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BUG: KCSAN: data-race in __filemap_remove_folio / folio_mapping

write to 0xffffea0004d27ad8 of 8 bytes by task 31722 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:1155
 shmem_truncate_range mm/shmem.c:1287 [inline]
 shmem_evict_inode+0x132/0x520 mm/shmem.c:1417
 evict+0x2a5/0x510 fs/inode.c:822
 iput_final fs/inode.c:2015 [inline]
 iput+0x430/0x5a0 fs/inode.c:2064
 dentry_unlink_inode+0x24a/0x260 fs/dcache.c:479
 dentry_kill+0x184/0x500 fs/dcache.c:826
 finish_dput+0x16/0x1d0 fs/dcache.c:1001
 dput+0x48/0x50 fs/dcache.c:1042
 __fput+0x43e/0x630 fs/file_table.c:520
 ____fput+0x1c/0x30 fs/file_table.c:540
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x4a4/0x1510 kernel/exit.c:1009
 do_group_exit+0xfe/0x140 kernel/exit.c:1152
 get_signal+0xe07/0xf10 kernel/signal.c:3046
 arch_do_signal_or_restart+0x96/0x480 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:101 [inline]
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:244 [inline]
 irqentry_exit_to_user_mode include/linux/irq-entry-common.h:315 [inline]
 irqentry_exit+0x14d/0x610 kernel/entry/common.c:165
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595

read to 0xffffea0004d27ad8 of 8 bytes by task 31727 on cpu 0:
 folio_mapping+0xa1/0xe0 mm/util.c:732
 folio_evictable mm/internal.h:575 [inline]
 sort_folio mm/vmscan.c:4589 [inline]
 scan_folios mm/vmscan.c:4692 [inline]
 isolate_folios mm/vmscan.c:4780 [inline]
 evict_folios+0xdc7/0x2d60 mm/vmscan.c:4822
 try_to_shrink_lruvec+0x74d/0x8b0 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+0x67c/0x1e30 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
 mem_cgroup_resize_max+0x1cd/0x240 mm/memcontrol-v1.c:1522
 mem_cgroup_write+0x1ad/0x250 mm/memcontrol-v1.c:-1
 cgroup_file_write+0x197/0x350 kernel/cgroup/cgroup.c:4337
 kernfs_fop_write_iter+0x1d2/0x2e0 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x57f/0x9a0 fs/read_write.c:687
 ksys_write+0xdc/0x1a0 fs/read_write.c:739
 __do_sys_write fs/read_write.c:750 [inline]
 __se_sys_write fs/read_write.c:747 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:747
 x64_sys_call+0x154e/0x2550 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888120503848 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 31727 Comm: syz.7.8512 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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