====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:7/4462 is trying to acquire lock: ffff0000cdfea990 (jbd2_handle){++++}-{0:0}, at: wait_transaction_locked+0x15c/0x23c fs/jbd2/transaction.c:176 but task is already holding lock: ffff0000f59e80e8 (&journal->j_trans_barrier){.+.+}-{3:3}, at: ocfs2_start_trans+0x38c/0x6f4 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+0x64/0x300 kernel/locking/rwsem.c:1520 ocfs2_start_trans+0x38c/0x6f4 fs/ocfs2/journal.c:374 ocfs2_modify_bh+0xd8/0x44c fs/ocfs2/quota_local.c:101 ocfs2_local_read_info+0x1054/0x13c4 fs/ocfs2/quota_local.c:764 dquot_load_quota_sb+0x68c/0x998 fs/quota/dquot.c:2495 dquot_load_quota_inode+0x274/0x4dc fs/quota/dquot.c:2532 ocfs2_enable_quotas+0x17c/0x3c4 fs/ocfs2/super.c:926 ocfs2_fill_super+0x32f8/0x417c fs/ocfs2/super.c:1139 mount_bdev+0x264/0x35c fs/super.c:1443 ocfs2_mount+0x44/0x58 fs/ocfs2/super.c:1186 legacy_get_tree+0xd8/0x174 fs/fs_context.c:632 vfs_get_tree+0x90/0x278 fs/super.c:1573 do_new_mount+0x228/0x804 fs/namespace.c:3078 path_mount+0x5ac/0xe6c fs/namespace.c:3408 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount fs/namespace.c:3606 [inline] __arm64_sys_mount+0x4a0/0x5a0 fs/namespace.c:3606 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #4 (sb_internal#4){.+.+}-{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+0x20c/0x6f4 fs/ocfs2/journal.c:372 ocfs2_acquire_dquot+0x5d0/0xab0 fs/ocfs2/quota_global.c:848 dqget+0x638/0xa98 fs/quota/dquot.c:1013 __dquot_initialize+0x2e4/0xb30 fs/quota/dquot.c:1542 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1604 ocfs2_get_init_inode+0x140/0x1b4 fs/ocfs2/namei.c:202 ocfs2_mknod+0x7d4/0x218c fs/ocfs2/namei.c:310 ocfs2_mkdir+0x19c/0x51c fs/ocfs2/namei.c:657 vfs_mkdir+0x314/0x4d8 fs/namei.c:4114 do_mkdirat+0x1b8/0x3ec fs/namei.c:4139 __do_sys_mkdirat fs/namei.c:4154 [inline] __se_sys_mkdirat fs/namei.c:4152 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4152 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #3 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}: down_write+0x5c/0x88 kernel/locking/rwsem.c:1573 ocfs2_create_local_dquot+0x140/0x1444 fs/ocfs2/quota_local.c:1224 ocfs2_acquire_dquot+0x6dc/0xab0 fs/ocfs2/quota_global.c:871 dqget+0x638/0xa98 fs/quota/dquot.c:1013 __dquot_initialize+0x2e4/0xb30 fs/quota/dquot.c:1542 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1604 ocfs2_get_init_inode+0x140/0x1b4 fs/ocfs2/namei.c:202 ocfs2_mknod+0x7d4/0x218c fs/ocfs2/namei.c:310 ocfs2_mkdir+0x19c/0x51c fs/ocfs2/namei.c:657 vfs_mkdir+0x314/0x4d8 fs/namei.c:4114 do_mkdirat+0x1b8/0x3ec fs/namei.c:4139 __do_sys_mkdirat fs/namei.c:4154 [inline] __se_sys_mkdirat fs/namei.c:4152 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4152 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #2 (&dquot->dq_lock){+.+.