linux/mm
David Rientjes 469020eb5b mm, thp: fix defrag setting if newline is not used
commit f42f255265 upstream.

If thp defrag setting "defer" is used and a newline is *not* used when
writing to the sysfs file, this is interpreted as the "defer+madvise"
option.

This is because we do prefix matching and if five characters are written
without a newline, the current code ends up comparing to the first five
bytes of the "defer+madvise" option and using that instead.

Use the more appropriate sysfs_streq() that handles the trailing newline
for us.  Since this doubles as a nice cleanup, do it in enabled_store()
as well.

The current implementation relies on prefix matching: the number of
bytes compared is either the number of bytes written or the length of
the option being compared.  With a newline, "defer\n" does not match
"defer+"madvise"; without a newline, however, "defer" is considered to
match "defer+madvise" (prefix matching is only comparing the first five
bytes).  End result is that writing "defer" is broken unless it has an
additional trailing character.

This means that writing "madv" in the past would match and set
"madvise".  With strict checking, that no longer is the case but it is
unlikely anybody is currently doing this.

Link: http://lkml.kernel.org/r/alpine.DEB.2.21.2001171411020.56385@chino.kir.corp.google.com
Fixes: 21440d7eb9 ("mm, thp: add new defer+madvise defrag option")
Signed-off-by: David Rientjes <rientjes@google.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-05 16:42:23 +01:00
..
kasan kernel/memremap, kasan: make ZONE_DEVICE with work with KASAN 2018-08-17 16:20:30 -07:00
backing-dev.c writeback: synchronize sync(2) against cgroup writeback membership switches 2019-03-05 17:58:50 +01:00
balloon_compaction.c virtio_balloon: fix deadlock on OOM 2017-11-14 23:57:38 +02:00
bootmem.c docs/mm: bootmem: add overview documentation 2018-08-02 12:17:27 -06:00
cleancache.c mm: use octal not symbolic permissions 2018-06-15 07:55:25 +09:00
cma_debug.c mm/cma_debug.c: fix the break condition in cma_maxchunk_get() 2019-06-15 11:54:01 +02:00
cma.c mm/cma.c: fail if fixed declaration can't be honored 2019-08-06 19:06:51 +02:00
cma.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compaction.c mm/compaction.c: clear total_{migrate,free}_scanned before scanning a new zone 2019-10-05 13:10:13 +02:00
debug_page_ref.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debug.c mm: get rid of vmacache_flush_all() entirely 2018-09-13 15:18:04 -10:00
dmapool.c mm: use octal not symbolic permissions 2018-06-15 07:55:25 +09:00
early_ioremap.c mm/early_ioremap: Fix boot hang with earlyprintk=efi,keep 2017-12-11 14:54:44 +01:00
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 mm/filemap.c: don't initiate writeback if mapping has no dirty pages 2019-11-12 19:21:20 +01:00
frame_vector.c mm/frame_vector.c: release a semaphore in 'get_vaddr_frames()' 2017-12-14 16:00:48 -08:00
frontswap.c mm: use octal not symbolic permissions 2018-06-15 07:55:25 +09:00
gup_benchmark.c mm/gup_benchmark.c: prevent integer overflow in ioctl 2019-12-01 09:17:07 +01:00
gup.c mm/gup.c: remove some BUG_ONs from get_gate_page() 2019-07-31 07:27:08 +02:00
highmem.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hmm.c mm/memory_hotplug: shrink zones when offlining memory 2020-01-29 16:43:27 +01:00
huge_memory.c mm, thp: fix defrag setting if newline is not used 2020-03-05 16:42:23 +01:00
hugetlb_cgroup.c mm: hugetlb: switch to css_tryget() in hugetlb_cgroup_charge_cgroup() 2019-11-20 18:45:20 +01:00
hugetlb.c hugetlbfs: don't access uninitialized memmaps in pfn_range_valid_gigantic() 2019-10-29 09:19:59 +01:00
hwpoison-inject.c mm/memory_failure: Remove unused trapno from memory_failure 2018-01-23 12:17:42 -06:00
