linux/mm
Linus Torvalds d6a5c7a1a6 mm: introduce new 'lock_mm_and_find_vma()' page fault helper
commit c2508ec5a5 upstream.

.. and make x86 use it.

This basically extracts the existing x86 "find and expand faulting vma"
code, but extends it to also take the mmap lock for writing in case we
actually do need to expand the vma.

We've historically short-circuited that case, and have some rather ugly
special logic to serialize the stack segment expansion (since we only
hold the mmap lock for reading) that doesn't match the normal VM
locking.

That slight violation of locking worked well, right up until it didn't:
the maple tree code really does want proper locking even for simple
extension of an existing vma.

So extract the code for "look up the vma of the fault" from x86, fix it
up to do the necessary write locking, and make it available as a helper
function for other architectures that can use the common helper.

Note: I say "common helper", but it really only handles the normal
stack-grows-down case.  Which is all architectures except for PA-RISC
and IA64.  So some rare architectures can't use the helper, but if they
care they'll just need to open-code this logic.

It's also worth pointing out that this code really would like to have an
optimistic "mmap_upgrade_trylock()" to make it quicker to go from a
read-lock (for the common case) to taking the write lock (for having to
extend the vma) in the normal single-threaded situation where there is
no other locking activity.

But that _is_ all the very uncommon special case, so while it would be
nice to have such an operation, it probably doesn't matter in reality.
I did put in the skeleton code for such a possible future expansion,
even if it only acts as pseudo-documentation for what we're doing.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[6.1: Ignore CONFIG_PER_VMA_LOCK context]
Signed-off-by: Samuel Mendoza-Jonas <samjonas@amazon.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-01 13:16:24 +02:00
..
damon mm/damon/paddr: fix missing folio_put() 2023-03-10 09:34:20 +01:00
kasan kasan: hw_tags: avoid invalid virt_to_page() 2023-05-11 23:03:39 +09:00
kfence mm: kfence: fix handling discontiguous page 2023-04-13 16:55:30 +02:00
kmsan mm: kmsan: handle alloc failures in kmsan_vmap_pages_range_noflush() 2023-04-26 14:28:41 +02:00
backing-dev.c writeback, cgroup: fix null-ptr-deref write in bdi_split_work_to_wbs 2023-04-26 14:28:39 +02:00
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 Revert "mm/compaction: fix set skip in fast_find_migrateblock" 2023-02-01 08:34:49 +01:00
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
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 unexpected changes to {failslab|fail_page_alloc}.attr 2022-11-22 18:50:44 -08:00
filemap.c mm/filemap: fix page end in filemap_get_read_batch 2023-02-22 12:59:49 +01:00
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: add folio to list when folio_isolate_lru() succeed 2023-02-22 12:59:54 +01:00
highmem.c highmem: fix kmap_to_page() for kmap_local_page() addresses 2022-10-12 18:51:51 -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.c: warn with pr_warn_ratelimited instead of VM_WARN_ON_ONCE_FOLIO 2023-04-26 14:28:41 +02:00
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: include missing linux/moduleparam.h 2022-11-08 15:57:23 -08:00
hugetlb_vmemmap.h mm: hugetlb_vmemmap: improve hugetlb_vmemmap code readability 2022-08-08 18:06:43 -07:00
hugetlb.c mm/hugetlb: fix uffd wr-protection for CoW optimization path 2023-04-13 16:55:36 +02:00
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/page_alloc: make boot_nodestats static 2022-10-03 14:03:30 -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: introduce new 'lock_mm_and_find_vma()' page fault helper 2023-07-01 13:16:24 +02:00
Kconfig.debug mm: page_table_check: Make it dependent on EXCLUSIVE_SYSTEM_RAM 2023-06-14 11:15:29 +02:00
khugepaged.c mm/khugepaged: check again on anon uffd-wp during isolation 2023-04-26 14:28:41 +02:00
kmemleak.c mm/kmemleak: prevent soft lockup in kmemleak_scan()'s object iteration loops 2022-10-28 13:37:22 -07:00
ksm.c mm/ksm: fix race with VMA iteration and mm_struct teardown 2023-03-30 12:49:29 +02:00
list_lru.c mm: kmem: make mem_cgroup_from_obj() vmalloc()-safe 2022-06-16 19:48:31 -07:00
maccess.c mm: Fix copy_from_user_nofault(). 2023-06-28 11:12:17 +02:00
madvise.c use less confusing names for iov_iter direction initializers 2023-02-09 11:28:04 +01:00
Makefile mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol 2022-10-03 14:03:36 -07:00
mapping_dirty_helpers.c
memblock.c Revert "mm: Always release pages to the buddy allocator in memblock_free_late()." 2023-02-22 12:59:50 +01:00
memcontrol.c mm: memcontrol: deprecate charge moving 2023-03-10 09:34:26 +01:00
memfd.c memfd: check for non-NULL file_seals in memfd_create() syscall 2023-06-28 11:12:27 +02:00
