linux/mm
Harry Yoo (Oracle) 5b31044e64 mm/slab: return NULL early from kmalloc_nolock() in NMI on UP
On UP kernels (!CONFIG_SMP), spin_trylock() is a no-op that
unconditionally succeeds even when the lock is already held. As a
result, kmalloc_nolock() called from NMI context can re-enter the slab
allocator and acquire n->list_lock that the interrupted context is
already holding, corrupting slab state.

With CONFIG_DEBUG_SPINLOCK on UP, the following BUG is triggered with
the slub_kunit test module:

  BUG: spinlock trylock failure on UP on CPU#0, kunit_try_catch/243
  [...]
  Call Trace:
   <NMI>
   dump_stack_lvl+0x3f/0x60
   do_raw_spin_trylock+0x41/0x50
   _raw_spin_trylock+0x24/0x50
   get_from_partial_node+0x120/0x4d0
   ___slab_alloc+0x8a/0x4c0
   kmalloc_nolock_noprof+0x164/0x310
   [...]
   </NMI>

Fix this by returning NULL early when invoked from NMI on a UP kernel.

Link: https://lore.kernel.org/linux-mm/ad_cqe51pvr1WaDg@hyeyoo
Cc: stable@vger.kernel.org
Fixes: af92793e52 ("slab: Introduce kmalloc_nolock() and kfree_nolock().")
Signed-off-by: Harry Yoo (Oracle) <harry@kernel.org>
Link: https://patch.msgid.link/20260427-nolock-api-fix-v2-2-a6b83a92d9a4@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
2026-04-27 09:14:36 +02:00
..
damon mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
kasan kasan: fix bug type classification for SW_TAGS mode 2026-04-05 13:53:18 -07:00
kfence kfence: add kfence.fault parameter 2026-04-05 13:53:06 -07:00
kmsan Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
tests sparc/mm: export symbols for lazy_mmu_mode KUnit tests 2026-01-31 14:22:40 -08:00
backing-dev.c treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
balloon.c mm: rename CONFIG_BALLOON_COMPACTION to CONFIG_BALLOON_MIGRATION 2026-01-31 14:22:36 -08:00
bootmem_info.c mm/bootmem_info: avoid using sparse_decode_mem_map() 2026-04-05 13:53:32 -07:00
bpf_memcontrol.c bpf: Revert "bpf: drop KF_ACQUIRE flag on BPF kfunc bpf_get_root_mem_cgroup()" 2026-01-21 09:38:16 -08:00
cma_debug.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
cma_sysfs.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
cma.c mm/cma: move put_page_testzero() out of VM_WARN_ON in cma_release() 2026-03-04 09:44:22 -08:00
cma.h
compaction.c mm/compaction: fix low_pfn advance on isolating hugetlb 2025-09-28 11:51:29 -07:00
debug_page_alloc.c
debug_page_ref.c
debug_vm_pgtable.c mm/debug_vm_pgtable: replace WRITE_ONCE() with pxd_clear() 2026-04-05 13:53:11 -07:00
debug.c mm: constify __dump_folio() arguments 2025-11-20 13:43:57 -08:00
dmapool_test.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
dmapool.c
early_ioremap.c mm/early_ioremap: clean up the use of WARN() for debugging 2026-01-26 20:02:26 -08:00
execmem.c mm/execmem: make the populate and alloc atomic 2026-04-05 13:53:34 -07:00
fadvise.c mm/fadvise: validate offset in generic_fadvise 2026-04-05 13:52:53 -07:00
fail_page_alloc.c
failslab.c
filemap.c mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
folio-compat.c mm: add SPDX id lines to some mm source files 2026-02-06 15:47:16 -08:00
gup_test.c mm: add SPDX id lines to some mm source files 2026-02-06 15:47:16 -08:00
gup_test.h
gup.c folio_batch: rename pagevec.h to folio_batch.h 2026-04-05 13:53:07 -07:00
