EXT4-fs (loop2): 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 0xffff888237d277e0 of 8 bytes by task 2947 on cpu 1:
 bh_lru_install fs/buffer.c:1230 [inline]
 find_get_block_common+0x45c/0x870 fs/buffer.c:1295
 __getblk_slow fs/buffer.c:-1 [inline]
 bdev_getblk+0x310/0x3c0 fs/buffer.c:1346
 __getblk include/linux/buffer_head.h:378 [inline]
 jbd2_journal_get_descriptor_buffer+0xce/0x210 fs/jbd2/journal.c:975
 journal_submit_commit_record+0x7e/0x400 fs/jbd2/commit.c:129
 jbd2_journal_commit_transaction+0x1fdf/0x3260 fs/jbd2/commit.c:901
 kjournald2+0x211/0x3d0 fs/jbd2/journal.c:200
 kthread+0x223/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237d277e0 of 8 bytes by task 3305 on cpu 0:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1436
 smp_call_function_many_cond+0x2d1/0xbc0 kernel/smp.c:936
 on_each_cpu_cond_mask+0x35/0x50 kernel/smp.c:1169
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1445
 invalidate_bdev+0x42/0x70 block/bdev.c:99
 ext4_put_super+0x620/0x7c0 fs/ext4/super.c:1357
 generic_shutdown_super+0xee/0x220 fs/super.c:755
 kill_block_super+0x2d/0xb0 fs/super.c:1904
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7527
 deactivate_locked_super+0x75/0x200 fs/super.c:589
 deactivate_super+0x9a/0xb0 fs/super.c:618
 cleanup_mnt+0x2c3/0x340 fs/namespace.c:1317
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1324
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1e4/0x8c0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
 do_syscall_64+0x212/0x360 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff88811b8de360 -> 0xffff88810071a240

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3305 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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