linux_dsm_epyc7002/mm
Vlastimil Babka 32a6f409b6 mm, slub: remove runtime allocation order changes
SLUB allows runtime changing of page allocation order by writing into the
/sys/kernel/slab/<cache>/order file.  Jann has reported [1] that this
interface allows the order to be set too small, leading to crashes.

While it's possible to fix the immediate issue, closer inspection reveals
potential races.  Storing the new order calls calculate_sizes() which
non-atomically updates a lot of kmem_cache fields while the cache is still
in use.  Unexpected behavior might occur even if the fields are set to the
same value as they were.

This could be fixed by splitting out the part of calculate_sizes() that
depends on forced_order, so that we only update kmem_cache.oo field.  This
could still race with init_cache_random_seq(), shuffle_freelist(),
allocate_slab().  Perhaps it's possible to audit and e.g.  add some
READ_ONCE/WRITE_ONCE accesses, it might be easier just to remove the
runtime order changes, which is what this patch does.  If there are valid
usecases for per-cache order setting, we could e.g.  extend the boot
parameters to do that.

[1] https://lore.kernel.org/r/CAG48ez31PP--h6_FzVyfJ4H86QYczAFPdxtJHUEEan+7VJETAQ@mail.gmail.com

Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Link: http://lkml.kernel.org/r/20200610163135.17364-4-vbabka@suse.cz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:22 -07:00
..
kasan mm: remove __ARCH_HAS_5LEVEL_HACK and include/asm-generic/5level-fixup.h 2020-06-04 19:06:21 -07:00
backing-dev.c writeback: remove struct bdi_writeback_congested 2020-07-08 17:05:53 -06:00
balloon_compaction.c mm/balloon_compaction: suppress allocation warnings 2019-09-04 07:42:01 -04:00
cleancache.c Driver Core and debugfs changes for 5.3-rc1 2019-07-12 12:24:03 -07:00
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.c: use exact_nid true to fix possible per-numa cma leak 2020-07-03 16:15:25 -07:00
cma.h debugfs: make sure we can remove u32_array files cleanly 2020-07-10 13:54:00 -07:00
compaction.c mm, compaction: make capture control handling safe wrt interrupts 2020-06-26 00:27:36 -07:00
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_vm_pgtable.c mm/debug_vm_pgtable: Remove uninitialized_var() usage 2020-07-16 12:32:26 -07:00
debug.c maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
dmapool.c mm/dmapool.c: micro-optimisation remove unnecessary branch 2020-04-07 10:43:42 -07:00
early_ioremap.c mm/early_ioremap.c: use %pa to print resource_size_t variables 2020-01-31 10:30:38 -08:00
fadvise.c mm: return void from various readahead functions 2020-06-02 10:59:06 -07:00
failslab.c mm/failslab.c: by default, do not fail allocations with direct reclaim only 2019-07-12 11:05:43 -07:00
filemap.c for-5.9/io_uring-20200802 2020-08-03 13:01:22 -07:00
frame_vector.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
frontswap.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
gup_benchmark.c mm/gup_benchmark: support pin_user_pages() and related calls 2020-04-02 09:35:27 -07:00
gup.c mm: Allow arches to provide ptep_get() 2020-06-20 22:14:53 +10:00
highmem.c mm, x86/mm: Untangle address space layout definitions from basic pgtable type definitions 2019-12-10 10:12:55 +01:00
hmm.c mm/hmm: provide the page mapping order in hmm_range_fault() 2020-07-10 16:24:28 -03:00
huge_memory.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
hugetlb_cgroup.c mm: use fallthrough; 2020-04-07 10:43:41 -07:00
hugetlb.c mm/hugetlb: avoid hardcoding while checking if cma is enabled 2020-07-24 12:42:41 -07:00
hwpoison-inject.c mm/hwpoison-inject: use DEFINE_DEBUGFS_ATTRIBUTE to define debugfs fops 2019-12-01 12:59:09 -08:00
init-mm.c mmap locking API: add MMAP_LOCK_INITIALIZER 2020-06-09 09:39:14 -07:00
