EXT4-fs (loop0): 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 4242 on cpu 1:
 bh_lru_install fs/buffer.c:1230 [inline]
 find_get_block_common+0x45c/0x870 fs/buffer.c:1295
 bdev_getblk+0x4c/0x3c0 include/linux/gfp.h:-1
 getblk_unmovable include/linux/buffer_head.h:367 [inline]
 ext4_getblk+0x1d8/0x540 fs/ext4/inode.c:1006
 ext4_bread+0x28/0x110 fs/ext4/inode.c:1054
 ext4_quota_read+0xe8/0x260 fs/ext4/super.c:7388
 read_blk fs/quota/quota_tree.c:61 [inline]
 find_tree_dqentry+0x11c/0x8f0 fs/quota/quota_tree.c:671
 find_dqentry fs/quota/quota_tree.c:716 [inline]
 qtree_read_dquot+0x338/0x480 fs/quota/quota_tree.c:736
 v2_read_dquot+0x92/0xd0 fs/quota/quota_v2.c:344
 dquot_acquire+0xc7/0x2b0 fs/quota/dquot.c:489
 ext4_acquire_dquot+0x15f/0x200 fs/ext4/super.c:7066
 dqget+0x51f/0x8b0 fs/quota/dquot.c:1002
 __dquot_initialize+0x28c/0x7c0 fs/quota/dquot.c:1462
 dquot_initialize+0x1a/0x30 fs/quota/dquot.c:1524
 ext4_mkdir+0xcb/0x790 fs/ext4/namei.c:3007
 vfs_mkdir+0x291/0x3e0 fs/namei.c:5410
 filename_mkdirat+0x138/0x300 fs/namei.c:5443
 __do_sys_mkdirat fs/namei.c:5464 [inline]
 __se_sys_mkdirat+0x32/0xf0 fs/namei.c:5461
 __x64_sys_mkdirat+0x43/0x50 fs/namei.c:5461
 x64_sys_call+0x368/0x2550 arch/x86/include/generated/asm/syscalls_64.h:259
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d277e0 of 8 bytes by task 3301 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
 kill_bdev block/bdev.c:89 [inline]
 blkdev_flush_mapping+0x94/0x1a0 block/bdev.c:757
 blkdev_put_whole block/bdev.c:764 [inline]
 bdev_release+0x2c1/0x3d0 block/bdev.c:1189
 blkdev_release+0x15/0x20 block/fops.c:687
 __fput+0x29e/0x630 fs/file_table.c:512
 ____fput+0x1c/0x30 fs/file_table.c:540
 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: 0xffff888105c827e0 -> 0xffff88810c9acc60

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3301 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
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