EXT4-fs (loop4): unmounting filesystem 00000000-0000-0000-0000-000000000000.
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BUG: KCSAN: data-race in find_get_block_common / has_bh_in_lru

read-write to 0xffff888237c26f60 of 8 bytes by task 5225 on cpu 0:
 bh_lru_install fs/buffer.c:1351 [inline]
 find_get_block_common+0x5f8/0x960 fs/buffer.c:1416
 __find_get_block_nonatomic fs/buffer.c:1435 [inline]
 bdev_getblk+0x83/0x3d0 fs/buffer.c:1459
 __bread_gfp+0x51/0x250 fs/buffer.c:1521
 sb_bread include/linux/buffer_head.h:348 [inline]
 fat__get_entry fs/fat/dir.c:100 [inline]
 fat_get_entry+0x46e/0x5d0 fs/fat/dir.c:128
 fat_get_short_entry fs/fat/dir.c:885 [inline]
 fat_scan+0x103/0x200 fs/fat/dir.c:970
 vfat_find_form fs/fat/namei_vfat.c:236 [inline]
 vfat_create_shortname fs/fat/namei_vfat.c:445 [inline]
 vfat_build_slots fs/fat/namei_vfat.c:608 [inline]
 vfat_add_entry+0x1200/0x1b90 fs/fat/namei_vfat.c:669
 vfat_create+0xa8/0x190 fs/fat/namei_vfat.c:768
 lookup_open fs/namei.c:3708 [inline]
 open_last_lookups fs/namei.c:3807 [inline]
 path_openat+0x1102/0x2170 fs/namei.c:4043
 do_filp_open+0x109/0x230 fs/namei.c:4073
 do_sys_openat2+0xa6/0x110 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_open fs/open.c:1460 [inline]
 __se_sys_open fs/open.c:1456 [inline]
 __x64_sys_open+0xe6/0x110 fs/open.c:1456
 x64_sys_call+0x14d4/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:3
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c26f60 of 8 bytes by task 3306 on cpu 1:
 has_bh_in_lru+0x150/0x1f0 fs/buffer.c:1557
 cpu_needs_drain mm/swap.c:780 [inline]
 __lru_add_drain_all+0x234/0x3f0 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+0x624/0x7d0 fs/ext4/super.c:1339
 generic_shutdown_super+0xe3/0x210 fs/super.c:643
 kill_block_super+0x2a/0x70 fs/super.c:1753
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7391
 deactivate_locked_super+0x75/0x1c0 fs/super.c:474
 deactivate_super+0x97/0xa0 fs/super.c:507
 cleanup_mnt+0x269/0x2e0 fs/namespace.c:1417
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1424
 task_work_run+0x12e/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0xffff88811b17d958

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3306 Comm: syz-executor Not tainted 6.16.0-rc1-syzkaller-00010-g2c4a1f3fe03e #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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