====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:5/1112 is trying to acquire lock: ffff8880521ce990 (jbd2_handle){++++}-{0:0}, at: wait_transaction_locked+0x1a6/0x270 fs/jbd2/transaction.c:177 but task is already holding lock: ffff888025a878e8 (&journal->j_trans_barrier){.+.+}-{3:3}, at: ocfs2_start_trans+0x3a4/0x6f0 fs/ocfs2/journal.c:374 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&journal->j_trans_barrier){.+.+}-{3:3}: down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520 ocfs2_start_trans+0x3a4/0x6f0 fs/ocfs2/journal.c:374 ocfs2_shutdown_local_alloc+0x1f8/0xaa0 fs/ocfs2/localalloc.c:416 ocfs2_dismount_volume+0x1ff/0x940 fs/ocfs2/super.c:1882 generic_shutdown_super+0x130/0x340 fs/super.c:501 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191 task_work_run+0x1d0/0x260 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #4 (sb_internal#3){.+.+}-{0:0}: percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1891 [inline] sb_start_intwrite include/linux/fs.h:2013 [inline] ocfs2_start_trans+0x2a5/0x6f0 fs/ocfs2/journal.c:372 ocfs2_acquire_dquot+0x681/0xb20 fs/ocfs2/quota_global.c:848 dqget+0x778/0xeb0 fs/quota/dquot.c:988 dquot_set_dqblk+0x27/0xf90 fs/quota/dquot.c:2833 quota_setquota+0x4d6/0x590 fs/quota/quota.c:310 __do_sys_quotactl fs/quota/quota.c:960 [inline] __se_sys_quotactl+0x28b/0x6f0 fs/quota/quota.c:916 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #3 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}: down_write+0x36/0x60 kernel/locking/rwsem.c:1573 ocfs2_create_local_dquot+0x1a5/0x18e0 fs/ocfs2/quota_local.c:1224 ocfs2_acquire_dquot+0x7c6/0xb20 fs/ocfs2/quota_global.c:871 dqget+0x778/0xeb0 fs/quota/dquot.c:988 dquot_set_dqblk+0x27/0xf90 fs/quota/dquot.c:2833 quota_setquota+0x4d6/0x590 fs/quota/quota.c:310 __do_sys_quotactl fs/quota/quota.c:960 [inline] __se_sys_quotactl+0x28b/0x6f0 fs/quota/quota.c:916 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #2 (&dquot->dq_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12d/0xaf0 kernel/locking/mutex.c:747 dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6811 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412 __dquot_free_space+0x7ec/0xbc0 fs/quota/dquot.c:1942 dquot_free_space_nodirty include/linux/quotaops.h:379 [inline] dquot_free_space include/linux/quotaops.h:384 [inline] dquot_free_block include/linux/quotaops.h:395 [inline] ext4_mb_clear_bb fs/ext4/mballoc.c:6154 [inline] ext4_free_blocks+0x1bf3/0x26a0 fs/ext4/mballoc.c:6284 ext4_remove_blocks fs/ext4/extents.c:2526 [inline] ext4_ext_rm_leaf fs/ext4/extents.c:2692 [inline] ext4_ext_remove_space+0x225f/0x44c0 fs/ext4/extents.c:2940 ext4_ext_truncate+0x211/0x370 fs/ext4/extents.c:4470 ext4_truncate+0xa23/0x1240 fs/ext4/inode.c:4295 ext4_evict_inode+0xb41/0x1110 fs/ext4/inode.c:286 evict+0x4c9/0x8d0 fs/inode.c:705 ext4_orphan_cleanup+0xbeb/0x1420 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5556 [inline] ext4_fill_super+0x7829/0x7dc0 fs/ext4/super.c:5687 get_tree_bdev+0x3f1/0x610 fs/super.c:1366 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #1 (&ei->i_data_sem){++++}-{3:3}: down_write+0x36/0x60 kernel/locking/rwsem.c:1573 ext4_truncate+0x999/0x1240 fs/ext4/inode.c:4290 ext4_setattr+0x10cb/0x19f0 fs/ext4/inode.c:5649 notify_change+0xc74/0xf40 fs/attr.c:499 do_truncate+0x1ac/0x240 fs/open.c:65 do_sys_ftruncate+0x312/0x3c0 fs/open.c:193 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (jbd2_handle){++++}-{0:0}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 wait_transaction_locked+0x1bf/0x270 fs/jbd2/transaction.c:177 add_transaction_credits fs/jbd2/transaction.c:241 [inline] start_this_handle+0x7ec/0x2230 fs/jbd2/transaction.c:422 jbd2__journal_start+0x2b7/0x5a0 fs/jbd2/transaction.c:520 jbd2_journal_start+0x26/0x30 fs/jbd2/transaction.c:559 ocfs2_start_trans+0x3b0/0x6f0 fs/ocfs2/journal.c:376 ocfs2_release_dquot+0x47c/0xc70 fs/ocfs2/quota_global.c:749 quota_release_workfn+0x35e/0x610 fs/quota/dquot.c:848 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 other info that might help us debug this: Chain exists of: jbd2_handle --> sb_internal#3 --> &journal->j_trans_barrier Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&journal->j_trans_barrier); lock(sb_internal#3); lock(&journal->j_trans_barrier); lock(jbd2_handle); *** DEADLOCK *** 7 locks held by kworker/u4:5/1112: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc900055cfd00 ((quota_release_work).work){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #2: ffff888043cf0aa8 (&dquot->dq_lock){+.+.}-{3:3}, at: ocfs2_release_dquot+0x260/0xc70 fs/ocfs2/quota_global.c:729 #3: ffff88804f4009c8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #3: ffff88804f4009c8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}, at: ocfs2_lock_global_qf+0x1d7/0x290 fs/ocfs2/quota_global.c:313 #4: ffff88804f400660 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_lock_global_qf+0x1fe/0x290 fs/ocfs2/quota_global.c:314 #5: ffff88807c1d4650 (sb_internal#3){.+.+}-{0:0}, at: ocfs2_release_dquot+0x47c/0xc70 fs/ocfs2/quota_global.c:749 #6: ffff888025a878e8 (&journal->j_trans_barrier){.+.+}-{3:3}, at: ocfs2_start_trans+0x3a4/0x6f0 fs/ocfs2/journal.c:374 stack backtrace: CPU: 1 PID: 1112 Comm: kworker/u4:5 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_unbound quota_release_workfn Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 wait_transaction_locked+0x1bf/0x270 fs/jbd2/transaction.c:177 add_transaction_credits fs/jbd2/transaction.c:241 [inline] start_this_handle+0x7ec/0x2230 fs/jbd2/transaction.c:422 jbd2__journal_start+0x2b7/0x5a0 fs/jbd2/transaction.c:520 jbd2_journal_start+0x26/0x30 fs/jbd2/transaction.c:559 ocfs2_start_trans+0x3b0/0x6f0 fs/ocfs2/journal.c:376 ocfs2_release_dquot+0x47c/0xc70 fs/ocfs2/quota_global.c:749 quota_release_workfn+0x35e/0x610 fs/quota/dquot.c:848 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295