linux/mm
Mike Kravetz fa27759af4 hugetlb: clean up code checking for fault/truncation races
With the new hugetlb vma lock in place, it can also be used to handle page
fault races with file truncation.  The lock is taken at the beginning of
the code fault path in read mode.  During truncation, it is taken in write
mode for each vma which has the file mapped.  The file's size (i_size) is
modified before taking the vma lock to unmap.

How are races handled?

The page fault code checks i_size early in processing after taking the vma
lock.  If the fault is beyond i_size, the fault is aborted.  If the fault
is not beyond i_size the fault will continue and a new page will be added
to the file.  It could be that truncation code modifies i_size after the
check in fault code.  That is OK, as truncation code will soon remove the
page.  The truncation code will wait until the fault is finished, as it
must obtain the vma lock in write mode.

This patch cleans up/removes late checks in the fault paths that try to
back out pages racing with truncation.  As noted above, we just let the
truncation code remove the pages.

[mike.kravetz@oracle.com: fix reserve_alloc set but not used compiler warning]
  Link: https://lkml.kernel.org/r/Yyj7HsJWfHDoU24U@monkey
Link: https://lkml.kernel.org/r/20220914221810.95771-10-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: James Houghton <jthoughton@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Prakash Sangappa <prakash.sangappa@oracle.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:17 -07:00
..
damon mm/damon/core: simplify the kdamond stop mechanism by removing 'done' 2022-10-03 14:03:14 -07:00
kasan kasan: better invalid/double-free report header 2022-10-03 14:03:02 -07:00
kfence mm: kfence: convert to DEFINE_SEQ_ATTRIBUTE 2022-10-03 14:03:07 -07:00
backing-dev.c mm: backing-dev: Remove the unneeded result variable 2022-09-11 20:26:02 -07:00
balloon_compaction.c mm: Convert all PageMovable users to movable_operations 2022-08-02 12:34:03 -04:00
bootmem_info.c bootmem: remove the vmemmap pages from kmemleak in put_page_bootmem 2022-08-28 14:02:45 -07:00
cma_debug.c mm/cma_debug: show complete cma name in debugfs directories 2022-09-11 20:25:50 -07:00
cma_sysfs.c
cma.c Revert "mm/cma.c: remove redundant cma_mutex lock" 2022-05-13 15:11:26 -07:00
cma.h mm/cma: provide option to opt out from exposing pages on activation failure 2022-03-22 15:57:09 -07:00
compaction.c mm: add pageblock_aligned() macro 2022-10-03 14:03:04 -07:00
debug_page_ref.c
debug_vm_pgtable.c docs: rename Documentation/vm to Documentation/mm 2022-06-27 12:52:53 -07:00
debug.c mm: remove the vma linked list 2022-09-26 19:46:26 -07:00
dmapool.c mm/dmapool.c: revert "make dma pool to use kmalloc_node" 2022-01-15 16:30:28 +02:00
early_ioremap.c mm/early_ioremap: declare early_memremap_pgprot_adjust() 2022-03-22 15:57:11 -07:00
fadvise.c riscv: compat: syscall: Add compat_sys_call_table implementation 2022-04-26 13:36:25 -07:00
failslab.c mm: fix missing handler for __GFP_NOWARN 2022-05-19 14:08:55 -07:00
filemap.c mm/filemap: make folio_put_wait_locked static 2022-10-03 14:03:15 -07:00
folio-compat.c mm: remove try_to_free_swap() 2022-10-03 14:02:53 -07:00
frontswap.c frontswap: don't call ->init if no ops are registered 2022-09-26 12:14:34 -07:00
gup_test.c mm: rename is_pinnable_page() to is_longterm_pinnable_page() 2022-07-17 17:14:27 -07:00
gup_test.h
gup.c mm/gup: use gup_can_follow_protnone() also in GUP-fast 2022-09-26 19:46:28 -07:00
highmem.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
hmm.c mm/swap: add swp_offset_pfn() to fetch PFN from swap entry 2022-09-26 19:46:05 -07:00
huge_memory.c mm/huge_memory: prevent THP_ZERO_PAGE_ALLOC increased twice 2022-10-03 14:03:08 -07:00
hugetlb_cgroup.c hugetlb_cgroup: use helper for_each_hstate and hstate_index 2022-09-11 20:25:53 -07:00
hugetlb_vmemmap.c mm: hugetlb_vmemmap: simplify reset_struct_pages() 2022-09-11 20:25:58 -07:00
