EXT4-fs (loop7): 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 0xffff888237d26f10 of 8 bytes by task 23599 on cpu 1:
 bh_lru_install fs/buffer.c:1351 [inline]
 find_get_block_common+0x4f0/0x960 fs/buffer.c:1416
 __find_get_block_nonatomic fs/buffer.c:1435 [inline]
 bdev_getblk+0x83/0x3d0 fs/buffer.c:1459
 __getblk include/linux/buffer_head.h:382 [inline]
 sb_getblk include/linux/buffer_head.h:388 [inline]
 __ext4_get_inode_loc+0x303/0x930 fs/ext4/inode.c:4797
 ext4_get_inode_loc fs/ext4/inode.c:4925 [inline]
 ext4_reserve_inode_write+0xd7/0x250 fs/ext4/inode.c:6244
 __ext4_mark_inode_dirty+0x8c/0x3f0 fs/ext4/inode.c:6422
 ext4_dirty_inode+0x92/0xc0 fs/ext4/inode.c:6459
 __mark_inode_dirty+0x15f/0x760 fs/fs-writeback.c:2527
 generic_update_time fs/inode.c:2064 [inline]
 inode_update_time fs/inode.c:2077 [inline]
 __file_update_time fs/inode.c:2305 [inline]
 file_update_time+0x288/0x2b0 fs/inode.c:2335
 ext4_page_mkwrite+0x18b/0xba0 fs/ext4/inode.c:6577
 do_page_mkwrite mm/memory.c:3378 [inline]
 do_shared_fault mm/memory.c:5686 [inline]
 do_fault mm/memory.c:5748 [inline]
 do_pte_missing mm/memory.c:4251 [inline]
 handle_pte_fault mm/memory.c:6089 [inline]
 __handle_mm_fault mm/memory.c:6232 [inline]
 handle_mm_fault+0x15ce/0x2be0 mm/memory.c:6401
 do_user_addr_fault+0x636/0x1090 arch/x86/mm/fault.c:1336
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

read to 0xffff888237d26f10 of 8 bytes by task 19993 on cpu 0:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1557
 smp_call_function_many_cond+0x389/0xbf0 kernel/smp.c:838
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1052
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1566
 kill_bdev block/bdev.c:90 [inline]
 blkdev_flush_mapping+0x9a/0x1a0 block/bdev.c:712
 blkdev_put_whole block/bdev.c:719 [inline]
 bdev_release+0x2bf/0x3d0 block/bdev.c:1144
 blkdev_release+0x15/0x20 block/fops.c:684
 __fput+0x29b/0x650 fs/file_table.c:465
 ____fput+0x1c/0x30 fs/file_table.c:493
 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 -> 0xffff888100479bc8

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 19993 Comm: syz-executor Not tainted 6.15.0-syzkaller-12426-ge271ed52b344 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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