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BUG: KCSAN: data-race in __filemap_remove_folio / folio_mapping

write to 0xffffea0006f92058 of 8 bytes by task 9803 on cpu 1:
 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:1153
 shmem_truncate_range mm/shmem.c:1269 [inline]
 shmem_evict_inode+0x134/0x520 mm/shmem.c:1397
 evict+0x2e0/0x550 fs/inode.c:810
 iput_final fs/inode.c:1897 [inline]
 iput+0x447/0x5b0 fs/inode.c:1923
 dentry_unlink_inode+0x24f/0x260 fs/dcache.c:466
 __dentry_kill+0x18d/0x4b0 fs/dcache.c:669
 dput+0x5e/0xd0 fs/dcache.c:911
 __fput+0x444/0x650 fs/file_table.c:476
 ____fput+0x1c/0x30 fs/file_table.c:496
 task_work_run+0x131/0x1a0 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x483/0x15c0 kernel/exit.c:961
 do_group_exit+0xff/0x140 kernel/exit.c:1102
 get_signal+0xe59/0xf70 kernel/signal.c:3034
 arch_do_signal_or_restart+0x96/0x480 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:40 [inline]
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 irqentry_exit_to_user_mode+0x5e/0xa0 kernel/entry/common.c:73
 irqentry_exit+0x12/0x50 kernel/entry/common.c:177
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

read to 0xffffea0006f92058 of 8 bytes by task 9978 on cpu 0:
 folio_mapping+0xa1/0x120 mm/util.c:702
 folio_evictable mm/internal.h:499 [inline]
 evict_folios+0x2ad0/0x3520 mm/vmscan.c:4754
 try_to_shrink_lruvec+0x5b5/0x950 mm/vmscan.c:4907
 lru_gen_shrink_lruvec mm/vmscan.c:5056 [inline]
 shrink_lruvec+0x22e/0x1b50 mm/vmscan.c:5815
 shrink_node_memcgs mm/vmscan.c:6051 [inline]
 shrink_node+0x686/0x2120 mm/vmscan.c:6092
 shrink_zones mm/vmscan.c:6336 [inline]
 do_try_to_free_pages+0x3f6/0xcd0 mm/vmscan.c:6398
 try_to_free_mem_cgroup_pages+0x1ab/0x410 mm/vmscan.c:6726
 try_charge_memcg+0x358/0x9e0 mm/memcontrol.c:2357
 try_charge mm/memcontrol.c:2499 [inline]
 charge_memcg+0x51/0xc0 mm/memcontrol.c:4702
 __mem_cgroup_charge+0x28/0xb0 mm/memcontrol.c:4719
 mem_cgroup_charge include/linux/memcontrol.h:654 [inline]
 shmem_alloc_and_add_folio mm/shmem.c:1957 [inline]
 shmem_get_folio_gfp+0x470/0xd60 mm/shmem.c:2597
 shmem_get_folio mm/shmem.c:2703 [inline]
 shmem_write_begin+0xa8/0x190 mm/shmem.c:3353
 generic_perform_write+0x184/0x490 mm/filemap.c:4175
 shmem_file_write_iter+0xc5/0xf0 mm/shmem.c:3528
 __kernel_write_iter+0x2d6/0x540 fs/read_write.c:619
 dump_emit_page fs/coredump.c:1296 [inline]
 dump_user_range+0x61e/0x8f0 fs/coredump.c:1370
 elf_core_dump+0x1e00/0x1f90 fs/binfmt_elf.c:2085
 coredump_write+0xb0d/0xe30 fs/coredump.c:1049
 vfs_coredump+0x142f/0x20c0 fs/coredump.c:1168
 get_signal+0xd85/0xf70 kernel/signal.c:3019
 arch_do_signal_or_restart+0x96/0x480 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:40 [inline]
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 irqentry_exit_to_user_mode+0x5e/0xa0 kernel/entry/common.c:73
 irqentry_exit+0x12/0x50 kernel/entry/common.c:177
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

value changed: 0xffff88812f6dcaa8 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 9978 Comm: syz.2.2168 Not tainted 6.16.0-syzkaller-12245-g2988dfed8a5d #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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