linux/mm
Jan Kara 145faa3d03 Revert "mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again"
commit 30139c7020 upstream.

Patch series "mm: Avoid possible overflows in dirty throttling".

Dirty throttling logic assumes dirty limits in page units fit into
32-bits.  This patch series makes sure this is true (see patch 2/2 for
more details).


This patch (of 2):

This reverts commit 9319b64790.

The commit is broken in several ways.  Firstly, the removed (u64) cast
from the multiplication will introduce a multiplication overflow on 32-bit
archs if wb_thresh * bg_thresh >= 1<<32 (which is actually common - the
default settings with 4GB of RAM will trigger this).  Secondly, the
div64_u64() is unnecessarily expensive on 32-bit archs.  We have
div64_ul() in case we want to be safe & cheap.  Thirdly, if dirty
thresholds are larger than 1<<32 pages, then dirty balancing is going to
blow up in many other spectacular ways anyway so trying to fix one
possible overflow is just moot.

Link: https://lkml.kernel.org/r/20240621144017.30993-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20240621144246.11148-1-jack@suse.cz
Fixes: 9319b64790 ("mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-By: Zach O'Keefe <zokeefe@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-18 13:05:43 +02:00
..
kasan kasan: print the original fault addr when access invalid shadow 2023-11-08 17:30:43 +01:00
backing-dev.c writeback, cgroup: remove extra percpu_ref_exit() 2023-05-30 12:57:56 +01:00
balloon_compaction.c
cleancache.c
cma_debug.c debugfs: make sure we can remove u32_array files cleanly 2020-07-10 13:54:00 -07:00
cma.c mm/cma: use nth_page() in place of direct struct page manipulation 2023-11-28 16:54:58 +00:00
cma.h mm: cma: use CMA_MAX_NAME to define the length of cma name array 2020-09-01 09:19:43 +02:00
compaction.c mm, vmscan: prevent infinite loop for costly GFP_NOIO | __GFP_RETRY_MAYFAIL allocations 2024-04-13 12:59:22 +02:00
debug_page_ref.c
debug_vm_pgtable.c mm/debug_vm_pgtable: remove pte entry from the page table 2022-02-08 18:30:35 +01:00
debug.c mm, dump_page: rename head_mapcount() --> head_compound_mapcount() 2020-10-13 18:38:29 -07:00
dmapool.c mm/dmapool.c: replace hard coded function name with __func__ 2020-10-13 18:38:32 -07:00
early_ioremap.c
fadvise.c mm, fadvise: improve the expensive remote LRU cache draining after FADV_DONTNEED 2020-10-13 18:38:29 -07:00
failslab.c
filemap.c mm/filemap: fix infinite loop in generic_file_buffered_read() 2023-09-23 11:01:10 +02:00
frame_vector.c media: vb2: frame_vector.c: replace WARN_ONCE with a comment 2023-10-10 21:53:33 +02:00
frontswap.c mm/frontswap: mark various intentional data races 2020-08-14 19:56:56 -07:00
gup_benchmark.c mm/gup_benchmark: take the mmap lock around GUP 2020-10-18 09:27:09 -07:00
gup.c mm/migration: return errno when isolate_huge_page failed 2023-02-15 17:22:21 +01:00
highmem.c mm/highmem.c: clean up endif comments 2020-10-16 11:11:18 -07:00
hmm.c mm/hmm.c: allow VM_MIXEDMAP to work with hmm_range_fault 2022-01-27 10:54:36 +01:00
huge_memory.c mm/userfaultfd: propagate uffd-wp bit when PTE-mapping the huge zeropage 2023-03-22 13:30:04 +01:00
hugetlb_cgroup.c hugetlb_cgroup: fix imbalanced css_get and css_put pair for shared mappings 2021-03-30 14:31:54 +02:00
hugetlb.c mm/hugetlb: change hugetlb_reserve_pages() to type bool 2024-03-15 10:48:22 -04:00
hwpoison-inject.c mm,hwpoison-inject: don't pin for hwpoison_filter 2020-10-16 11:11:16 -07:00
init-mm.c mm/gup: prevent gup_fast from racing with COW during fork 2020-12-30 11:53:54 +01:00
internal.h mm/thp: fix vma_address() if virtual address below file offset 2021-06-30 08:47:27 -04:00
interval_tree.c
ioremap.c mm: move p?d_alloc_track to separate header file 2020-08-07 11:33:26 -07:00
Kconfig mm/zsmalloc.c: drop ZSMALLOC_PGTABLE_MAPPING 2020-12-06 10:19:07 -08:00
Kconfig.debug treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
