EXT4-fs (loop2): unmounting filesystem 00000000-0000-0000-0000-000000d40000.
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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 22256 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
 __getblk include/linux/buffer_head.h:379 [inline]
 sb_getblk include/linux/buffer_head.h:385 [inline]
 ext4_get_branch+0x1e0/0x3a0 fs/ext4/indirect.c:166
 ext4_find_shared+0xb1/0x270 fs/ext4/indirect.c:808
 ext4_ind_truncate+0x43f/0x880 fs/ext4/indirect.c:1159
 ext4_truncate+0x76d/0xb30 fs/ext4/inode.c:4233
 ext4_truncate_failed_write fs/ext4/truncate.h:22 [inline]
 ext4_write_end+0x530/0x770 fs/ext4/inode.c:1346
 generic_perform_write+0x31e/0x4b0 mm/filemap.c:4123
 ext4_buffered_write_iter+0x1ed/0x3c0 fs/ext4/file.c:299
 ext4_file_write_iter+0x3b2/0xf80 include/linux/fs.h:-1
 new_sync_write fs/read_write.c:591 [inline]
 vfs_write+0x79b/0x950 fs/read_write.c:684
 ksys_write+0xeb/0x1b0 fs/read_write.c:736
 __do_sys_write fs/read_write.c:747 [inline]
 __se_sys_write fs/read_write.c:744 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:744
 x64_sys_call+0x2a45/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:2
 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 21226 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1521
 cpu_needs_drain mm/swap.c:780 [inline]
 __lru_add_drain_all+0x23f/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+0x65b/0x910 fs/ext4/super.c:1343
 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:7393
 deactivate_locked_super+0x7d/0x1c0 fs/super.c:473
 deactivate_super+0x9f/0xb0 fs/super.c:506
 cleanup_mnt+0x26e/0x2e0 fs/namespace.c:1435
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1442
 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 -> 0xffff88810f052680

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 21226 Comm: syz-executor Not tainted 6.15.0-rc1-syzkaller-00246-g900241a5cc15 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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