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BUG: KCSAN: data-race in __filemap_remove_folio / folio_mapping

write to 0xffffea0004131ad8 of 8 bytes by task 5430 on cpu 0:
 page_cache_delete mm/filemap.c:144 [inline]
 __filemap_remove_folio+0x1a5/0x2a0 mm/filemap.c:224
 filemap_remove_folio+0x6d/0x1d0 mm/filemap.c:253
 truncate_inode_folio+0x42/0x50 mm/truncate.c:176
 shmem_undo_range+0x244/0xa80 mm/shmem.c:1121
 shmem_fallocate+0x799/0x840 mm/shmem.c:3753
 vfs_fallocate+0x410/0x450 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+0x2b88/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:286
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffea0004131ad8 of 8 bytes by task 5426 on cpu 1:
 folio_mapping+0xa1/0x120 mm/util.c:701
 folio_evictable mm/internal.h:475 [inline]
 move_folios_to_lru+0x132/0x6a0 mm/vmscan.c:1918
 evict_folios+0x300b/0x33d0 mm/vmscan.c:4728
 try_to_shrink_lruvec+0x45a/0x7e0 mm/vmscan.c:4859
 lru_gen_shrink_lruvec mm/vmscan.c:5008 [inline]
 shrink_lruvec+0x22e/0x1a40 mm/vmscan.c:5753
 shrink_node_memcgs mm/vmscan.c:5989 [inline]
 shrink_node+0x686/0x2110 mm/vmscan.c:6030
 shrink_zones mm/vmscan.c:6274 [inline]
 do_try_to_free_pages+0x3f6/0xcd0 mm/vmscan.c:6336
 try_to_free_mem_cgroup_pages+0x1ab/0x410 mm/vmscan.c:6664
 try_charge_memcg+0x3ab/0x870 mm/memcontrol.c:2302
 try_charge mm/memcontrol.c:2444 [inline]
 charge_memcg+0x51/0xc0 mm/memcontrol.c:4590
 __mem_cgroup_charge+0x28/0xb0 mm/memcontrol.c:4607
 mem_cgroup_charge include/linux/memcontrol.h:642 [inline]
 filemap_add_folio+0x4e/0x1b0 mm/filemap.c:964
 page_cache_ra_unbounded+0x1f3/0x380 mm/readahead.c:275
 do_page_cache_ra mm/readahead.c:327 [inline]
 page_cache_ra_order+0x102/0x120 mm/readahead.c:532
 do_sync_mmap_readahead+0x249/0x280 mm/filemap.c:3262
 filemap_fault+0x311/0xb40 mm/filemap.c:3403
 __do_fault+0xb9/0x200 mm/memory.c:5098
 do_shared_fault mm/memory.c:5582 [inline]
 do_fault mm/memory.c:5656 [inline]
 do_pte_missing mm/memory.c:4160 [inline]
 handle_pte_fault mm/memory.c:5997 [inline]
 __handle_mm_fault mm/memory.c:6140 [inline]
 handle_mm_fault+0xeff/0x2ae0 mm/memory.c:6309
 do_user_addr_fault+0x636/0x1090 arch/x86/mm/fault.c:1337
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x54/0xc0 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

value changed: 0xffff88811a71b928 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5426 Comm: syz.4.689 Not tainted 6.15.0-rc7-syzkaller-00175-g0f8c0258bf04 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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