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BUG: KCSAN: data-race in delete_from_page_cache_batch / folio_mapping

write to 0xffffea0004bb1ad8 of 8 bytes by task 6725 on cpu 0:
 page_cache_delete_batch mm/filemap.c:310 [inline]
 delete_from_page_cache_batch+0x310/0x720 mm/filemap.c:336
 truncate_inode_pages_range+0x1f3/0x7d0 mm/truncate.c:405
 truncate_inode_pages+0x24/0x30 mm/truncate.c:485
 kill_bdev block/bdev.c:91 [inline]
 blkdev_flush_mapping+0x9e/0x1a0 block/bdev.c:715
 blkdev_put_whole block/bdev.c:722 [inline]
 bdev_release+0x2c1/0x3d0 block/bdev.c:1147
 blkdev_release+0x15/0x20 block/fops.c:680
 __fput+0x29e/0x630 fs/file_table.c:512
 fput_close_sync+0xad/0x190 fs/file_table.c:617
 __do_sys_close fs/open.c:1511 [inline]
 __se_sys_close fs/open.c:1496 [inline]
 __x64_sys_close+0x55/0xf0 fs/open.c:1496
 x64_sys_call+0x275d/0x3020 arch/x86/include/generated/asm/syscalls_64.h:4
 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 0xffffea0004bb1ad8 of 8 bytes by task 6876 on cpu 1:
 folio_mapping+0xa1/0xe0 mm/util.c:732
 folio_evictable mm/internal.h:575 [inline]
 lru_add+0x8d/0x460 mm/swap.c:136
 folio_batch_move_lru+0x2a3/0x3a0 mm/swap.c:200
 __folio_batch_add_and_move mm/swap.c:231 [inline]
 folio_add_lru+0x149/0x250 mm/swap.c:562
 folio_add_lru_vma+0x49/0x70 mm/swap.c:581
 map_anon_folio_pte_nopf+0x1ca/0x3d0 mm/memory.c:5266
 map_anon_folio_pte_pf+0x6b/0x160 mm/memory.c:5276
 do_anonymous_page mm/memory.c:5379 [inline]
 do_pte_missing mm/memory.c:4564 [inline]
 handle_pte_fault mm/memory.c:6379 [inline]
 __handle_mm_fault mm/memory.c:6517 [inline]
 handle_mm_fault+0x2cdc/0x2da0 mm/memory.c:6686
 do_user_addr_fault+0x402/0x1060 arch/x86/mm/fault.c:1394
 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
 rep_movs_alternative+0x4a/0xa0 arch/x86/lib/copy_user_64.S:68
 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline]
 copy_to_user_iter lib/iov_iter.c:25 [inline]
 iterate_ubuf include/linux/iov_iter.h:30 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:302 [inline]
 iterate_and_advance include/linux/iov_iter.h:330 [inline]
 _copy_to_iter+0x141/0xea0 lib/iov_iter.c:197
 copy_page_to_iter+0x174/0x210 lib/iov_iter.c:374
 copy_folio_to_iter include/linux/uio.h:204 [inline]
 filemap_read+0x3ed/0xa20 mm/filemap.c:2865
 blkdev_read_iter+0x21e/0x2d0 block/fops.c:830
 new_sync_read fs/read_write.c:493 [inline]
 vfs_read+0x699/0x7c0 fs/read_write.c:574
 ksys_read+0xdc/0x1a0 fs/read_write.c:716
 __do_sys_read fs/read_write.c:725 [inline]
 __se_sys_read fs/read_write.c:723 [inline]
 __x64_sys_read+0x40/0x50 fs/read_write.c:723
 x64_sys_call+0x2886/0x3020 arch/x86/include/generated/asm/syscalls_64.h:1
 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: 0xffff88810048c128 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 6876 Comm: udevd Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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