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BUG: KCSAN: data-race in delete_from_page_cache_batch / folio_mapping

write to 0xffffea000412bf98 of 8 bytes by task 7396 on cpu 1:
 page_cache_delete_batch mm/filemap.c:310 [inline]
 delete_from_page_cache_batch+0x32c/0x740 mm/filemap.c:336
 truncate_inode_pages_range+0x1fe/0x7e0 mm/truncate.c:405
 truncate_inode_pages+0x24/0x30 mm/truncate.c:485
 kill_bdev block/bdev.c:91 [inline]
 set_blocksize+0x254/0x310 block/bdev.c:207
 sb_set_blocksize+0x93/0x170 block/bdev.c:241
 sb_min_blocksize+0x53/0x60 block/bdev.c:256
 ext4_load_super fs/ext4/super.c:5091 [inline]
 __ext4_fill_super fs/ext4/super.c:5312 [inline]
 ext4_fill_super+0x3a1/0x3800 fs/ext4/super.c:5777
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1691
 get_tree_bdev+0x1f/0x30 fs/super.c:1714
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5809
 vfs_get_tree+0x57/0x1d0 fs/super.c:1751
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3636 [inline]
 do_new_mount+0x288/0x700 fs/namespace.c:3712
 path_mount+0x4d0/0xbc0 fs/namespace.c:4022
 do_mount fs/namespace.c:4035 [inline]
 __do_sys_mount fs/namespace.c:4224 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4201
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4201
 x64_sys_call+0x2cca/0x3000 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffea000412bf98 of 8 bytes by task 7397 on cpu 0:
 folio_mapping+0xa1/0xe0 mm/util.c:703
 folio_evictable mm/internal.h:499 [inline]
 lru_add+0x8d/0x480 mm/swap.c:136
 folio_batch_move_lru+0x1c5/0x270 mm/swap.c:172
 __folio_batch_add_and_move mm/swap.c:196 [inline]
 folio_add_lru+0x149/0x1e0 mm/swap.c:511
 folio_add_lru_vma+0x49/0x70 mm/swap.c:530
 do_anonymous_page mm/memory.c:5272 [inline]
 do_pte_missing mm/memory.c:4402 [inline]
 handle_pte_fault mm/memory.c:6276 [inline]
 __handle_mm_fault mm/memory.c:6414 [inline]
 handle_mm_fault+0x2c45/0x3030 mm/memory.c:6583
 do_user_addr_fault+0x62f/0x1050 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618

value changed: 0xffff888100482aa0 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 7397 Comm: syz.3.889 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
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