highmem.c mm/highmem: fix __kmap_to_page() build error 2026-01-31 14:22:38 -08:00
hmm.c mm/hmm: Indicate that HMM requires DMA coherency 2026-03-20 12:05:56 +01:00
huge_memory.c mm: fix deferred split queue races during migration 2026-04-05 13:53:47 -07:00
hugetlb_cgroup.c Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
hugetlb_cma.c mm: hugetlb_cma: mark hugetlb_cma{_only} as __ro_after_init 2026-01-31 14:22:43 -08:00
hugetlb_cma.h mm: hugetlb: allocate frozen pages for gigantic allocation 2026-01-26 20:02:28 -08:00
hugetlb_internal.h mm/hugetlb: extract sysctl into hugetlb_sysctl.c 2025-11-20 13:43:57 -08:00
hugetlb_sysctl.c mm, hugetlb: implement movable_gigantic_pages sysctl 2026-01-20 19:24:50 -08:00
hugetlb_sysfs.c mm/hugetlb: extract sysfs into hugetlb_sysfs.c 2025-11-20 13:43:57 -08:00
hugetlb_vmemmap.c mm/hugetlb: remove hugetlb_optimize_vmemmap_key static key 2026-04-05 13:53:09 -07:00
hugetlb_vmemmap.h
hugetlb.c mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
hwpoison-inject.c mm/hwpoison: decouple hwpoison_filter from mm/memory-failure.c 2025-09-21 14:22:21 -07:00
init-mm.c mm: rename cpu_bitmap field to flexible_array 2026-01-19 12:30:00 -08:00
internal.h mm: add mmap_action_simple_ioremap() 2026-04-05 13:53:43 -07:00
interval_tree.c mm/memory: simplify calculation in unmap_mapping_range_tree() 2026-04-05 13:53:13 -07:00
ioremap.c
Kconfig mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
Kconfig.debug mm: fix DEBUG_RODATA_TEST indentation in Kconfig 2025-11-29 10:41:09 -08:00
khugepaged.c mm/khugepaged: fix issue with tracking lock 2026-04-05 13:53:47 -07:00
kmemleak.c mm/kmemleak: use PF_KTHREAD flag to detect kernel threads 2026-04-05 13:53:02 -07:00
ksm.c mm: convert do_brk_flags() to use vma_flags_t 2026-04-05 13:53:40 -07:00
list_lru.c ttm/pool: port to list_lru. (v2) 2026-04-08 06:52:47 +10:00
maccess.c
madvise.c mm/vma: convert vma_modify_flags[_uffd]() to use vma_flags_t 2026-04-05 13:53:41 -07:00
Makefile mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
mapping_dirty_helpers.c mm/dirty: replace READ_ONCE() with pudp_get() 2025-11-16 17:27:58 -08:00
memblock.c memblock: Permit existing reserved regions to be marked RSRV_KERN 2026-04-09 17:14:36 +02:00
memcontrol-v1.c memcg: consolidate private id refcount get/put helpers 2026-04-05 13:53:00 -07:00
memcontrol-v1.h memcg: consolidate private id refcount get/put helpers 2026-04-05 13:53:00 -07:00
memcontrol.c mm/memcontrol: fix reclaim_options leak in try_charge_memcg() 2026-04-05 13:53:36 -07:00
memfd_luo.c mm: memfd_luo: preserve file seals 2026-04-05 13:53:00 -07:00
memfd.c memfd: export memfd_{add,get}_seals() 2026-04-05 13:53:00 -07:00
memory_hotplug.c mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
memory-failure.c treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
memory-tiers.c mm: introduce CONFIG_NUMA_MIGRATION and simplify CONFIG_MIGRATION 2026-04-05 13:53:33 -07:00
memory.c mm: on remap assert that input range within the proposed VMA 2026-04-05 13:53:45 -07:00
mempolicy.c mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
mempool.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
memremap.c mm/zone_device: reinitialize large zone device private folios 2026-01-26 19:03:48 -08:00
