==================================================================
BUG: KCSAN: data-race in __filemap_remove_folio / folio_mapping

write to 0xffffea0005e85218 of 8 bytes by task 10776 on cpu 0:
 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:825
 iput_final fs/inode.c:2019 [inline]
 iput+0x430/0x5a0 fs/inode.c:2068
 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+0x4a4/0x1500 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 0xffffea0005e85218 of 8 bytes by task 10773 on cpu 1:
 folio_mapping+0xa1/0xe0 mm/util.c:732
 folio_evictable mm/internal.h:575 [inline]
 evict_folios+0x2300/0x2d60 mm/vmscan.c:4846
 try_to_shrink_lruvec+0x74d/0x8b0 mm/vmscan.c:4983
 shrink_one+0x147/0x400 mm/vmscan.c:5024
 shrink_many mm/vmscan.c:5087 [inline]
 lru_gen_shrink_node mm/vmscan.c:5165 [inline]
 shrink_node+0x193a/0x1e30 mm/vmscan.c:6154
 shrink_zones mm/vmscan.c:6410 [inline]
 do_try_to_free_pages+0x408/0xc90 mm/vmscan.c:6472
 try_to_free_pages+0x362/0x820 mm/vmscan.c:6711
 __perform_reclaim mm/page_alloc.c:4405 [inline]
 __alloc_pages_direct_reclaim+0x4e/0xd0 mm/page_alloc.c:4427
 __alloc_pages_slowpath+0x2d6/0x620 mm/page_alloc.c:4876
 __alloc_frozen_pages_noprof+0x270/0x350 mm/page_alloc.c:5317
 alloc_pages_mpol+0xa9/0x1d0 mm/mempolicy.c:2490
 folio_alloc_mpol_noprof+0x39/0x80 mm/mempolicy.c:2509
 __swap_cache_alloc mm/swap_state.c:434 [inline]
 swap_cache_alloc_folio+0x180/0x5e0 mm/swap_state.c:524
 swap_cache_read_folio mm/swap_state.c:646 [inline]
 swap_cluster_readahead+0x2b1/0x460 mm/swap_state.c:831
 swapin_readahead+0xd8/0x8a0 mm/swap_state.c:984
 do_swap_page+0x2a2/0x1ec0 mm/memory.c:4836
 handle_pte_fault mm/memory.c:6382 [inline]
 __handle_mm_fault mm/memory.c:6517 [inline]
 handle_mm_fault+0xb3c/0x2da0 mm/memory.c:6686
 do_user_addr_fault+0x634/0x1060 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595

value changed: 0xffff888103e7e540 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 10773 Comm: syz.8.2011 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
==================================================================