linux/mm
Miaohe Lin 52ccdde16b mm/hugetlb: fix DEBUG_LOCKS_WARN_ON(1) when dissolve_free_hugetlb_folio()
When I did memory failure tests recently, below warning occurs:

DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 8 PID: 1011 at kernel/locking/lockdep.c:232 __lock_acquire+0xccb/0x1ca0
Modules linked in: mce_inject hwpoison_inject
CPU: 8 PID: 1011 Comm: bash Kdump: loaded Not tainted 6.9.0-rc3-next-20240410-00012-gdb69f219f4be #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
RIP: 0010:__lock_acquire+0xccb/0x1ca0
RSP: 0018:ffffa7a1c7fe3bd0 EFLAGS: 00000082
RAX: 0000000000000000 RBX: eb851eb853975fcf RCX: ffffa1ce5fc1c9c8
RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffffa1ce5fc1c9c0
RBP: ffffa1c6865d3280 R08: ffffffffb0f570a8 R09: 0000000000009ffb
R10: 0000000000000286 R11: ffffffffb0f2ad50 R12: ffffa1c6865d3d10
R13: ffffa1c6865d3c70 R14: 0000000000000000 R15: 0000000000000004
FS:  00007ff9f32aa740(0000) GS:ffffa1ce5fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff9f3134ba0 CR3: 00000008484e4000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0xbe/0x2d0
 _raw_spin_lock_irqsave+0x3a/0x60
 hugepage_subpool_put_pages.part.0+0xe/0xc0
 free_huge_folio+0x253/0x3f0
 dissolve_free_huge_page+0x147/0x210
 __page_handle_poison+0x9/0x70
 memory_failure+0x4e6/0x8c0
 hard_offline_page_store+0x55/0xa0
 kernfs_fop_write_iter+0x12c/0x1d0
 vfs_write+0x380/0x540
 ksys_write+0x64/0xe0
 do_syscall_64+0xbc/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff9f3114887
RSP: 002b:00007ffecbacb458 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007ff9f3114887
RDX: 000000000000000c RSI: 0000564494164e10 RDI: 0000000000000001
RBP: 0000564494164e10 R08: 00007ff9f31d1460 R09: 000000007fffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c
R13: 00007ff9f321b780 R14: 00007ff9f3217600 R15: 00007ff9f3216a00
 </TASK>
Kernel panic - not syncing: kernel: panic_on_warn set ...
CPU: 8 PID: 1011 Comm: bash Kdump: loaded Not tainted 6.9.0-rc3-next-20240410-00012-gdb69f219f4be #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 panic+0x326/0x350
 check_panic_on_warn+0x4f/0x50
 __warn+0x98/0x190
 report_bug+0x18e/0x1a0
 handle_bug+0x3d/0x70
 exc_invalid_op+0x18/0x70
 asm_exc_invalid_op+0x1a/0x20
RIP: 0010:__lock_acquire+0xccb/0x1ca0
RSP: 0018:ffffa7a1c7fe3bd0 EFLAGS: 00000082
RAX: 0000000000000000 RBX: eb851eb853975fcf RCX: ffffa1ce5fc1c9c8
RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffffa1ce5fc1c9c0
RBP: ffffa1c6865d3280 R08: ffffffffb0f570a8 R09: 0000000000009ffb
R10: 0000000000000286 R11: ffffffffb0f2ad50 R12: ffffa1c6865d3d10
R13: ffffa1c6865d3c70 R14: 0000000000000000 R15: 0000000000000004
 lock_acquire+0xbe/0x2d0
 _raw_spin_lock_irqsave+0x3a/0x60
 hugepage_subpool_put_pages.part.0+0xe/0xc0
 free_huge_folio+0x253/0x3f0
 dissolve_free_huge_page+0x147/0x210
 __page_handle_poison+0x9/0x70
 memory_failure+0x4e6/0x8c0
 hard_offline_page_store+0x55/0xa0
 kernfs_fop_write_iter+0x12c/0x1d0
 vfs_write+0x380/0x540
 ksys_write+0x64/0xe0
 do_syscall_64+0xbc/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff9f3114887
RSP: 002b:00007ffecbacb458 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007ff9f3114887
RDX: 000000000000000c RSI: 0000564494164e10 RDI: 0000000000000001
RBP: 0000564494164e10 R08: 00007ff9f31d1460 R09: 000000007fffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c
R13: 00007ff9f321b780 R14: 00007ff9f3217600 R15: 00007ff9f3216a00
 </TASK>

After git bisecting and digging into the code, I believe the root cause is
that _deferred_list field of folio is unioned with _hugetlb_subpool field.
In __update_and_free_hugetlb_folio(), folio->_deferred_list is
initialized leading to corrupted folio->_hugetlb_subpool when folio is
hugetlb.  Later free_huge_folio() will use _hugetlb_subpool and above
warning happens.

