linux-stable/mm
Jan Kara f2c57d91b0 mm: Fix warning in insert_pfn()
In DAX mode a write pagefault can race with write(2) in the following
way:

CPU0                            CPU1
                                write fault for mapped zero page (hole)
dax_iomap_rw()
  iomap_apply()
    xfs_file_iomap_begin()
      - allocates blocks
    dax_iomap_actor()
      invalidate_inode_pages2_range()
        - invalidates radix tree entries in given range
                                dax_iomap_pte_fault()
                                  grab_mapping_entry()
                                    - no entry found, creates empty
                                  ...
                                  xfs_file_iomap_begin()
                                    - finds already allocated block
                                  ...
                                  vmf_insert_mixed_mkwrite()
                                    - WARNs and does nothing because there
                                      is still zero page mapped in PTE
        unmap_mapping_pages()

This race results in WARN_ON from insert_pfn() and is occasionally
triggered by fstest generic/344. Note that the race is otherwise
harmless as before write(2) on CPU0 is finished, we will invalidate page
tables properly and thus user of mmap will see modified data from
write(2) from that point on. So just restrict the warning only to the
case when the PFN in PTE is not zero page.

Link: http://lkml.kernel.org/r/20180824154542.26872-1-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:17 -07:00
..
kasan mm: remove include/linux/bootmem.h 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
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
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
dmapool.c mm: use octal not symbolic permissions 2018-06-15 07:55:25 +09:00
early_ioremap.c
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 Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
frame_vector.c
frontswap.c mm: use octal not symbolic permissions 2018-06-15 07:55:25 +09:00
gup.c mm/gup: cache dev_pagemap while pinning pages 2018-10-26 16:38:15 -07:00
gup_benchmark.c mm/gup_benchmark.c: prevent integer overflow in ioctl 2018-10-31 08:54:12 -07:00
highmem.c
hmm.c mm/hmm: invalidate device page table at start of invalidation 2018-10-31 08:54:12 -07:00
huge_memory.c Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
hugetlb.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
hugetlb_cgroup.c mm: rename page_counter's count/limit into usage/max 2018-06-07 17:34:35 -07:00
hwpoison-inject.c
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
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
khugepaged.c mm: Convert khugepaged_scan_shmem to XArray 2018-10-21 10:46:38 -04:00
kmemleak-test.c
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
Makefile mm: remove nobootmem 2018-10-31 08:54:16 -07:00
memblock.c mm/memblock.c: warn if zero alignment was requested 2018-10-31 08:54:17 -07:00
memcontrol.c Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -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 mm/memory_hotplug: fix online/offline_pages called w.o. mem_hotplug_lock 2018-10-31 08:54:17 -07:00
mempolicy.c mm/mempolicy.c: use match_string() helper to simplify the code 2018-10-26 16:26:33 -07:00
mempool.c mm/mempool.c: add missing parameter description 2018-08-22 10:52:44 -07:00
memtest.c
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
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
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
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 memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
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 mm: split SWP_FILE into SWP_ACTIVATED and SWP_FS 2018-10-26 16:38:15 -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 memblock: rename free_all_bootmem to memblock_free_all 2018-10-31 08:54:16 -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
percpu-internal.h
percpu-km.c
percpu-stats.c treewide: Use array_size() in vmalloc() 2018-06-12 16:19:22 -07:00
percpu-vm.c
percpu.c memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -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
quicklist.c
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
shmem.c shmem: Comment fixups 2018-10-21 10:46:41 -04:00
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
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: export add_swap_extent() 2018-10-26 16:38:15 -07:00
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 reclaim lock-ups 2018-05-11 17:28:45 -07:00
zbud.c
zpool.c
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