hugetlb_vmemmap.h mm: hugetlb_vmemmap: improve hugetlb_vmemmap code readability 2022-08-08 18:06:43 -07:00
hugetlb.c hugetlb: clean up code checking for fault/truncation races 2022-10-03 14:03:17 -07:00
hwpoison-inject.c mm/hwpoison: add __init/__exit annotations to module init/exit funcs 2022-10-03 14:03:05 -07:00
init-mm.c mm: remove rb tree. 2022-09-26 19:46:16 -07:00
internal.h mm: use nth_page instead of mem_map_offset mem_map_next 2022-10-03 14:03:08 -07:00
interval_tree.c
io-mapping.c
ioremap.c mm: ioremap: Add ioremap/iounmap_allowed() 2022-06-27 12:22:31 +01:00
Kconfig mm: multi-gen LRU: admin guide 2022-09-26 19:46:10 -07:00
Kconfig.debug Two followon fixes for the post-5.19 series "Use pageblock_order for cma 2022-05-27 11:40:49 -07:00
khugepaged.c khugepaged: call shmem_get_folio() 2022-10-03 14:02:50 -07:00
kmemleak.c mm/kmemleak: make create_object return void 2022-09-11 20:26:10 -07:00
ksm.c ksm: use a folio in replace_page() 2022-10-03 14:02:53 -07:00
list_lru.c mm: kmem: make mem_cgroup_from_obj() vmalloc()-safe 2022-06-16 19:48:31 -07:00
maccess.c asm-generic updates for 5.18 2022-03-23 18:03:08 -07:00
madvise.c madvise: convert madvise_free_pte_range() to use a folio 2022-10-03 14:02:52 -07:00
Makefile mm: remove vmacache 2022-09-26 19:46:18 -07:00
mapping_dirty_helpers.c mm: move tlb_flush_pending inline helpers to mm_inline.h 2022-01-15 16:30:27 +02:00
memblock.c mm: add pageblock_align() macro 2022-10-03 14:03:04 -07:00
memcontrol.c mm/memcontrol: use kstrtobool for swapaccount param parsing 2022-10-03 14:03:14 -07:00
memfd.c memfd: fix F_SEAL_WRITE after shmem huge page allocated 2022-03-05 11:08:32 -08:00
memory_hotplug.c mm: add pageblock_aligned() macro 2022-10-03 14:03:04 -07:00
memory-failure.c rmap: remove page_unlock_anon_vma_read() 2022-10-03 14:02:54 -07:00
memory-tiers.c mm/demotion: expose memory tier details via sysfs 2022-09-26 19:46:13 -07:00
memory.c hugetlb: use new vma_lock for pmd sharing synchronization 2022-10-03 14:03:17 -07:00
mempolicy.c mm/mempolicy: use PAGE_ALIGN instead of open-coding it 2022-10-03 14:03:15 -07:00
mempool.c mm/mempool: use might_alloc() 2022-06-16 19:48:30 -07:00
memremap.c mm/mremap_pages: save a few cycles in get_dev_pagemap() 2022-09-11 20:26:11 -07:00
memtest.c
migrate_device.c mm: remember young/dirty bit for page migrations 2022-09-26 19:46:05 -07:00
migrate.c mm: convert page_get_anon_vma() to folio_get_anon_vma() 2022-10-03 14:02:54 -07:00
mincore.c mm: teach core mm about pte markers 2022-05-13 07:20:09 -07:00
mlock.c mm/mlock: drop dead code in count_mm_mlocked_page_nr() 2022-09-26 19:46:27 -07:00
mm_init.c mm: multi-gen LRU: groundwork 2022-09-26 19:46:09 -07:00
mm_slot.h mm: introduce common struct mm_slot 2022-10-03 14:02:43 -07:00
mmap_lock.c
mmap.c mm: refactor of vma_merge() 2022-09-26 19:46:27 -07:00
mmu_gather.c mm/mmu_gather: limit free batch count and add schedule point in tlb_batch_pages_flush 2022-04-28 23:16:12 -07:00
mmu_notifier.c mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove() 2022-04-21 20:01:10 -07:00
mmzone.c mm: multi-gen LRU: groundwork 2022-09-26 19:46:09 -07:00
mprotect.c mm/mprotect: use maple tree navigation instead of VMA linked list 2022-09-26 19:46:24 -07:00
mremap.c mm: add merging after mremap resize 2022-09-26 19:46:28 -07:00
msync.c mm/msync: use vma_find() instead of vma linked list 2022-09-26 19:46:25 -07:00
nommu.c mm: remove the vma linked list 2022-09-26 19:46:26 -07:00
oom_kill.c mm: reduce noise in show_mem for lowmem allocations 2022-09-26 19:46:29 -07:00
page_alloc.c mm/page_alloc.c: document bulkfree_pcp_prepare() return value 2022-10-03 14:03:14 -07:00
page_counter.c mm: page_counter: remove unneeded atomic ops for low/min 2022-09-11 20:26:01 -07:00
page_ext.c page_ext: introduce boot parameter 'early_page_ext' 2022-09-11 20:26:02 -07:00
page_idle.c mm: don't be stuck to rmap lock on reclaim path 2022-05-19 14:08:54 -07:00
page_io.c swap: convert swap_writepage() to use a folio 2022-10-03 14:02:52 -07:00
