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Jia He 83d116c530 mm: fix double page fault on arm64 if PTE_AF is cleared 
When we tested pmdk unit test [1] vmmalloc_fork TEST3 on arm64 guest, there
will be a double page fault in __copy_from_user_inatomic of cow_user_page.

To reproduce the bug, the cmd is as follows after you deployed everything:
make -C src/test/vmmalloc_fork/ TEST_TIME=60m check

Below call trace is from arm64 do_page_fault for debugging purpose:
[  110.016195] Call trace:
[  110.016826]  do_page_fault+0x5a4/0x690
[  110.017812]  do_mem_abort+0x50/0xb0
[  110.018726]  el1_da+0x20/0xc4
[  110.019492]  __arch_copy_from_user+0x180/0x280
[  110.020646]  do_wp_page+0xb0/0x860
[  110.021517]  __handle_mm_fault+0x994/0x1338
[  110.022606]  handle_mm_fault+0xe8/0x180
[  110.023584]  do_page_fault+0x240/0x690
[  110.024535]  do_mem_abort+0x50/0xb0
[  110.025423]  el0_da+0x20/0x24

The pte info before __copy_from_user_inatomic is (PTE_AF is cleared):
[ffff9b007000] pgd=000000023d4f8003, pud=000000023da9b003,
               pmd=000000023d4b3003, pte=360000298607bd3

As told by Catalin: "On arm64 without hardware Access Flag, copying from
user will fail because the pte is old and cannot be marked young. So we
always end up with zeroed page after fork() + CoW for pfn mappings. we
don't always have a hardware-managed access flag on arm64."

This patch fixes it by calling pte_mkyoung. Also, the parameter is
changed because vmf should be passed to cow_user_page()

Add a WARN_ON_ONCE when __copy_from_user_inatomic() returns error
in case there can be some obscure use-case (by Kirill).