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 vmscan: return NODE_RECLAIM_NOSCAN in node_reclaim() when CONFIG_NUMA is n 2019-12-05 09:20:57 +01:00
interval_tree.c mm/interval_tree.c: use vma_pages() helper 2018-01-31 17:18:37 -08:00
Kconfig mm/hmm: select mmu notifier when selecting HMM 2019-06-15 11:54:00 +02:00
Kconfig.debug mm: clarify CONFIG_PAGE_POISONING and usage 2018-08-22 10:52:44 -07:00
khugepaged.c coredump: fix race condition between collapse_huge_page() and core dumping 2019-06-22 08:15:21 +02:00
kmemleak-test.c
kmemleak.c Revert "kmemleak: allow to coexist with fault injection" 2019-08-25 10:47:58 +02:00
ksm.c mm/ksm.c: don't WARN if page is still mapped in remove_stable_node() 2019-12-01 09:16:11 +01:00
list_lru.c mm/list_lru.c: fix memory leak in __memcg_init_list_lru_node 2019-06-19 08:17:59 +02:00
maccess.c mm: docs: fix parameter names mismatch 2018-02-06 18:32:48 -08:00
madvise.c mm: madvise(MADV_DODUMP): allow hugetlbfs pages 2018-10-05 16:32:05 -07:00
Makefile vfs: implement readahead(2) using POSIX_FADV_WILLNEED 2018-08-30 20:01:32 +02:00
memblock.c mm/page_alloc.c: deduplicate __memblock_free_early() and memblock_free() 2019-12-05 09:20:58 +01:00
memcontrol.c mm/memcontrol.c: lost css_put in memcg_expand_shrinker_maps() 2020-02-28 16:38:49 +01:00
memfd.c memfd: Use radix_tree_deref_slot_protected to avoid the warning. 2019-11-20 18:47:53 +01:00
memory_hotplug.c mm/memory_hotplug: fix remove_memory() lockdep splat 2020-02-11 04:33:56 -08:00
memory-failure.c mm/memory-failure: poison read receives SIGKILL instead of SIGBUS if mmaped more than once 2019-10-29 09:19:59 +01:00
memory.c mm, thp, proc: report THP eligibility for each vma 2019-12-17 20:35:45 +01:00
mempolicy.c mm/mempolicy.c: fix out of bounds write in mpol_parse_str() 2020-02-05 14:43:36 +00:00
mempool.c mm/mempool.c: add missing parameter description 2018-08-22 10:52:44 -07:00
memtest.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
migrate.c mm: move_pages: report the number of non-attempted pages 2020-02-11 04:33:56 -08:00
mincore.c mm/mincore.c: make mincore() more conservative 2019-05-22 07:37:40 +02:00
mlock.c mm/mlock.c: change count_mm_mlocked_page_nr return type 2019-07-10 09:53:40 +02:00
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 arm64: Revert support for execute-only user mappings 2020-01-09 10:19:03 +01:00
mmu_context.c
mmu_notifier.c mm/mmu_notifier: use hlist_add_head_rcu() 2019-07-31 07:27:08 +02:00
mmzone.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mprotect.c x86/speculation/l1tf: Disallow non privileged high MMIO PROT_NONE mappings 2018-06-20 19:10:01 +02:00
mremap.c mremap: properly flush TLB before releasing the page 2018-10-18 11:30:52 +02:00
msync.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nobootmem.c mm/memblock: add a name for memblock flags enumeration 2018-08-02 12:17:27 -06:00
nommu.c mm: use down_read_killable for locking mmap_sem in access_remote_vm 2019-07-31 07:27:09 +02:00
oom_kill.c memcg, oom: don't require __GFP_FS when invoking memcg OOM killer 2019-10-05 13:10:07 +02:00
page_alloc.c mm/page_alloc.c: fix uninitialized memmaps on a partially populated last section 2020-02-11 04:34:18 -08:00
page_counter.c memcg: introduce memory.min 2018-06-07 17:34:36 -07:00
page_ext.c mm/page_ext.c: fix an imbalance with kmemleak 2019-04-05 22:32:58 +02:00
page_idle.c mm/page_idle.c: fix oops because end_pfn is larger than max_pfn 2019-07-03 13:14:45 +02:00
page_io.c mm/page_io.c: do not free shared swap slots 2019-12-01 09:17:35 +01:00
page_isolation.c mm, migrate: remove reason argument from new_page_t 2018-04-11 10:28:32 -07:00
page_owner.c mm/page_owner: don't access uninitialized memmaps when reading /proc/pagetypeinfo 2019-10-29 09:19:58 +01:00
page_poison.c page_poison: play nicely with KASAN 2019-04-05 22:32:59 +02:00