internal.h mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
interval_tree.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 248 2019-06-19 17:09:08 +02:00
Kconfig docs: move nommu-mmap.txt to admin-guide and rename to ReST 2020-06-26 11:33:35 -06:00
Kconfig.debug treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
khugepaged.c khugepaged: fix null-pointer dereference due to race 2020-07-24 12:42:41 -07:00
kmemleak-test.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333 2019-06-05 17:37:06 +02:00
kmemleak.c mm/kmemleak.c: use address-of operator on section symbols 2020-04-02 09:35:26 -07:00
ksm.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
list_lru.c mm/list_lru.c: Rename kvfree_rcu() to local variant 2020-06-29 11:59:25 -07:00
maccess.c maccess: rename probe_user_{read,write} to copy_{from,to}_user_nofault 2020-06-17 10:57:41 -07:00
madvise.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
Makefile The Kernel Concurrency Sanitizer (KCSAN) 2020-06-11 18:55:43 -07:00
mapping_dirty_helpers.c mm/mapping_dirty_helpers: update huge page-table entry callbacks 2020-04-02 09:35:29 -07:00
memblock.c mm/memblock: expose only miminal interface to add/walk physmem 2020-07-10 15:08:09 +02:00
memcontrol.c Remove uninitialized_var() macro for v5.9-rc1 2020-08-04 13:49:43 -07:00
memfd.c mm: page cache: store only head pages in i_pages 2019-09-24 15:54:08 -07:00
memory_hotplug.c mm/memory_hotplug.c: fix false softlockup during pfn range removal 2020-06-26 00:27:38 -07:00
memory-failure.c mm/memory-failure: send SIGBUS(BUS_MCEERR_AR) only to current thread 2020-06-11 18:17:47 -07:00
memory.c Remove uninitialized_var() macro for v5.9-rc1 2020-08-04 13:49:43 -07:00
mempolicy.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
mempool.c docs/core-api/mm: fix return value descriptions in mm/ 2019-03-05 21:07:20 -08:00
memremap.c mm/memremap: set caching mode for PCI P2PDMA memory to WC 2020-04-10 15:36:21 -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/migrate: fix migrate_pgmap_owner w/o CONFIG_MMU_NOTIFIER 2020-08-07 11:33:21 -07:00
mincore.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
mlock.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
mm_init.c mm/mm_init.c: report kasan-tag information stored in page->flags 2020-06-02 10:59:12 -07:00
mmap.c Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu 2020-07-31 00:15:53 +02:00
mmu_gather.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
mmu_notifier.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
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 mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
mremap.c mm: document warning in move_normal_pmd() and make it warn only once 2020-07-13 11:37:39 -07:00
msync.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
nommu.c It's been a busy cycle for documentation - hopefully the busiest for a 2020-08-04 22:47:54 -07:00
oom_kill.c kernel: better document the use_mm/unuse_mm API contract 2020-06-10 19:14:18 -07:00
page_alloc.c Remove uninitialized_var() macro for v5.9-rc1 2020-08-04 13:49:43 -07:00
page_counter.c mm, memcg: prevent memory.min load/store tearing 2020-04-02 09:35:29 -07:00
page_ext.c mm/page_ext.c: drop pfn_present() check when onlining 2020-04-07 10:43:40 -07:00
page_idle.c mm/page_idle.c: skip offline pages 2020-06-08 11:05:55 -07:00
page_io.c block: move bio_associate_blkg_from_page to mm/page_io.c 2020-06-29 09:09:08 -06:00
page_isolation.c mm: Allow to offline unmovable PageOffline() pages via MEM_GOING_OFFLINE 2020-06-04 15:36:52 -04:00
page_owner.c mm: rename gfpflags_to_migratetype to gfp_migratetype for same convention 2020-06-03 20:09:45 -07:00
page_poison.c mm/page_poison.c: fix a typo in a comment 2019-09-24 15:54:08 -07:00
