linux/mm
Jan Kara 000099d716 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>
2024-07-11 12:51:17 +02:00
..
damon mm: madvise: pageout: ignore references rather than clearing young 2024-03-04 17:01:18 -08:00
kasan kasan: fix bad call to unpoison_slab_object 2024-07-05 09:38:04 +02:00
kfence KFENCE: cleanup kfence_guarded_alloc() after CONFIG_SLAB removal 2023-12-05 11:17:58 +01:00
kmsan kmsan: do not wipe out origin when doing partial unpoisoning 2024-06-16 13:51:06 +02:00
backing-dev.c vfs-6.9.misc 2024-03-11 09:38:17 -07:00
balloon_compaction.c
bootmem_info.c bootmem: use kmemleak_free_part_phys in put_page_bootmem 2023-10-25 16:47:13 -07:00
cma_debug.c
cma_sysfs.c mm/cma: add sysfs file 'release_pages_success' 2024-02-22 10:24:57 -08:00
cma.c mm/cma: drop incorrect alignment check in cma_init_reserved_mem 2024-06-16 13:51:07 +02:00
cma.h mm/cma: add sysfs file 'release_pages_success' 2024-02-22 10:24:57 -08:00
compaction.c - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
debug_page_alloc.c mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER 2024-01-08 15:27:15 -08:00
debug_page_ref.c
debug_vm_pgtable.c mm/debug_vm_pgtable: fix BUG_ON with pud advanced test 2024-02-23 17:27:13 -08:00
debug.c mm: make dump_page() take a const argument 2024-03-06 13:04:18 -08:00
dmapool_test.c
dmapool.c mm/mempool/dmapool: remove CONFIG_DEBUG_SLAB ifdefs 2023-12-05 11:17:58 +01:00
early_ioremap.c mm/early_ioremap.c: improve the execution efficiency of early_ioremap_setup() 2023-06-09 16:25:56 -07:00
fadvise.c mm: remove unnecessary pagevec includes 2023-06-23 16:59:31 -07:00
fail_page_alloc.c mm: page_alloc: split out FAIL_PAGE_ALLOC 2023-06-09 16:25:23 -07:00
failslab.c
filemap.c mm: cachestat: fix two shmem bugs 2024-03-26 11:07:20 -07:00
folio-compat.c mm: remove page_add_new_anon_rmap and lru_cache_add_inactive_or_unevictable 2023-12-29 11:58:27 -08:00
gup_test.c Merge mm-hotfixes-stable into mm-stable to pick up depended-upon changes. 2023-06-23 16:58:19 -07:00
gup_test.h
gup.c mm/madvise: make MADV_POPULATE_(READ|WRITE) handle VM_FAULT_RETRY properly 2024-04-16 15:39:48 -07:00
highmem.c x86/kexec: use pr_err() instead of kexec_dprintk() when an error occurs 2023-12-29 12:22:28 -08:00
hmm.c mm: enable page walking API to lock vmas during the walk 2023-08-21 13:07:20 -07:00
huge_memory.c mm: huge_memory: fix misused mapping_large_folio_support() for anon folios 2024-06-27 13:52:30 +02:00
hugetlb_cgroup.c mm, hugetlb: remove HUGETLB_CGROUP_MIN_ORDER 2023-10-18 14:34:17 -07:00
hugetlb_vmemmap.c mm: hugetlb_vmemmap: move mmap lock to vmemmap_remap_range() 2023-12-12 10:57:08 -08:00
hugetlb_vmemmap.h mm: hugetlb_vmemmap: fix reference to nonexistent file 2023-10-25 16:47:14 -07:00
hugetlb.c mm/hugetlb: pass correct order_per_bit to cma_declare_contiguous_nid 2024-06-16 13:51:07 +02:00
hwpoison-inject.c
init-mm.c mm: Deprecate pasid field 2023-12-12 10:11:32 +01:00
internal.h mm/madvise: make MADV_POPULATE_(READ|WRITE) handle VM_FAULT_RETRY properly 2024-04-16 15:39:48 -07:00
interval_tree.c
io-mapping.c
ioremap.c mm: ioremap: remove unneeded ioremap_allowed and iounmap_allowed 2023-08-18 10:12:36 -07:00
Kconfig Kbuild updates for v6.9 2024-03-21 14:41:00 -07:00
Kconfig.debug mm/slub: unify all sl[au]b parameters with "slab_$param" 2024-01-22 10:31:08 +01:00
khugepaged.c mm: convert free_swap_cache() to take a folio 2024-03-04 17:01:26 -08:00
kmemleak.c kmemleak: avoid RCU stalls when freeing metadata for per-CPU pointers 2023-12-12 10:57:07 -08:00
ksm.c mm/ksm: fix ksm_zero_pages accounting 2024-06-16 13:51:06 +02:00