memory_hotplug.c mm: add pageblock_aligned() macro 2022-10-03 14:03:04 -07:00
memory-failure.c mm/hwpoison: convert TTU_IGNORE_HWPOISON to TTU_HWPOISON 2023-03-10 09:34:25 +01:00
memory-tiers.c memory tier: release the new_memtier in find_create_memory_tier() 2023-03-10 09:34:27 +01:00
memory.c mm: introduce new 'lock_mm_and_find_vma()' page fault helper 2023-07-01 13:16:24 +02:00
mempolicy.c mm/mempolicy: correctly update prev when policy is equal on mbind 2023-05-11 23:03:41 +09:00
mempool.c mm/mempool: use might_alloc() 2022-06-16 19:48:30 -07:00
memremap.c mm/memremap.c: map FS_DAX device memory as decrypted 2022-11-08 15:57:23 -08:00
memtest.c
migrate_device.c mm/migrate_device: return number of migrating pages in args->cpages 2022-11-22 18:50:43 -08:00
migrate.c mm/migrate: fix wrongly apply write bit after mkdirty on sparc64 2023-02-22 12:59:49 +01:00
mincore.c mm: teach mincore_hugetlb about pte markers 2023-03-22 13:34:03 +01:00
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/mmap: Fix error return in do_vmi_align_munmap() 2023-07-01 13:16:22 +02:00
mmu_gather.c mm/khugepaged: fix GUP-fast interaction by sending IPI 2022-11-30 14:49:42 -08:00
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/uffd: fix warning without PTE_MARKER_UFFD_WP compiled in 2022-10-12 15:56:46 -07:00
mremap.c mm, mremap: fix mremap() expanding for vma's with vm_ops->close() 2023-02-09 11:28:22 +01:00
msync.c mm/msync: use vma_find() instead of vma linked list 2022-09-26 19:46:25 -07:00
nommu.c nommu: fix split_vma() map_count error 2023-01-24 07:24:33 +01:00
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: fix potential deadlock on zonelist_update_seq seqlock 2023-04-26 14:28:44 +02:00
page_counter.c mm: page_counter: remove unneeded atomic ops for low/min 2022-09-11 20:26:01 -07:00
page_ext.c mm/page_exit: fix kernel doc warning in page_ext_put() 2022-11-22 18:50:41 -08:00
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 use less confusing names for iov_iter direction initializers 2023-02-09 11:28:04 +01:00
page_isolation.c mm/page_isolation: fix clang deadcode warning 2022-10-28 13:37:22 -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: page_table_check: Ensure user pages are not slab pages 2023-06-14 11:15:29 +02:00
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 mm: export balance_dirty_pages_ratelimited_flags() 2022-09-26 12:28:07 +02:00
pagewalk.c - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -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
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 use less confusing names for iov_iter direction initializers 2023-02-09 11:28:04 +01:00
ptdump.c mm: pagewalk: Fix race between unmap and page walker 2022-09-03 10:13:13 -07:00
readahead.c mm: add PSI accounting around ->read_folio and ->readahead calls 2022-09-20 08:24:38 -06:00
rmap.c mm/hwpoison: convert TTU_IGNORE_HWPOISON to TTU_HWPOISON 2023-03-10 09:34:25 +01:00
rodata_test.c mm/rodata_test: use PAGE_ALIGNED() helper 2022-10-03 14:03:05 -07:00
secretmem.c mm/secretmem: remove reduntant return value 2022-10-03 14:03:36 -07:00
shmem.c mm/shmem: restore SHMEM_HUGE_DENY precedence over MADV_COLLAPSE 2023-01-24 07:24:33 +01:00
shrinker_debug.c mm: shrinkers: fix deadlock in shrinker debugfs 2023-02-22 12:59:46 +01:00
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: remove duplicate kernel-doc comment for ksize() 2022-11-07 17:11:27 +01:00
slab.c mm/slab: Fix undefined init_cache_node_node() for NUMA and !SMP 2023-03-30 12:49:23 +02:00
slab.h - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -07:00
slob.c Merge branch 'slab/for-6.1/kmalloc_size_roundup' into slab/for-next 2022-09-29 11:30:55 +02:00
slub.c treewide: use prandom_u32_max() when possible, part 1 2022-10-11 17:42:55 -06:00
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: memcontrol: don't allocate cgroup swap arrays when memcg is disabled 2022-10-03 14:03:36 -07:00
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 mm/swap: fix swap_info_struct race between swapoff and get_swap_pages() 2023-04-13 16:55:36 +02:00
truncate.c mm: add split_folio() 2022-10-03 14:02:45 -07:00
usercopy.c mm: Fix copy_from_user_nofault(). 2023-06-28 11:12:17 +02:00
userfaultfd.c mm/shmem: use page_mapping() to detect page cache for uffd continue 2022-11-08 15:57:23 -08:00
util.c - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -07:00
vmalloc.c mm: kmsan: handle alloc failures in kmsan_vmap_pages_range_noflush() 2023-04-26 14:28:41 +02:00
vmpressure.c
vmscan.c mm: do not reclaim private data from pinned page 2023-05-11 23:03:39 +09:00
vmstat.c - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -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
zsmalloc.c zsmalloc: zs_destroy_pool: add size_class NULL check 2022-10-20 21:27:21 -07:00
zswap.c zswap: do not shrink if cgroup may not zswap 2023-06-21 16:00:54 +02:00