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BUG: KCSAN: data-race in __find_get_block / has_bh_in_lru

read-write to 0xffff888237d26b38 of 8 bytes by task 5369 on cpu 1:
 bh_lru_install fs/buffer.c:1337 [inline]
 __find_get_block+0x44d/0x8a0 fs/buffer.c:1400
 bdev_getblk+0x30/0x3b0 fs/buffer.c:1425
 getblk_unmovable include/linux/buffer_head.h:368 [inline]
 ext4_getblk+0x1bf/0x550 fs/ext4/inode.c:867
 ext4_bread+0x2c/0x110 fs/ext4/inode.c:915
 ext4_quota_read+0x108/0x1d0 fs/ext4/super.c:7253
 read_blk fs/quota/quota_tree.c:61 [inline]
 remove_tree+0x131/0x11d0 fs/quota/quota_tree.c:555
 qtree_delete_dquot fs/quota/quota_tree.c:617 [inline]
 qtree_release_dquot+0x17c/0x190 fs/quota/quota_tree.c:787
 v2_release_dquot+0x99/0xd0 fs/quota/quota_v2.c:391
 dquot_release+0x11d/0x240 fs/quota/dquot.c:537
 ext4_release_dquot+0x1ed/0x480 fs/ext4/super.c:-1
 quota_release_workfn+0x254/0x540 fs/quota/dquot.c:840
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4de/0xa20 kernel/workqueue.c:3319
 worker_thread+0x52c/0x710 kernel/workqueue.c:3400
 kthread+0x4b7/0x540 kernel/kthread.c:464
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237d26b38 of 8 bytes by task 10900 on cpu 0:
 has_bh_in_lru+0x54/0x1f0 fs/buffer.c:1521
 smp_call_function_many_cond+0x30a/0xbc0 kernel/smp.c:838
 on_each_cpu_cond_mask+0x3c/0x90 kernel/smp.c:1052
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1530
 kill_bdev block/bdev.c:90 [inline]
 blkdev_flush_mapping+0x9b/0x1a0 block/bdev.c:674
 blkdev_put_whole block/bdev.c:681 [inline]
 bdev_release+0x2f9/0x420 block/bdev.c:1106
 blkdev_release+0x15/0x20 block/fops.c:660
 __fput+0x2ac/0x640 fs/file_table.c:465
 ____fput+0x1c/0x30 fs/file_table.c:493
 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 -> 0xffff88811d0d21a0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 10900 Comm: syz-executor Not tainted 6.15.0-rc1-syzkaller-00095-g2eb959eeecc6 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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