page_vma_mapped.c mm/rmap: map_pte() was not handling private ZONE_DEVICE page properly 2018-11-13 11:08:46 -08:00
page-writeback.c mm/page-writeback.c: avoid potential division by zero in wb_min_max_ratio() 2020-01-23 08:21:31 +01:00
pagewalk.c mm: kernel-doc: add missing parameter descriptions 2018-04-05 21:36:27 -07:00
percpu-internal.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
percpu-km.c percpu: convert spin_lock_irq to spin_lock_irqsave. 2019-02-12 19:47:12 +01:00
percpu-stats.c treewide: Use array_size() in vmalloc() 2018-06-12 16:19:22 -07:00
percpu-vm.c percpu: allow select gfp to be passed to underlying allocators 2018-02-18 05:33:01 -08:00
percpu.c percpu: do not search past bitmap when allocating an area 2019-06-15 11:54:11 +02:00
pgtable-generic.c mm: do not lose dirty and accessed bits in pmdp_invalidate() 2018-01-31 17:18:38 -08:00
process_vm_access.c mm: docs: add blank lines to silence sphinx "Unexpected indentation" errors 2018-02-06 18:32:48 -08:00
quicklist.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
readahead.c vfs: implement readahead(2) using POSIX_FADV_WILLNEED 2018-08-30 20:01:32 +02:00
rmap.c mm/hmm: fix bad subpage pointer in try_to_unmap_one 2019-08-25 10:47:43 +02:00
rodata_test.c mm: fix RODATA_TEST failure "rodata_test: test data was not read only" 2017-10-03 17:54:24 -07:00
shmem.c mm/shmem.c: thp, shmem: fix conflict of above-47bit hint address and PMD alignment 2020-01-23 08:21:30 +01:00
slab_common.c mm: memcg/slab: call flush_memcg_workqueue() only if memcg workqueue is valid 2020-01-23 08:21:30 +01:00
slab.c mm/slab.c: fix an infinite loop in leaks_show() 2019-06-15 11:54:01 +02:00
slab.h mm: add support for kmem caches in DMA32 zone 2019-04-03 06:26:28 +02:00
slob.c slab: __GFP_ZERO is incompatible with a constructor 2018-06-07 17:34:34 -07:00
slub.c mm/slub: fix a deadlock in show_slab_objects() 2019-10-29 09:19:58 +01:00
sparse-vmemmap.c mm/sparse: delete old sparse_init and enable new one 2018-08-17 16:20:32 -07:00
sparse.c mm/memory_hotplug: remove "zone" parameter from sparse_remove_one_section 2020-01-29 16:43:26 +01:00
swap_cgroup.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
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 treewide: kvzalloc() -> kvcalloc() 2018-06-12 16:19:22 -07:00
swap.c mm/swap: fix release_pages() when releasing devmap pages 2019-07-31 07:27:03 +02:00
swapfile.c mm, swap: bounds check swap_info array accesses to avoid NULL derefs 2019-04-05 22:32:58 +02:00
truncate.c mm: cleancache: fix corruption on missed inode invalidation 2018-12-05 19:32:13 +01:00
usercopy.c usercopy: Avoid HIGHMEM pfn warning 2019-10-11 18:20:58 +02:00
userfaultfd.c hugetlb: use same fault hash key for shared and private mappings 2019-05-22 07:37:40 +02:00
util.c mm: page_mapped: don't assume compound page is huge or THP 2019-01-16 22:04:36 +01:00
vmacache.c mm: get rid of vmacache_flush_all() entirely 2018-09-13 15:18:04 -10:00
vmalloc.c mm/vmalloc: Sync unmappings in __purge_vmap_area_lazy() 2019-08-16 10:12:40 +02:00
vmpressure.c mm/vmpressure.c: fix a signedness bug in vmpressure_register_event() 2019-10-17 13:45:19 -07:00
vmscan.c mm/vmscan.c: don't round up scan size for online memory cgroup 2020-02-28 16:38:50 +01:00
vmstat.c mm/vmstat.c: fix NUMA statistics updates 2019-12-13 08:51:27 +01:00
workingset.c mm/list_lru: introduce list_lru_shrink_walk_irq() 2018-08-17 16:20:32 -07:00
z3fold.c z3fold: fix possible reclaim races 2018-12-01 09:37:33 +01:00
zbud.c mm: docs: fix parameter names mismatch 2018-02-06 18:32:48 -08:00
zpool.c mm/zpool.c: zpool_evictable: fix mismatch in parameter name and kernel-doc 2018-02-21 15:35:43 -08:00
zsmalloc.c mm/zsmalloc.c: fix the migrated zspage statistics. 2020-01-09 10:19:00 +01:00
zswap.c zswap: re-check zswap_is_full() after do zswap_shrink() 2018-07-26 19:38:03 -07:00