==================================================================
BUG: KCSAN: data-race in __lru_add_drain_all / folios_put_refs

write to 0xffff888237d2a928 of 1 bytes by task 9584 on cpu 1:
 folio_batch_reinit include/linux/pagevec.h:50 [inline]
 folios_put_refs+0x26d/0x2b0 mm/swap.c:988
 folios_put include/linux/mm.h:1548 [inline]
 folio_batch_move_lru+0x202/0x230 mm/swap.c:175
 __folio_batch_add_and_move mm/swap.c:196 [inline]
 folio_add_lru+0x145/0x1f0 mm/swap.c:505
 filemap_add_folio+0x12c/0x1b0 mm/filemap.c:997
 __filemap_get_folio+0x32f/0x630 mm/filemap.c:1980
 grow_dev_folio fs/buffer.c:1039 [inline]
 grow_buffers fs/buffer.c:1105 [inline]
 __getblk_slow fs/buffer.c:1131 [inline]
 bdev_getblk+0x173/0x3b0 fs/buffer.c:1431
 __bread_gfp+0x52/0x280 fs/buffer.c:1485
 sb_bread include/linux/buffer_head.h:346 [inline]
 fat__get_entry fs/fat/dir.c:100 [inline]
 fat_get_entry+0x482/0x5f0 fs/fat/dir.c:128
 fat_get_short_entry fs/fat/dir.c:885 [inline]
 fat_subdirs+0xfa/0x190 fs/fat/dir.c:951
 fat_read_root+0x31d/0x360 fs/fat/inode.c:1345
 fat_fill_super+0x1521/0x1c30 fs/fat/inode.c:1814
 vfat_fill_super+0x24/0x30 fs/fat/namei_vfat.c:1197
 get_tree_bdev_flags+0x29f/0x310 fs/super.c:1636
 get_tree_bdev+0x1f/0x30 fs/super.c:1659
 vfat_get_tree+0x1c/0x30 fs/fat/namei_vfat.c:1202
 vfs_get_tree+0x56/0x1e0 fs/super.c:1814
 do_new_mount+0x227/0x690 fs/namespace.c:3560
 path_mount+0x49b/0xb30 fs/namespace.c:3887
 do_mount fs/namespace.c:3900 [inline]
 __do_sys_mount fs/namespace.c:4111 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:4088
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4088
 x64_sys_call+0x2c84/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d2a928 of 1 bytes by task 3306 on cpu 0:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:773 [inline]
 __lru_add_drain_all+0x136/0x3f0 mm/swap.c:867
 lru_add_drain_all+0x10/0x20 mm/swap.c:883
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 ext4_put_super+0x571/0x810 fs/ext4/super.c:1356
 generic_shutdown_super+0xe5/0x220 fs/super.c:642
 kill_block_super+0x2a/0x70 fs/super.c:1710
 ext4_kill_sb+0x44/0x80 fs/ext4/super.c:7368
 deactivate_locked_super+0x7d/0x1c0 fs/super.c:473
 deactivate_super+0x9f/0xb0 fs/super.c:506
 cleanup_mnt+0x268/0x2e0 fs/namespace.c:1413
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1420
 task_work_run+0x13a/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xa8/0x120 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3306 Comm: syz-executor Tainted: G        W          6.14.0-rc5-syzkaller-00013-g99fa936e8e4f #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================