EXT4-fs (loop0): unmounting filesystem 00000000-0500-0000-0000-000000000000.
==================================================================
BUG: KCSAN: data-race in find_get_block_common / has_bh_in_lru

read-write to 0xffff888237c27550 of 8 bytes by task 23380 on cpu 0:
 bh_lru_install fs/buffer.c:1345 [inline]
 find_get_block_common+0x498/0x8e0 fs/buffer.c:1410
 bdev_getblk+0x4d/0x3f0 include/linux/gfp.h:-1
 getblk_unmovable include/linux/buffer_head.h:369 [inline]
 ext4_getblk+0x1ca/0x530 fs/ext4/inode.c:999
 ext4_bread+0x28/0x110 fs/ext4/inode.c:1047
 ext4_quota_write+0x166/0x360 fs/ext4/super.c:7350
 qtree_write_dquot+0x149/0x300 fs/quota/quota_tree.c:462
 v2_write_dquot+0xd9/0x130 fs/quota/quota_v2.c:372
 dquot_commit+0x21b/0x260 fs/quota/dquot.c:515
 ext4_write_dquot+0x126/0x1d0 fs/ext4/super.c:6962
 ext4_mark_dquot_dirty+0x95/0xd0 fs/ext4/super.c:7039
 mark_dquot_dirty fs/quota/dquot.c:373 [inline]
 mark_all_dquot_dirty fs/quota/dquot.c:413 [inline]
 __dquot_free_space+0x65a/0x800 fs/quota/dquot.c:1931
 dquot_free_space_nodirty include/linux/quotaops.h:374 [inline]
 dquot_free_space include/linux/quotaops.h:379 [inline]
 dquot_free_block include/linux/quotaops.h:390 [inline]
 ext4_mb_clear_bb fs/ext4/mballoc.c:6672 [inline]
 ext4_free_blocks+0xe9c/0x1480 fs/ext4/mballoc.c:6792
 ext4_remove_blocks fs/ext4/extents.c:2551 [inline]
 ext4_ext_rm_leaf fs/ext4/extents.c:2716 [inline]
 ext4_ext_remove_space+0x183f/0x2a30 fs/ext4/extents.c:2965
 ext4_ext_truncate+0xc7/0x160 fs/ext4/extents.c:4484
 ext4_truncate+0x70a/0xad0 fs/ext4/inode.c:4612
 ext4_truncate_failed_write fs/ext4/truncate.h:22 [inline]
 ext4_write_end+0x548/0x730 fs/ext4/inode.c:1491
 ext4_da_write_end+0x65/0x800 fs/ext4/inode.c:3278
 generic_perform_write+0x311/0x490 mm/filemap.c:4335
 ext4_buffered_write_iter+0x1ee/0x3c0 fs/ext4/file.c:299
 ext4_file_write_iter+0x380/0xf70 fs/ext4/file.c:-1
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5a6/0x9f0 fs/read_write.c:686
 ksys_pwrite64 fs/read_write.c:793 [inline]
 __do_sys_pwrite64 fs/read_write.c:801 [inline]
 __se_sys_pwrite64 fs/read_write.c:798 [inline]
 __x64_sys_pwrite64+0xfd/0x150 fs/read_write.c:798
 x64_sys_call+0x9f7/0x3000 arch/x86/include/generated/asm/syscalls_64.h:19
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c27550 of 8 bytes by task 20699 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1551
 cpu_needs_drain mm/swap.c:787 [inline]
 __lru_add_drain_all+0x287/0x450 mm/swap.c:877
 lru_add_drain_all+0x10/0x20 mm/swap.c:893
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 ext4_put_super+0x624/0x7d0 fs/ext4/super.c:1348
 generic_shutdown_super+0xe6/0x210 fs/super.c:643
 kill_block_super+0x2a/0x70 fs/super.c:1722
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7444
 deactivate_locked_super+0x75/0x1c0 fs/super.c:474
 deactivate_super+0x97/0xa0 fs/super.c:507
 cleanup_mnt+0x2bb/0x330 fs/namespace.c:1318
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1325
 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:44 [inline]
 exit_to_user_mode_loop+0x1f7/0x6f0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x1d3/0x2a0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0xffff88811a7e0340

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 20699 Comm: syz-executor Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
==================================================================
EXT4-fs (loop0): unmounting filesystem 00000000-0000-0000-0000-000000000000.