syzbot

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BUG: KCSAN: data-race in delete_from_page_cache_batch / folio_mapping

write to 0xffffea0007007218 of 8 bytes by task 31821 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 0xffffea0007007218 of 8 bytes by task 3306 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
 lru_add_drain_cpu+0x66/0x210 mm/swap.c:648
 lru_add_drain mm/swap.c:737 [inline]
 __folio_batch_release+0x44/0xb0 mm/swap.c:1059
 folio_batch_release include/linux/pagevec.h:101 [inline]
 shmem_undo_range+0x3af/0xb10 mm/shmem.c:1137
 shmem_truncate_range mm/shmem.c:1249 [inline]
 shmem_evict_inode+0x12e/0x510 mm/shmem.c:1379
 evict+0x2af/0x510 fs/inode.c:837
 iput_final fs/inode.c:1954 [inline]
 iput+0x4b9/0x650 fs/inode.c:2006
 dentry_unlink_inode+0x24f/0x260 fs/dcache.c:467
 __dentry_kill+0x13f/0x460 fs/dcache.c:670
 finish_dput+0x2b/0x200 fs/dcache.c:879
 dput+0x52/0x60 fs/dcache.c:928
 end_renaming fs/namei.c:4061 [inline]
 do_renameat2+0x475/0x850 fs/namei.c:6058
 __do_sys_rename fs/namei.c:6099 [inline]
 __se_sys_rename fs/namei.c:6097 [inline]
 __x64_sys_rename+0x58/0x70 fs/namei.c:6097
 x64_sys_call+0x24e/0x3000 arch/x86/include/generated/asm/syscalls_64.h:83
 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

value changed: 0xffff888100483720 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3306 Comm: udevd Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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