[1] https://github.com/pmem/pmdk/tree/master/src/test/vmmalloc_fork

Signed-off-by: Jia He <justin.he@arm.com>
Reported-by: Yibo Cai <Yibo.Cai@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-18 11:11:29 +01:00
..
kasan
mm: introduce compound_nr()
2019-09-24 15:54:08 -07:00
backing-dev.c
bdi: Do not use freezable workqueue
2019-10-06 09:11:35 -06:00
balloon_compaction.c
mm/balloon_compaction: suppress allocation warnings
2019-09-04 07:42:01 -04:00
cleancache.c
Driver Core and debugfs changes for 5.3-rc1
2019-07-12 12:24:03 -07:00
cma_debug.c
mm/cma_debug.c: fix the break condition in cma_maxchunk_get()
2019-05-14 09:47:45 -07:00
cma.c
mm/cma.c: fail if fixed declaration can't be honored
2019-07-16 19:23:21 -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
compaction.c
mm/compaction.c: remove unnecessary zone parameter in isolate_migratepages()
2019-09-24 15:54:10 -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
debug.c
mm: update references to page _refcount
2019-05-14 19:52:47 -07:00
dmapool.c
mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options
2019-07-12 11:05:46 -07:00
early_ioremap.c
mm/early_ioremap: Fix boot hang with earlyprintk=efi,keep
2017-12-11 14:54:44 +01:00
fadvise.c
fs: Export generic_fadvise()
2019-08-30 22:43:58 -07:00
failslab.c
mm/failslab.c: by default, do not fail allocations with direct reclaim only
2019-07-12 11:05:43 -07:00
filemap.c
mm,thp: avoid writes to file with THP in pagecache
2019-09-24 15:54:11 -07:00
frame_vector.c
mm: untag user pointers in get_vaddr_frames
2019-09-25 17:51:41 -07:00
frontswap.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 482
2019-06-19 17:09:52 +02:00
gup_benchmark.c
mm/gup: replace get_user_pages_longterm() with FOLL_LONGTERM
2019-05-14 09:47:45 -07:00
gup.c
mm: untag user pointers in mm/gup.c
2019-09-25 17:51:41 -07:00
highmem.c
mm: convert totalram_pages and totalhigh_pages variables to atomic
2018-12-28 12:11:47 -08:00
hmm.c
pagewalk: separate function pointers from iterator data
2019-09-07 04:28:04 -03:00
huge_memory.c
Merge branch 'hugepage-fallbacks' (hugepatch patches from David Rientjes)
2019-09-28 14:26:47 -07:00
hugetlb_cgroup.c
mm: introduce compound_nr()
2019-09-24 15:54:08 -07:00
hugetlb.c
hugetlbfs: don't retry when pool page allocations start to fail
2019-09-24 15:54:10 -07:00
hwpoison-inject.c
hwpoison-inject: no need to check return value of debugfs_create functions
2019-06-03 15:39:40 +02:00
init-mm.c
mm: use CPU_BITS_NONE to initialize init_mm.cpu_bitmask
2019-09-24 15:54:10 -07:00
internal.h
mm: introduce MADV_COLD
2019-09-25 17:51:41 -07:00
interval_tree.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 248
2019-06-19 17:09:08 +02:00
Kconfig
mm,thp: add read-only THP support for (non-shmem) FS
2019-09-24 15:54:11 -07:00
Kconfig.debug
mm, page_owner, debug_pagealloc: save and dump freeing stack trace
2019-09-24 15:54:08 -07:00
khugepaged.c
khugepaged: enable collapse pmd for pte-mapped THP
2019-09-24 15:54:11 -07:00
kmemleak-test.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333
2019-06-05 17:37:06 +02:00
kmemleak.c
mm/kmemleak.c: record the current memory pool size
2019-09-24 15:54:07 -07:00
ksm.c
mm: move memcmp_pages() and pages_identical()
2019-09-24 15:54:11 -07:00
list_lru.c
mm: memcg/slab: stop setting page->mem_cgroup pointer for slab pages
2019-07-12 11:05:44 -07:00
maccess.c
The main changes in this release include:
2019-07-18 11:51:00 -07:00
madvise.c
mm: factor out common parts between MADV_COLD and MADV_PAGEOUT
2019-09-25 17:51:41 -07:00
Makefile
mm: silence -Woverride-init/initializer-overrides
2019-09-24 15:54:10 -07:00
memblock.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
2019-05-30 11:26:32 -07:00
memcontrol.c
mm, memcg: proportional memory.{low,min} reclaim
2019-10-07 15:47:20 -07:00
memfd.c
mm: page cache: store only head pages in i_pages
2019-09-24 15:54:08 -07:00
memory_hotplug.c
mm/memory_hotplug.c: s/is/if
2019-09-24 15:54:09 -07:00
memory-failure.c
HMM patches for 5.3
2019-07-14 19:42:11 -07:00
memory.c
mm: fix double page fault on arm64 if PTE_AF is cleared
2019-10-18 11:11:29 +01:00
mempolicy.c
Merge branch 'hugepage-fallbacks' (hugepatch patches from David Rientjes)
2019-09-28 14:26:47 -07:00
mempool.c
docs/core-api/mm: fix return value descriptions in mm/
2019-03-05 21:07:20 -08:00
memremap.c
mm/memremap: drop unused SECTION_SIZE and SECTION_MASK
2019-10-07 15:47:19 -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
mm: untag user pointers passed to memory syscalls
2019-09-25 17:51:41 -07:00
mincore.c
mm: untag user pointers passed to memory syscalls
2019-09-25 17:51:41 -07:00
mlock.c
mm: untag user pointers passed to memory syscalls
2019-09-25 17:51:41 -07:00
mm_init.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
mmap.c
mm: untag user pointers in mmap/munmap/mremap/brk
2019-09-25 17:51:41 -07:00
mmu_context.c
…
