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BUG: KCSAN: data-race in __filemap_remove_folio / folio_mapping

write to 0xffffea0004deeb18 of 8 bytes by task 20727 on cpu 1:
 page_cache_delete mm/filemap.c:145 [inline]
 __filemap_remove_folio+0x201/0x2e0 mm/filemap.c:227
 filemap_remove_folio+0x6d/0x1d0 mm/filemap.c:257
 truncate_inode_folio+0x42/0x50 mm/truncate.c:176
 shmem_undo_range+0x27f/0xb60 mm/shmem.c:1145
 shmem_fallocate+0x84e/0x8f0 mm/shmem.c:3708
 vfs_fallocate+0x3ac/0x400 fs/open.c:338
 ksys_fallocate fs/open.c:362 [inline]
 __do_sys_fallocate fs/open.c:367 [inline]
 __se_sys_fallocate fs/open.c:365 [inline]
 __x64_sys_fallocate+0x7a/0xd0 fs/open.c:365
 x64_sys_call+0x298e/0x3020 arch/x86/include/generated/asm/syscalls_64.h:286
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffea0004deeb18 of 8 bytes by task 20728 on cpu 0:
 folio_mapping+0xa1/0xe0 mm/util.c:732
 folio_evictable mm/internal.h:575 [inline]
 move_folios_to_lru+0x1f6/0x810 mm/vmscan.c:1882
 evict_folios+0x29ce/0x2d80 mm/vmscan.c:4865
 try_to_shrink_lruvec+0x7c5/0xb10 mm/vmscan.c:4983
 lru_gen_shrink_lruvec mm/vmscan.c:5128 [inline]
 shrink_lruvec+0x25e/0x1b60 mm/vmscan.c:5888
 shrink_node_memcgs mm/vmscan.c:6127 [inline]
 shrink_node+0x69d/0x20f0 mm/vmscan.c:6171
 shrink_zones mm/vmscan.c:6410 [inline]
 do_try_to_free_pages+0x408/0xc90 mm/vmscan.c:6472
 try_to_free_mem_cgroup_pages+0x201/0x420 mm/vmscan.c:6794
 try_charge_memcg+0x375/0xa00 mm/memcontrol.c:2655
 obj_cgroup_charge_pages mm/memcontrol.c:3097 [inline]
 __memcg_kmem_charge_page+0x199/0x3a0 mm/memcontrol.c:3141
 __alloc_frozen_pages_noprof+0x18a/0x350 mm/page_alloc.c:5321
 alloc_pages_mpol+0xa9/0x1d0 mm/mempolicy.c:2490
 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline]
 alloc_pages_noprof+0x8f/0x140 mm/mempolicy.c:2581
 vm_area_alloc_pages mm/vmalloc.c:3742 [inline]
 __vmalloc_area_node mm/vmalloc.c:3892 [inline]
 __vmalloc_node_range_noprof+0xae9/0x11e0 mm/vmalloc.c:4082
 __kvmalloc_node_noprof+0x3a0/0x590 mm/slub.c:6961
 futex_hash_allocate+0x192/0x920 kernel/futex/core.c:1823
 futex_hash_prctl+0xd8/0xf0 kernel/futex/core.c:1995
 __do_sys_prctl kernel/sys.c:2885 [inline]
 __se_sys_prctl+0x4f4/0x13b0 kernel/sys.c:2534
 __x64_sys_prctl+0x67/0x80 kernel/sys.c:2534
 x64_sys_call+0x2533/0x3020 arch/x86/include/generated/asm/syscalls_64.h:158
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff88812e4c7590 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 20728 Comm: syz.1.4453 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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