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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 51 on cpu 0:
 bh_lru_install fs/buffer.c:1345 [inline]
 find_get_block_common+0x4f0/0x960 fs/buffer.c:1410
 __find_get_block_nonatomic fs/buffer.c:1429 [inline]
 bdev_getblk+0x83/0x3b0 fs/buffer.c:1453
 __getblk include/linux/buffer_head.h:380 [inline]
 sb_getblk include/linux/buffer_head.h:386 [inline]
 __ext4_get_inode_loc+0x303/0x930 fs/ext4/inode.c:4866
 __ext4_get_inode_loc_noinmem fs/ext4/inode.c:4979 [inline]
 ext4_write_inode+0x1ca/0x3c0 fs/ext4/inode.c:5754
 write_inode fs/fs-writeback.c:1525 [inline]
 __writeback_single_inode+0x319/0x7c0 fs/fs-writeback.c:1745
 writeback_sb_inodes+0x48f/0xa30 fs/fs-writeback.c:1976
 wb_writeback+0x252/0x5c0 fs/fs-writeback.c:2156
 wb_do_writeback fs/fs-writeback.c:2303 [inline]
 wb_workfn+0x194/0x910 fs/fs-writeback.c:2343
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3319
 worker_thread+0x582/0x770 kernel/workqueue.c:3400
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237c26f50 of 8 bytes by task 3303 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1551
 smp_call_function_many_cond+0x2a6/0xc60 kernel/smp.c:821
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1044
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1560
 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:699
 __fput+0x29b/0x650 fs/file_table.c:468
 ____fput+0x1c/0x30 fs/file_table.c:496
 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: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: 0xffff8881071f05b0 -> 0xffff88811a0ecd00

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3303 Comm: syz-executor Not tainted 6.17.0-rc1-syzkaller-00036-gdfc0f6373094 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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