list_lru.c mm/zswap: stop lru list shrinking when encounter warm region 2024-02-22 10:24:54 -08:00
maccess.c
madvise.c mm/madvise: make MADV_POPULATE_(READ|WRITE) handle VM_FAULT_RETRY properly 2024-04-16 15:39:48 -07:00
Makefile kbuild: make -Woverride-init warnings more consistent 2024-03-31 11:32:26 +09:00
mapping_dirty_helpers.c mm: fix clean_record_shared_mapping_range kernel-doc 2023-08-24 16:20:30 -07:00
memblock.c memblock: make memblock_set_node() also warn about use of MAX_NUMNODES 2024-06-21 14:40:29 +02:00
memcontrol.c mm: shmem: fix getting incorrect lruvec when replacing a shmem folio 2024-06-27 13:52:30 +02:00
memfd.c mm/memfd: refactor memfd_tag_pins() and memfd_wait_for_pins() 2024-03-04 17:01:21 -08:00
memory_hotplug.c mm/memory_hotplug: export mhp_supports_memmap_on_memory() 2024-02-22 10:24:40 -08:00
memory-failure.c mm/huge_memory: don't unpoison huge_zero_folio 2024-06-21 14:40:38 +02:00
memory-tiers.c mm/demotion: print demotion targets 2024-02-22 10:24:55 -08:00
memory.c mm/memory: don't require head page for do_set_pmd() 2024-07-05 09:38:05 +02:00
mempolicy.c mm/mempolicy: use a folio in do_mbind() 2024-03-06 13:04:18 -08:00
mempool.c mempool: kvmalloc pool 2024-03-13 18:38:13 -04:00
memremap.c mm: remove stale example from comment 2023-12-29 11:58:26 -08:00
memtest.c memtest: use {READ,WRITE}_ONCE in memory scanning 2024-03-13 12:12:21 -07:00
migrate_device.c mm: convert page_try_share_anon_rmap() to folio_try_share_anon_rmap_[pte|pmd]() 2023-12-29 11:58:56 -08:00
migrate.c merge mm-hotfixes-stable into mm-nonmm-stable to pick up stackdepot changes 2024-02-23 17:28:43 -08:00
mincore.c mm: enable page walking API to lock vmas during the walk 2023-08-21 13:07:20 -07:00
mlock.c mm: make folios_put() the basis of release_pages() 2024-03-04 17:01:22 -08:00
mm_init.c Author: Gang Li padata: dispatch works on 2024-03-06 13:04:17 -08:00
mm_slot.h
mmap_lock.c
mmap.c RISC-V Patches for the 6.9 Merge Window 2024-03-22 10:41:13 -07:00
mmu_gather.c mm/mmu_gather: improve cond_resched() handling with large folios and expensive page freeing 2024-02-22 15:27:17 -08:00
mmu_notifier.c mmu_notifiers: rename invalidate_range notifier 2023-08-18 10:12:41 -07:00
mmzone.c zswap: shrink zswap pool based on memory pressure 2023-12-12 10:57:02 -08:00
mprotect.c mprotect: use pfn_swap_entry_folio 2024-02-21 16:00:03 -08:00
mremap.c mm: abstract VMA merge and extend into vma_merge_extend() helper 2023-10-18 14:34:18 -07:00
msync.c
nommu.c mm/vmalloc: remove vmap_area_list 2024-02-23 17:48:19 -08:00
oom_kill.c mm: update mark_victim tracepoints fields 2024-03-04 17:01:16 -08:00
page_alloc.c mm/page_alloc: Separate THP PCP into movable and non-movable categories 2024-07-05 09:38:17 +02:00
page_counter.c
page_ext.c mm/page_ext: move functions around for minor cleanups to page_ext 2023-08-18 10:12:31 -07:00
page_idle.c
page_io.c zswap: memcontrol: implement zswap writeback disabling 2023-12-29 20:22:11 -08:00
page_isolation.c mm: add alloc_contig_migrate_range allocation statistics 2024-03-04 17:01:27 -08:00
page_owner.c mm,page_owner: don't remove __GFP_NOLOCKDEP in add_stack_record_to_list 2024-05-05 17:28:07 -07:00
page_poison.c mm/page_poison: replace kmap_atomic() with kmap_local_page() 2023-12-10 16:51:50 -08:00
page_reporting.c mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER 2024-01-08 15:27:15 -08:00
page_reporting.h
page_table_check.c mm/page_table_check: fix crash on ZONE_DEVICE 2024-06-27 13:52:30 +02:00
page_vma_mapped.c mm: thp: introduce multi-size THP sysfs interface 2023-12-20 14:48:12 -08:00
page-writeback.c Revert "mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again" 2024-07-11 12:51:17 +02:00
