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BUG: KCSAN: data-race in find_get_block_common / has_bh_in_lru

read-write to 0xffff888237c26f50 of 8 bytes by task 16637 on cpu 0:
 bh_lru_install fs/buffer.c:1345 [inline]
 find_get_block_common+0x4f0/0x960 fs/buffer.c:1410
 __getblk_slow fs/buffer.c:-1 [inline]
 bdev_getblk+0x30d/0x3b0 fs/buffer.c:1461
 getblk_unmovable include/linux/buffer_head.h:369 [inline]
 ext4_getblk+0x1b6/0x510 fs/ext4/inode.c:993
 ext4_bread_batch+0x5c/0x320 fs/ext4/inode.c:1062
 __ext4_find_entry+0x840/0xf40 fs/ext4/namei.c:1601
 ext4_lookup_entry fs/ext4/namei.c:1703 [inline]
 ext4_lookup+0xbb/0x390 fs/ext4/namei.c:1771
 lookup_open fs/namei.c:3686 [inline]
 open_last_lookups fs/namei.c:3807 [inline]
 path_openat+0xcf3/0x2170 fs/namei.c:4043
 do_filp_open+0x109/0x230 fs/namei.c:4073
 do_sys_openat2+0xa6/0x110 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_creat fs/open.c:1528 [inline]
 __se_sys_creat fs/open.c:1522 [inline]
 __x64_sys_creat+0x65/0x90 fs/open.c:1522
 x64_sys_call+0x2d94/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:86
 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 0xffff888237c26f50 of 8 bytes by task 11797 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1551
 cpu_needs_drain mm/swap.c:785 [inline]
 __lru_add_drain_all+0x234/0x3f0 mm/swap.c:872
 lru_add_drain_all+0x10/0x20 mm/swap.c:888
 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:1766
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7395
 deactivate_locked_super+0x75/0x1c0 fs/super.c:474
 deactivate_super+0x97/0xa0 fs/super.c:507
 cleanup_mnt+0x269/0x2e0 fs/namespace.c:1375
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1382
 task_work_run+0x131/0x1a0 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:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0xffff8881199f9820

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 11797 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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