mmu_gather.c
mm: remove quicklist page table caches
2019-09-24 15:54:09 -07:00
mmu_notifier.c
mm, notifier: Catch sleeping/blocking for !blockable
2019-09-07 04:28:05 -03:00
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
mm: untag user pointers passed to memory syscalls
2019-09-25 17:51:41 -07:00
mremap.c
mm: untag user pointers in mmap/munmap/mremap/brk
2019-09-25 17:51:41 -07:00
msync.c
mm: untag user pointers passed to memory syscalls
2019-09-25 17:51:41 -07:00
nommu.c
mm: introduce page_size()
2019-09-24 15:54:08 -07:00
oom_kill.c
mm: introduce MADV_COLD
2019-09-25 17:51:41 -07:00
page_alloc.c
mm/page_alloc.c: fix a crash in free_pages_prepare()
2019-10-07 15:47:19 -07:00
page_counter.c
memcg: introduce memory.min
2018-06-07 17:34:36 -07:00
page_ext.c
mm, debug_pagealloc: use a page type instead of page_ext flag
2019-07-12 11:05:43 -07:00
page_idle.c
mm/page_idle.c: fix oops because end_pfn is larger than max_pfn
2019-06-29 16:43:45 +08:00
page_io.c
mm, swap: use rbtree for swap_extent
2019-07-12 11:05:43 -07:00
page_isolation.c
mm/page_isolation.c: change the prototype of undo_isolate_page_range()
2019-07-12 11:05:43 -07:00
page_owner.c
mm, page_owner, debug_pagealloc: save and dump freeing stack trace
2019-09-24 15:54:08 -07:00
page_poison.c
mm/page_poison.c: fix a typo in a comment
2019-09-24 15:54:08 -07:00
page_vma_mapped.c
mm: introduce page_size()
2019-09-24 15:54:08 -07:00
page-writeback.c
writeback, memcg: Implement foreign dirty flushing
2019-08-27 09:22:38 -06:00
pagewalk.c
pagewalk: use lockdep_assert_held for locking validation
2019-09-07 04:28:04 -03:00
percpu-internal.h
percpu: convert chunk hints to be based on pcpu_block_md
2019-03-13 12:25:31 -07:00
percpu-km.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428
2019-06-05 17:37:16 +02:00
percpu-stats.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428
2019-06-05 17:37:16 +02:00
percpu-vm.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428
2019-06-05 17:37:16 +02:00
percpu.c
percpu: Use struct_size() helper
2019-09-04 13:40:49 -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
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
2019-05-30 11:26:32 -07:00
readahead.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
rmap.c
mm,thp: add read-only THP support for (non-shmem) FS
2019-09-24 15:54:11 -07:00
rodata_test.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
shmem.c
Merge branch 'work.mount3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2019-10-10 08:16:44 -07:00
shuffle.c
mm: fix -Wmissing-prototypes warnings
2019-10-07 15:47:19 -07:00
shuffle.h
mm: maintain randomization of page free lists
2019-05-14 19:52:48 -07:00
slab_common.c
mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)
2019-10-07 15:47:20 -07:00
slab.c
mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options
2019-07-12 11:05:46 -07:00
slab.h
mm, slab: move memcg_cache_params structure to mm/slab.h
2019-09-24 15:54:07 -07:00
slob.c
mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)
2019-10-07 15:47:20 -07:00
slub.c
mm, sl[ou]b: improve memory accounting
2019-10-07 15:47:20 -07:00
sparse-vmemmap.c
mm/sparsemem: convert kmalloc_section_memmap() to populate_section_memmap()
2019-07-18 17:08:07 -07:00
sparse.c
mm: fix -Wmissing-prototypes warnings
2019-10-07 15:47:19 -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
mm: page cache: store only head pages in i_pages
2019-09-24 15:54:08 -07:00
swap.c
mm: introduce MADV_COLD
2019-09-25 17:51:41 -07:00
swapfile.c
vfs: don't allow writes to swap files
2019-08-20 07:55:16 -07:00
truncate.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
usercopy.c
usercopy: Avoid HIGHMEM pfn warning
2019-09-17 15:20:17 -07:00
userfaultfd.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499
2019-06-19 17:09:53 +02:00
util.c
arm64, mm: make randomization selected by generic topdown mmap layout
2019-09-24 15:54:11 -07:00
vmacache.c
mm: get rid of vmacache_flush_all() entirely
2018-09-13 15:18:04 -10:00
vmalloc.c
augmented rbtree: add new RB_DECLARE_CALLBACKS_MAX macro
2019-09-25 17:51:39 -07:00
vmpressure.c
mm/vmpressure.c: fix a signedness bug in vmpressure_register_event()
2019-10-07 15:47:19 -07:00
vmscan.c
mm, memcg: make scan aggression always exclude protection
2019-10-07 15:47:20 -07:00
vmstat.c
mm,thp: stats for file backed THP
2019-09-24 15:54:11 -07:00
workingset.c
mm: workingset: fix vmstat counters for shadow nodes
2019-08-13 16:06:52 -07:00
z3fold.c
mm/z3fold.c: claim page in the beginning of free
2019-10-07 15:47:19 -07:00
zbud.c
treewide: Add SPDX license identifier for more missed files
2019-05-21 10:50:45 +02:00
zpool.c
zpool: add malloc_support_movable to zpool_driver
2019-09-24 15:54:12 -07:00
zsmalloc.c
mm/zsmalloc.c: fix a -Wunused-function warning
2019-09-24 15:54:12 -07:00
zswap.c
zswap: do not map same object twice
2019-09-24 15:54:12 -07:00