pagewalk.c mm: pagewalk: assert write mmap lock only for walking the user page tables 2023-12-10 16:51:53 -08:00
percpu-internal.h percpu-internal/pcpu_chunk: re-layout pcpu_chunk structure to reduce false sharing 2023-06-19 16:19:29 -07:00
percpu-km.c
percpu-stats.c
percpu-vm.c
percpu.c mm: Introduce flush_cache_vmap_early() 2023-12-14 00:23:17 -08:00
pgalloc-track.h
pgtable-generic.c mm: fix race between __split_huge_pmd_locked() and GUP-fast 2024-06-16 13:51:04 +02:00
process_vm_access.c mm: fix process_vm_rw page counts 2023-12-10 16:51:39 -08:00
ptdump.c mm: ptdump: add check_wx_pages debugfs attribute 2024-02-22 10:24:47 -08:00
readahead.c mm: use memalloc_nofs_save() in page_cache_ra_order() 2024-05-05 17:28:06 -07:00
rmap.c rmap: replace two calls to compound_order with folio_order 2024-02-22 15:27:20 -08:00
rodata_test.c
secretmem.c mm/secretmem: use a folio in secretmem_fault() 2023-08-21 13:38:02 -07:00
shmem_quota.c tmpfs: fix race on handling dquot rbtree 2024-03-26 11:07:23 -07:00
shmem.c mm: shmem: fix getting incorrect lruvec when replacing a shmem folio 2024-06-27 13:52:30 +02:00
show_mem.c mm, treewide: introduce NR_PAGE_ORDERS 2024-01-08 15:27:15 -08:00
shrinker_debug.c mm: shrinker: convert shrinker_rwsem to mutex 2023-10-04 10:32:26 -07:00
shrinker.c mm: shrinker: use kvzalloc_node() from expand_one_shrinker_info() 2024-01-05 09:58:32 -08:00
shuffle.c
shuffle.h mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER 2024-01-08 15:27:15 -08:00
slab_common.c - Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min 2024-03-14 18:03:09 -07:00
slab.h Merge branch 'slab/for-6.9/slab-flag-cleanups' into slab/for-linus 2024-03-12 10:16:56 +01:00
slub.c mm/slub: avoid zeroing outside-object freepointer for single free 2024-05-01 17:28:56 +02:00
sparse-vmemmap.c mm/vmemmap: allow architectures to override how vmemmap optimization works 2023-08-18 10:12:53 -07:00
sparse.c mm/memory_hotplug: introduce MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE notifiers 2024-02-21 16:00:01 -08:00
swap_cgroup.c
swap_slots.c mm/zswap: invalidate zswap entry when swap entry free 2024-02-22 10:24:54 -08:00
swap_state.c mm: convert free_swap_cache() to take a folio 2024-03-04 17:01:26 -08:00
swap.c mm: fix list corruption in put_pages_list 2024-03-12 13:07:16 -07:00
swap.h mm/swap: fix race when skipping swapcache 2024-02-20 14:20:48 -08:00
swapfile.c - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
truncate.c fs: convert error_remove_page to error_remove_folio 2023-12-10 16:51:42 -08:00
usercopy.c
userfaultfd.c mm/userfaultfd: Do not place zeropages when zeropages are disallowed 2024-05-30 09:44:07 +02:00
util.c - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
vmalloc.c mm: fix incorrect vbq reference in purge_fragmented_block 2024-07-05 09:38:04 +02:00
vmpressure.c eventfd: simplify eventfd_signal() 2023-11-28 14:08:38 +01:00
vmscan.c - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
vmstat.c mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER 2024-01-08 15:27:15 -08:00
workingset.c mm: move mapping_set_update out of <linux/swap.h> 2024-02-21 11:36:50 +05:30
z3fold.c mm/z3fold: fix the comment for __encode_handle() 2024-02-23 17:48:31 -08:00
zbud.c mm: zswap: remove shrink from zpool interface 2023-06-19 16:19:27 -07:00
zpool.c mm: zswap: remove shrink from zpool interface 2023-06-19 16:19:27 -07:00
zsmalloc.c mm/zsmalloc: don't need to reserve LSB in handle 2024-03-04 17:01:28 -08:00
zswap.c mm: zswap: fix shrinker NULL crash with cgroup_disable=memory 2024-04-24 19:34:26 -07:00