EXT4-fs (loop8): unmounting filesystem 00000000-0000-0000-0000-000000000000.
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BUG: KCSAN: data-race in __find_get_block / has_bh_in_lru

read-write to 0xffff888237c26b30 of 8 bytes by task 18370 on cpu 0:
 bh_lru_install fs/buffer.c:1337 [inline]
 __find_get_block+0x430/0x8a0 fs/buffer.c:1400
 bdev_getblk+0x30/0x3b0 fs/buffer.c:1425
 __bread_gfp+0x52/0x280 fs/buffer.c:1485
 sb_bread include/linux/buffer_head.h:345 [inline]
 fat__get_entry fs/fat/dir.c:100 [inline]
 fat_get_entry+0x486/0x5f0 fs/fat/dir.c:128
 __fat_readdir+0x2a2/0xd80 fs/fat/dir.c:602
 fat_readdir+0x2f/0x40 fs/fat/dir.c:716
 iterate_dir+0x11d/0x310 fs/readdir.c:108
 __do_sys_getdents64 fs/readdir.c:403 [inline]
 __se_sys_getdents64+0x8c/0x1b0 fs/readdir.c:389
 __x64_sys_getdents64+0x43/0x50 fs/readdir.c:389
 x64_sys_call+0x1110/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:218
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c26b30 of 8 bytes by task 14603 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1521
 smp_call_function_many_cond+0x30a/0xbc0 kernel/smp.c:838
 on_each_cpu_cond_mask+0x3c/0x90 kernel/smp.c:1052
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1530
 kill_bdev block/bdev.c:90 [inline]
 blkdev_flush_mapping+0x9b/0x1a0 block/bdev.c:674
 blkdev_put_whole block/bdev.c:681 [inline]
 bdev_release+0x2f9/0x420 block/bdev.c:1106
 blkdev_release+0x15/0x20 block/fops.c:660
 __fput+0x2ac/0x640 fs/file_table.c:465
 ____fput+0x1c/0x30 fs/file_table.c:493
 task_work_run+0x13c/0x1b0 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/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0xffff888117d524e0

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 14603 Comm: syz-executor Not tainted 6.15.0-rc1-syzkaller-00333-g5aaaedb0cb54 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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