page_reporting.c mm/page_reporting: add budget limit on how many pages can be reported per pass 2020-04-07 10:43:39 -07:00
page_reporting.h mm: introduce include/linux/pgtable.h 2020-06-09 09:39:13 -07:00
page_vma_mapped.c mm/page_vma_mapped.c: explicitly compare pfn for normal, hugetlbfs and THP page 2020-01-31 10:30:38 -08:00
page-writeback.c mm/page-writeback: fix a typo in comment "effictive"->"effective" 2020-06-04 19:06:24 -07:00
pagewalk.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
percpu-internal.h percpu: convert chunk hints to be based on pcpu_block_md 2019-03-13 12:25:31 -07:00
percpu-km.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu-stats.c percpu: update copyright emails to dennis@kernel.org 2020-04-01 10:09:12 -07:00
percpu-vm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
pgtable-generic.c mm: introduce include/linux/pgtable.h 2020-06-09 09:39:13 -07:00
process_vm_access.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
ptdump.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
readahead.c mm: use memalloc_nofs_save in readahead path 2020-06-02 10:59:07 -07:00
rmap.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
rodata_test.c maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
shmem.c vfs/xattr: mm/shmem: kernfs: release simple xattr entry in a right way 2020-07-24 12:42:41 -07:00
shuffle.c mm/shuffle: don't move pages between zones and don't read garbage memmaps 2020-08-07 11:33:21 -07:00
shuffle.h mm: adjust shuffle code to allow for future coalescing 2020-04-07 10:43:38 -07:00
slab_common.c mm, slab: check GFP_SLAB_BUG_MASK before alloc_pages in kmalloc_order 2020-08-07 11:33:22 -07:00
slab.c mm/slab.c: update outdated kmem_list3 in a comment 2020-08-07 11:33:22 -07:00
slab.h mm, slab: check GFP_SLAB_BUG_MASK before alloc_pages in kmalloc_order 2020-08-07 11:33:22 -07:00
slob.c mm/sl[uo]b: export __kmalloc_track(_node)_caller 2020-03-26 14:45:51 +01:00
slub.c mm, slub: remove runtime allocation order changes 2020-08-07 11:33:22 -07:00
sparse-vmemmap.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sparse.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
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: assign|reset cache slot by value directly 2020-04-02 09:35:27 -07:00
swap_state.c mm: fix swap cache node allocation mask 2020-06-26 00:27:37 -07:00
swap.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
swapfile.c block: remove the bd_queue field from struct block_device 2020-07-01 08:08:20 -06:00
truncate.c mm/thp: allow dropping THP from page cache 2019-10-19 06:32:33 -04:00
usercopy.c usercopy: Avoid HIGHMEM pfn warning 2019-09-17 15:20:17 -07:00
userfaultfd.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
util.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
vmacache.c kernel: better document the use_mm/unuse_mm API contract 2020-06-10 19:14:18 -07:00
vmalloc.c mm: remove vmalloc_exec 2020-06-26 00:27:38 -07:00
vmpressure.c mm: vmpressure: use mem_cgroup_is_root API 2020-04-02 09:35:31 -07:00
vmscan.c mm: workingset: age nonresident information alongside anonymous pages 2020-06-26 00:27:37 -07:00
vmstat.c mm/vmstat.c: convert to use DEFINE_SEQ_ATTRIBUTE macro 2020-06-04 19:06:26 -07:00
workingset.c mm: workingset: age nonresident information alongside anonymous pages 2020-06-26 00:27:37 -07:00
z3fold.c mm/z3fold: silence kmemleak false positives of slots 2020-05-28 11:35:40 -07:00
zbud.c mm: use false for bool variable 2020-06-04 19:06:24 -07:00
zpool.c zpool: add malloc_support_movable to zpool_driver 2019-09-24 15:54:12 -07:00
zsmalloc.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
zswap.c mm/zswap: allow setting default status, compressor and allocator in Kconfig 2020-04-07 10:43:41 -07:00