_css() with vmpressure_to_memcg() 2021-09-03 09:58:17 -07:00
vmscan.c mm,vmscan: fix divide by zero in get_scan_count 2021-09-08 18:45:53 -07:00
vmstat.c mm/vmstat: protect per cpu variables with preempt disable on RT 2021-09-08 15:32:34 -07:00
workingset.c memcg: flush lruvec stats in the refault 2021-09-23 10:09:13 -07:00
z3fold.c
zbud.c
zpool.c
zsmalloc.c mm/zsmalloc.c: close race window between zs_pool_dec_isolated() and zs_unregister_migration() 2021-11-18 19:17:10 +01:00
zswap.c