khugepaged.c mm/khugepaged: check again on anon uffd-wp during isolation 2023-04-26 11:27:38 +02:00
kmemleak.c Revert "mm: kmemleak: take a full lowmem check in kmemleak_*_phys()" 2022-09-15 11:32:02 +02:00
ksm.c ksm: fix potential missing rmap_item for stable_node 2021-05-19 10:13:07 +02:00
list_lru.c mm: list_lru: set shrinker map bit when child nr_items is not zero 2020-12-06 10:19:07 -08:00
maccess.c maccess: Fix writing offset in case of fault in strncpy_from_kernel_nofault() 2022-11-25 17:45:53 +01:00
madvise.c fs: add file and path permissions helpers 2024-06-21 14:52:58 +02:00
Makefile mm,kmemleak-test.c: move kmemleak-test.c to samples dir 2020-10-13 18:38:27 -07:00
mapping_dirty_helpers.c
memblock.c Revert "mm: Always release pages to the buddy allocator in memblock_free_late()." 2023-02-22 12:55:56 +01:00
memcontrol.c fs: add file and path permissions helpers 2024-06-21 14:52:58 +02:00
memfd.c memfd: check for non-NULL file_seals in memfd_create() syscall 2023-06-28 10:28:09 +02:00
memory_hotplug.c mm/memory_hotplug: use pfn math in place of direct struct page manipulation 2023-11-28 16:54:58 +00:00
memory-failure.c mm/memory-failure: fix an incorrect use of tail pages 2024-04-13 12:59:01 +02:00
memory.c x86/mm/pat: fix VM_PAT handling in COW mappings 2024-04-13 12:59:56 +02:00
mempolicy.c migrate: hugetlb: check for hugetlb shared PMD in node migration 2023-02-15 17:22:21 +01:00
mempool.c mm/mempool: add 'else' to split mutually exclusive case 2020-10-13 18:38:34 -07:00
memremap.c mm/memremap.c: map FS_DAX device memory as decrypted 2022-11-16 09:57:17 +01:00
memtest.c memtest: use {READ,WRITE}_ONCE in memory scanning 2024-04-13 12:58:39 +02:00
migrate.c mm/migrate: set swap entry values of THP tail pages properly. 2024-04-13 12:59:02 +02:00
mincore.c fs: add file and path permissions helpers 2024-06-21 14:52:58 +02:00
mlock.c mlock: fix unevictable_pgs event counts on THP 2020-09-19 13:13:38 -07:00
mm_init.c mm: adjust vm_committed_as_batch according to vm overcommit policy 2020-08-07 11:33:26 -07:00
mmap.c mm/mmap: undo ->mmap() when arch_validate_flags() fails 2022-10-26 13:25:11 +02:00
mmu_gather.c mm/khugepaged: fix GUP-fast interaction by sending IPI 2022-12-14 11:31:55 +01:00
mmu_notifier.c mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove() 2022-04-27 13:53:54 +02:00
mmzone.c arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2022-05-15 20:00:09 +02:00
mprotect.c mm: don't try to NUMA-migrate COW pages that have other uses 2022-02-23 12:00:57 +01:00
mremap.c mm/mremap: hold the rmap lock in write mode when moving page table entries. 2022-08-21 15:15:21 +02:00
msync.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
nommu.c mm: remove alloc_vm_area 2020-10-18 09:27:10 -07:00
oom_kill.c oom_kill.c: futex: delay the OOM reaper to allow time for proper futex cleanup 2022-04-27 13:53:54 +02:00
page_alloc.c mm, vmscan: prevent infinite loop for costly GFP_NOIO | __GFP_RETRY_MAYFAIL allocations 2024-04-13 12:59:22 +02:00
page_counter.c mm/page_counter: correct the obsolete func name in the comment of page_counter_try_charge() 2020-10-13 18:38:30 -07:00
page_ext.c
page_idle.c mm/page_idle.c: skip offline pages 2020-06-08 11:05:55 -07:00
page_io.c mm: fix unexpected zeroed page mapping with zram swap 2022-04-20 09:23:25 +02:00
page_isolation.c mm: rename page_order() to buddy_order() 2020-10-16 11:11:19 -07:00
page_owner.c mm: rename page_order() to buddy_order() 2020-10-16 11:11:19 -07:00
page_poison.c mm/page_poison.c: replace bool variable with static key 2020-10-16 11:11:17 -07:00
page_reporting.c mm: rename page_order() to buddy_order() 2020-10-16 11:11:19 -07:00
page_reporting.h mm: introduce include/linux/pgtable.h 2020-06-09 09:39:13 -07:00
page_vma_mapped.c mm/thp: another PVMW_SYNC fix in page_vma_mapped_walk() 2021-06-30 08:47:29 -04:00
page-writeback.c Revert "mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again" 2024-07-18 13:05:43 +02:00