memtest.c mm/memtest: add underflow detection for size calculation 2026-01-09 11:53:51 +02:00
migrate_device.c mm/migrate_device: document folio_get requirement before frozen PMD split 2026-04-05 13:53:19 -07:00
migrate.c mm: fix deferred split queue races during migration 2026-04-05 13:53:47 -07:00
mincore.c mm: replace remaining pte_to_swp_entry() with softleaf_from_pte() 2025-11-24 15:08:52 -08:00
mlock.c mm/vma: convert vma_modify_flags[_uffd]() to use vma_flags_t 2026-04-05 13:53:41 -07:00
mm_init.c mm: mark early-init static variables with __meminitdata 2026-04-05 13:53:34 -07:00
mm_slot.h
mmap_lock.c mm/vma: improve and document __is_vma_write_locked() 2026-01-31 14:22:51 -08:00
mmap.c mm: convert do_brk_flags() to use vma_flags_t 2026-04-05 13:53:40 -07:00
mmu_gather.c mm/mmu_gather: replace IPI with synchronize_rcu() when batch allocation fails 2026-04-05 13:53:05 -07:00
mmu_notifier.c mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
mmzone.c mm: introduce memdesc_flags_t 2025-09-13 16:55:07 -07:00
mprotect.c mm: simplify VMA flag tests of excluded flags 2026-04-05 13:53:41 -07:00
mremap.c mm: convert do_brk_flags() to use vma_flags_t 2026-04-05 13:53:40 -07:00
mseal.c mm/vma: convert vma_modify_flags[_uffd]() to use vma_flags_t 2026-04-05 13:53:41 -07:00
msync.c
nommu.c mm: abstract reading sysctl_max_map_count, and READ_ONCE() 2026-04-05 13:53:28 -07:00
numa_emulation.c mm: numa,memblock: Use SZ_1M macro to denote bytes to MB conversion 2025-08-20 16:31:23 +03:00
numa_memblks.c memblock: numa_memblks: fix detection of NUMA node for CXL windows 2026-02-21 09:58:22 -08:00
numa.c
oom_kill.c mm/oom_kill.c: simpilfy rcu call with guard(rcu) 2026-04-05 13:53:17 -07:00
page_alloc.c mm/page_alloc: return NULL early from alloc_frozen_pages_nolock() in NMI on UP 2026-04-27 09:14:36 +02:00
page_counter.c
page_ext.c mm/page_ext: Add page_ext_get_from_phys() 2026-01-21 12:51:48 +01:00
page_frag_cache.c
page_idle.c mm/page_idle.c: remove redundant mmu notifier in aging code 2026-04-05 13:53:02 -07:00
page_io.c mm: update outdated comments for removed scan_swap_map_slots() 2026-04-05 13:53:35 -07:00
page_isolation.c mm: page_isolation: introduce page_is_unmovable() 2026-01-31 14:22:42 -08:00
page_owner.c treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
page_poison.c
page_reporting.c mm/page_reporting: change page_reporting_order to PAGE_REPORTING_ORDER_UNSPECIFIED 2026-04-05 13:53:17 -07:00
page_reporting.h
page_table_check.c mm: provide address parameter to p{te,md,ud}_user_accessible_page() 2026-01-26 20:02:35 -08:00
page_vma_mapped.c mm: centralize+fix comments about compound_mapcount() in new sync_with_folio_pmd_zap() 2026-04-05 13:53:03 -07:00
page-writeback.c mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
pagewalk.c mm/pagewalk: fix race between concurrent split and refault 2026-04-05 13:53:37 -07:00
percpu-internal.h
percpu-km.c mm/mm/percpu-km: drop nth_page() usage within single allocation 2025-09-21 14:22:04 -07:00
percpu-stats.c
percpu-vm.c kmsan: remove hard-coded GFP_KERNEL flags 2025-11-16 17:27:54 -08:00
percpu.c percpu: add double free check to pcpu_free_area() 2026-01-31 14:22:52 -08:00
pgalloc-track.h