page_isolation.c mm: add pageblock_aligned() macro 2022-10-03 14:03:04 -07:00
page_owner.c mm: reuse pageblock_start/end_pfn() macro 2022-10-03 14:03:03 -07:00
page_poison.c
page_reporting.c
page_reporting.h
page_table_check.c mm: fix use-after free of page_ext after race with memory-offline 2022-09-11 20:25:57 -07:00
page_vma_mapped.c mm/swap: add swp_offset_pfn() to fetch PFN from swap entry 2022-09-26 19:46:05 -07:00
page-writeback.c writeback: avoid use-after-free after removing device 2022-08-28 14:02:43 -07:00
pagewalk.c mm/pagewalk: use vma_find() instead of vma linked list 2022-09-26 19:46:25 -07:00
percpu-internal.h percpu: improve percpu_alloc_percpu event trace 2022-05-13 07:20:18 -07:00
percpu-km.c
percpu-stats.c mm: use vmalloc_array and vcalloc for array allocations 2022-03-08 09:30:46 -05:00
percpu-vm.c
percpu.c mm: percpu: use kmemleak_ignore_phys() instead of kmemleak_free() 2022-07-17 17:14:47 -07:00
pgalloc-track.h
pgtable-generic.c mm: avoid unnecessary flush on change_huge_pmd() 2022-05-13 07:20:05 -07:00
process_vm_access.c
ptdump.c mm: sparsemem: use page table lock to protect kernel pmd operations 2022-03-22 15:57:08 -07:00
readahead.c filemap: Fix serialization adding transparent huge pages to page cache 2022-06-23 12:22:00 -04:00
rmap.c hugetlb: use new vma_lock for pmd sharing synchronization 2022-10-03 14:03:17 -07:00
rodata_test.c mm/rodata_test: use PAGE_ALIGNED() helper 2022-10-03 14:03:05 -07:00
secretmem.c mm: fix dereferencing possible ERR_PTR 2022-09-11 16:22:31 -07:00
shmem.c tmpfs: add support for an i_version counter 2022-10-03 14:03:06 -07:00
shrinker_debug.c mm: shrinkers: fix double kfree on shrinker name 2022-07-29 18:07:13 -07:00
shuffle.c mm/shuffle: convert module_param_call to module_param_cb 2022-10-03 14:03:07 -07:00
shuffle.h
slab_common.c mm/slab_common: move generic bulk alloc/free functions to SLOB 2022-07-20 13:30:12 +02:00
slab.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
slab.h mm/slab_common: move generic bulk alloc/free functions to SLOB 2022-07-20 13:30:12 +02:00
slob.c mm/slab_common: move generic bulk alloc/free functions to SLOB 2022-07-20 13:30:12 +02:00
slub.c kfence: add sysfs interface to disable kfence for selected slabs. 2022-09-11 20:25:52 -07:00
sparse-vmemmap.c mm: hugetlb_vmemmap: move vmemmap code related to HugeTLB to hugetlb_vmemmap.c 2022-08-08 18:06:42 -07:00
sparse.c mm: memory_hotplug: enumerate all supported section flags 2022-07-03 18:08:49 -07:00
swap_cgroup.c mm: use vmalloc_array and vcalloc for array allocations 2022-03-08 09:30:46 -05:00
swap_slots.c mm/swap: convert put_swap_page() to put_swap_folio() 2022-10-03 14:02:46 -07:00
swap_state.c swap_state: convert free_swap_cache() to use a folio 2022-10-03 14:02:51 -07:00
swap.c mm: add folio_add_lru_vma() 2022-10-03 14:02:45 -07:00
swap.h mm: remove lookup_swap_cache() 2022-10-03 14:02:51 -07:00
swapfile.c memcg: convert mem_cgroup_swap_full() to take a folio 2022-10-03 14:02:53 -07:00
truncate.c mm: add split_folio() 2022-10-03 14:02:45 -07:00
usercopy.c usercopy: use unsigned long instead of uintptr_t 2022-07-01 17:03:38 -07:00
userfaultfd.c hugetlb: use new vma_lock for pmd sharing synchronization 2022-10-03 14:03:17 -07:00
util.c mm: remove the vma linked list 2022-09-26 19:46:26 -07:00
vmalloc.c mm/vmalloc: extend find_vmap_lowest_match_check with extra arguments 2022-09-11 20:26:05 -07:00
vmpressure.c
vmscan.c memcg: convert mem_cgroup_swap_full() to take a folio 2022-10-03 14:02:53 -07:00
vmstat.c mm: remove vmacache 2022-09-26 19:46:18 -07:00
workingset.c mm: multi-gen LRU: minimal implementation 2022-09-26 19:46:09 -07:00
z3fold.c mm: Convert all PageMovable users to movable_operations 2022-08-02 12:34:03 -04:00
zbud.c
zpool.c zpool: remove the list of pools_head 2022-01-15 16:30:31 +02:00
zsmalloc.c zsmalloc: use correct types in _first_obj_offset functions 2022-10-03 14:03:07 -07:00
zswap.c mm/swap: remove the end_write_func argument to __swap_writepage 2022-09-11 20:25:50 -07:00