But it is assumed hugetlb flag must have been cleared when calling
folio_put() in update_and_free_hugetlb_folio().  This assumption is broken
due to below race:

CPU1					CPU2
dissolve_free_huge_page			update_and_free_pages_bulk
 update_and_free_hugetlb_folio		 hugetlb_vmemmap_restore_folios
					  folio_clear_hugetlb_vmemmap_optimized
  clear_flag = folio_test_hugetlb_vmemmap_optimized
  if (clear_flag) <-- False, it's already cleared.
   __folio_clear_hugetlb(folio) <-- Hugetlb is not cleared.
  folio_put
   free_huge_folio <-- free_the_page is expected.
					 list_for_each_entry()
					  __folio_clear_hugetlb <-- Too late.

Fix this issue by checking whether folio is hugetlb directly instead of
checking clear_flag to close the race window.

Link: https://lkml.kernel.org/r/20240419085819.1901645-1-linmiaohe@huawei.com
Fixes: 32c877191e ("hugetlb: do not clear hugetlb dtor until allocating vmemmap")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25 10:07:27 -07:00
..
damon
kasan
kfence
kmsan
Kconfig Kbuild updates for v6.9 2024-03-21 14:41:00 -07:00
Kconfig.debug
Makefile kbuild: make -Woverride-init warnings more consistent 2024-03-31 11:32:26 +09:00
backing-dev.c
balloon_compaction.c
bootmem_info.c
cma.c
cma.h
cma_debug.c
cma_sysfs.c
compaction.c
debug.c
debug_page_alloc.c
debug_page_ref.c
debug_vm_pgtable.c
dmapool.c
dmapool_test.c
early_ioremap.c
fadvise.c
fail_page_alloc.c
failslab.c
filemap.c mm: cachestat: fix two shmem bugs 2024-03-26 11:07:20 -07:00
folio-compat.c
gup.c mm/madvise: make MADV_POPULATE_(READ|WRITE) handle VM_FAULT_RETRY properly 2024-04-16 15:39:48 -07:00
gup_test.c
gup_test.h
highmem.c
hmm.c
huge_memory.c userfaultfd: change src_folio after ensuring it's unpinned in UFFDIO_MOVE 2024-04-16 15:39:48 -07:00
hugetlb.c mm/hugetlb: fix DEBUG_LOCKS_WARN_ON(1) when dissolve_free_hugetlb_folio() 2024-04-25 10:07:27 -07:00
hugetlb_cgroup.c
hugetlb_vmemmap.c
hugetlb_vmemmap.h
hwpoison-inject.c
init-mm.c
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
khugepaged.c
kmemleak.c
ksm.c
list_lru.c
maccess.c
madvise.c mm/madvise: make MADV_POPULATE_(READ|WRITE) handle VM_FAULT_RETRY properly 2024-04-16 15:39:48 -07:00
mapping_dirty_helpers.c
memblock.c
memcontrol.c
memfd.c
memory-failure.c mm/memory-failure: fix deadlock when hugetlb_optimize_vmemmap is enabled 2024-04-16 15:39:50 -07:00
memory-tiers.c
memory.c x86/mm/pat: fix VM_PAT handling in COW mappings 2024-04-05 11:21:31 -07:00
memory_hotplug.c
mempolicy.c
mempool.c
memremap.c
memtest.c
migrate.c
migrate_device.c
mincore.c
mlock.c
mm_init.c
mm_slot.h
mmap.c RISC-V Patches for the 6.9 Merge Window 2024-03-22 10:41:13 -07:00
mmap_lock.c
mmu_gather.c
mmu_notifier.c
mmzone.c
mprotect.c
mremap.c
msync.c
nommu.c
oom_kill.c
page-writeback.c
page_alloc.c
page_counter.c
page_ext.c
page_idle.c
page_io.c
page_isolation.c
page_owner.c mm,page_owner: defer enablement of static branch 2024-04-16 15:39:51 -07:00
page_poison.c
page_reporting.c
page_reporting.h
page_table_check.c
page_vma_mapped.c
pagewalk.c
percpu-internal.h
percpu-km.c
percpu-stats.c
percpu-vm.c
percpu.c
pgalloc-track.h
pgtable-generic.c
process_vm_access.c
ptdump.c
readahead.c
rmap.c
rodata_test.c
secretmem.c
shmem.c mm/shmem: inline shmem_is_huge() for disabled transparent hugepages 2024-04-16 15:39:51 -07:00
shmem_quota.c tmpfs: fix race on handling dquot rbtree 2024-03-26 11:07:23 -07:00
show_mem.c
shrinker.c
shrinker_debug.c
shuffle.c
shuffle.h
slab.h
slab_common.c
slub.c
sparse-vmemmap.c
sparse.c
swap.c
swap.h
swap_cgroup.c
swap_slots.c
swap_state.c
swapfile.c
truncate.c
usercopy.c
userfaultfd.c userfaultfd: fix deadlock warning when locking src and dst VMAs 2024-03-26 11:07:23 -07:00
util.c
vmalloc.c mm: vmalloc: fix lockdep warning 2024-04-05 11:21:30 -07:00
vmpressure.c
vmscan.c
vmstat.c
workingset.c
z3fold.c
zbud.c
zpool.c
zsmalloc.c
zswap.c mm: zswap: fix shrinker NULL crash with cgroup_disable=memory 2024-04-24 19:34:26 -07:00