pgtable-generic.c mm: change to return bool for pmdp_clear_flush_young() 2026-04-05 13:53:35 -07:00
process_vm_access.c
ptdump.c mm/ptdump: replace READ_ONCE() with standard page table accessors 2025-11-16 17:27:52 -08:00
readahead.c mm.git review status for linus..mm-stable 2026-02-12 11:32:37 -08:00
rmap.c mm/mglru: fix cgroup OOM during MGLRU state switching 2026-04-05 13:53:33 -07:00
rodata_test.c
secretmem.c mm: rename VMA flag helpers to be more readable 2026-04-05 13:53:18 -07:00
shmem_quota.c treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
shmem.c mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
show_mem.c mm: add gpu active/reclaim per-node stat counters (v2) 2026-04-08 06:52:47 +10:00
shrinker_debug.c memcg: rename mem_cgroup_ino() to mem_cgroup_id() 2026-01-26 20:02:25 -08:00
shrinker.c mm: do not allocate shrinker info with cgroup.memory=nokmem 2026-04-05 13:53:05 -07:00
shuffle.c
shuffle.h
slab_common.c Merge branch 'slab/for-7.0/sheaves' into slab/for-next 2026-02-10 09:10:00 +01:00
slab.h mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
slub.c mm/slab: return NULL early from kmalloc_nolock() in NMI on UP 2026-04-27 09:14:36 +02:00
sparse-vmemmap.c mm: mark early-init static variables with __meminitdata 2026-04-05 13:53:34 -07:00
sparse.c mm/sparse: move memory hotplug bits to sparse-vmemmap.c 2026-04-05 13:53:33 -07:00
swap_cgroup.c
swap_state.c mm/swap: fix swap cache memcg accounting 2026-04-05 13:53:37 -07:00
swap_table.h mm, swap: use the swap table to track the swap count 2026-04-05 13:52:59 -07:00
swap.c folio_batch: rename PAGEVEC_SIZE to FOLIO_BATCH_SIZE 2026-04-05 13:53:07 -07:00
swap.h mm, swap: no need to clear the shadow explicitly 2026-04-05 13:52:59 -07:00
swapfile.c mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
truncate.c folio_batch: rename PAGEVEC_SIZE to FOLIO_BATCH_SIZE 2026-04-05 13:53:07 -07:00
usercopy.c usercopy: Remove folio references from check_heap_object() 2025-11-13 11:01:08 +01:00
userfaultfd.c mm/vma: convert vma_modify_flags[_uffd]() to use vma_flags_t 2026-04-05 13:53:41 -07:00
util.c mm: add mmap_action_map_kernel_pages[_full]() 2026-04-05 13:53:45 -07:00
vma_exec.c mm: convert do_brk_flags() to use vma_flags_t 2026-04-05 13:53:40 -07:00
vma_init.c Summary of significant series in this pull request: 2025-10-02 18:18:33 -07:00
vma_internal.h mm: relocate the page table ceiling and floor definitions 2026-02-12 15:42:53 -08:00
vma.c mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
vma.h mm: allow handling of stacked mmap_prepare hooks in more drivers 2026-04-05 13:53:44 -07:00
vmalloc.c mm: vmalloc: update outdated comment for renamed vread() 2026-04-05 13:53:34 -07:00
vmpressure.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
vmscan.c mm: update outdated comments for removed scan_swap_map_slots() 2026-04-05 13:53:35 -07:00
vmstat.c mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
workingset.c mm/workingset: leave highest bits empty for anon shadow 2026-04-05 13:52:58 -07:00
zpdesc.h mm: zpdesc: minor naming and comment corrections 2025-09-21 14:21:59 -07:00
zsmalloc.c mm/zsmalloc: copy KMSAN metadata in zs_page_migrate() 2026-04-05 13:53:34 -07:00
zswap.c mm/zswap: remove SWP_SYNCHRONOUS_IO swapcache bypass workaround 2026-04-05 13:53:02 -07:00