pagewalk.c mm: pagewalk: Fix race between unmap and page walker 2022-09-08 11:11:38 +02:00
percpu-internal.h percpu: make pcpu_nr_empty_pop_pages per chunk type 2021-04-14 08:42:03 +02:00
percpu-km.c mm: memcg/percpu: account percpu memory to memory cgroups 2020-08-12 10:57:55 -07:00
percpu-stats.c percpu: make pcpu_nr_empty_pop_pages per chunk type 2021-04-14 08:42:03 +02:00
percpu-vm.c mm: memcg/percpu: account percpu memory to memory cgroups 2020-08-12 10:57:55 -07:00
percpu.c percpu: make pcpu_nr_empty_pop_pages per chunk type 2021-04-14 08:42:03 +02:00
pgalloc-track.h mm: move p?d_alloc_track to separate header file 2020-08-07 11:33:26 -07:00
pgtable-generic.c mm/thp: fix __split_huge_pmd_locked() on shmem migration entry 2021-06-30 08:47:26 -04:00
process_vm_access.c mm/process_vm_access.c: include compat.h 2021-01-19 18:27:21 +01:00
ptdump.c mm: pagewalk: Fix race between unmap and page walker 2022-09-08 11:11:38 +02:00
readahead.c vfs: fix readahead(2) on block devices 2023-11-20 11:06:44 +01:00
rmap.c mm/rmap: Fix anon_vma->degree ambiguity leading to double-reuse 2022-09-05 10:28:56 +02:00
rodata_test.c mm/rodata_test.c: fix missing function declaration 2020-08-21 09:52:53 -07:00
shmem.c tmpfs: verify {g,u}id mount options correctly 2023-09-19 12:20:06 +02:00
shuffle.c mm: rename page_order() to buddy_order() 2020-10-16 11:11:19 -07:00
shuffle.h mm/shuffle: remove dynamic reconfiguration 2020-08-07 11:33:29 -07:00
slab_common.c mm/slub: fix redzoning for small allocations 2021-06-23 14:42:54 +02:00
slab.c mm/sl?b.c: remove ctor argument from kmem_cache_flags 2021-05-14 09:50:45 +02:00
slab.h mm: kmemleak: slob: respect SLAB_NOLEAKTRACE flag 2021-11-26 10:39:19 +01:00
slob.c mm: memcg: convert vmstat slab counters to bytes 2020-08-07 11:33:24 -07:00
slub.c mm/slub: fix to return errno if kmalloc() fails 2022-09-28 11:10:28 +02:00
sparse-vmemmap.c mm/sparse: only sub-section aligned range would be populated 2020-08-07 11:33:27 -07:00
sparse.c mm/sparsemem: fix race in accessing memory_section->usage 2024-02-23 08:42:00 +01:00
swap_cgroup.c mm: memcontrol: make swap tracking an integral part of memory control 2020-06-03 20:09:48 -07:00
swap_slots.c mm/swap_slots.c: remove always zero and unused return value of enable_swap_slots_cache() 2020-10-13 18:38:30 -07:00
swap_state.c mm: swap: get rid of livelock in swapin readahead 2022-03-23 09:13:27 +01:00
swap.c mm: move call to compound_head() in release_pages() 2020-10-13 18:38:33 -07:00
swapfile.c mm: swap: fix race between free_swap_and_cache() and swapoff() 2024-04-13 12:58:26 +02:00
truncate.c mm/thp: unmap_mapping_page() to fix THP truncate_cleanup_page() 2021-06-30 08:47:27 -04:00
usercopy.c mm/usercopy: return 1 from hardened_usercopy __setup() handler 2022-04-08 14:40:43 +02:00
userfaultfd.c userfaultfd: fix mmap_changing checking in mfill_atomic_hugetlb 2024-03-01 13:16:43 +01:00
util.c mm: vmalloc: introduce array allocation functions 2024-02-23 08:41:55 +01:00
vmacache.c kernel: better document the use_mm/unuse_mm API contract 2020-06-10 19:14:18 -07:00
vmalloc.c mm: add a call to flush_cache_vmap() in vmap_pfn() 2023-08-30 16:23:14 +02:00
vmpressure.c
vmscan.c mm, vmscan: prevent infinite loop for costly GFP_NOIO | __GFP_RETRY_MAYFAIL allocations 2024-04-13 12:59:22 +02:00
vmstat.c arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2022-05-15 20:00:09 +02:00
workingset.c XArray updates for 5.9 2020-10-20 14:39:37 -07:00
z3fold.c mm/z3fold: use release_z3fold_page_locked() to release locked z3fold page 2021-07-14 16:56:51 +02:00
zbud.c mm/zbud: remove redundant initialization 2020-10-13 18:38:34 -07:00
zpool.c mm/zpool.c: delete duplicated word and fix grammar 2020-08-12 10:57:58 -07:00
zsmalloc.c zsmalloc: fix races between asynchronous zspage free and page migration 2022-06-06 08:42:43 +02:00
zswap.c mm/zswap: allow setting default status, compressor and allocator in Kconfig 2020-04-07 10:43:41 -07:00