}-{3:3}: __mutex_lock_common+0x1a0/0x1f3c kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 dquot_commit+0x54/0x1c8 fs/quota/dquot.c:535 ext4_write_dquot+0x1b4/0x320 fs/ext4/super.c:6817 ext4_mark_dquot_dirty+0xe8/0x150 fs/ext4/super.c:6894 mark_dquot_dirty fs/quota/dquot.c:400 [inline] mark_all_dquot_dirty+0x1f8/0x424 fs/quota/dquot.c:440 __dquot_free_space+0x768/0xaa4 fs/quota/dquot.c:1967 dquot_free_space_nodirty include/linux/quotaops.h:372 [inline] dquot_free_space include/linux/quotaops.h:377 [inline] dquot_free_block include/linux/quotaops.h:388 [inline] ext4_mb_clear_bb fs/ext4/mballoc.c:6153 [inline] ext4_free_blocks+0x18dc/0x2468 fs/ext4/mballoc.c:6283 ext4_remove_blocks fs/ext4/extents.c:2541 [inline] ext4_ext_rm_leaf fs/ext4/extents.c:2707 [inline] ext4_ext_remove_space+0x1618/0x3b98 fs/ext4/extents.c:2955 ext4_ext_truncate+0x170/0x218 fs/ext4/extents.c:4491 ext4_truncate+0xa00/0x1090 fs/ext4/inode.c:4302 ext4_evict_inode+0xbd0/0x1264 fs/ext4/inode.c:288 evict+0x3d8/0x824 fs/inode.c:705 iput_final fs/inode.c:1834 [inline] iput+0x728/0x7e8 fs/inode.c:1860 ext4_process_orphan+0x24c/0x2c0 fs/ext4/orphan.c:358 ext4_orphan_cleanup+0x964/0x1090 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5574 [inline] ext4_fill_super+0x5af8/0x63bc fs/ext4/super.c:5693 get_tree_bdev+0x35c/0x54c fs/super.c:1366 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5723 vfs_get_tree+0x90/0x278 fs/super.c:1573 do_new_mount+0x228/0x804 fs/namespace.c:3078 path_mount+0x5ac/0xe6c fs/namespace.c:3408 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount fs/namespace.c:3606 [inline] __arm64_sys_mount+0x4a0/0x5a0 fs/namespace.c:3606 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #1 (&ei->i_data_sem){++++}-{3:3}: down_write+0x5c/0x88 kernel/locking/rwsem.c:1573 ext4_map_blocks+0x720/0x160c fs/ext4/inode.c:674 mpage_map_one_extent fs/ext4/inode.c:2436 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2489 [inline] ext4_writepages+0xdbc/0x28fc fs/ext4/inode.c:2857 do_writepages+0x2c4/0x50c mm/page-writeback.c:2491 __writeback_single_inode+0x164/0x157c fs/fs-writeback.c:1673 writeback_sb_inodes+0x870/0x1470 fs/fs-writeback.c:1964 __writeback_inodes_wb+0x104/0x370 fs/fs-writeback.c:2035 wb_writeback+0x420/0xfdc fs/fs-writeback.c:2140 wb_check_background_flush fs/fs-writeback.c:2206 [inline] wb_do_writeback fs/fs-writeback.c:2294 [inline] wb_workfn+0xb40/0xe18 fs/fs-writeback.c:2321 process_one_work+0x7e4/0x13bc kernel/workqueue.c:2292 worker_thread+0x8cc/0xfe8 kernel/workqueue.c:2439 kthread+0x254/0x2e0 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850 -> #0 (jbd2_handle){++++}-{0:0}: check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3830 [inline] __lock_acquire+0x2808/0x6634 kernel/locking/lockdep.c:5063 lock_acquire+0x20c/0x638 kernel/locking/lockdep.c:5676 wait_transaction_locked+0x184/0x23c fs/jbd2/transaction.c:177 add_transaction_credits+0x104/0xaf0 fs/jbd2/transaction.c:-1 start_this_handle+0x4dc/0x125c fs/jbd2/transaction.c:422 jbd2__journal_start+0x288/0x530 fs/jbd2/transaction.c:520 jbd2_journal_start+0x3c/0x4c fs/jbd2/transaction.c:559 ocfs2_start_trans+0x398/0x6f4 fs/ocfs2/journal.c:376 ocfs2_release_dquot+0x3d0/0xac0 fs/ocfs2/quota_global.c:749 quota_release_workfn+0x374/0x618 fs/quota/dquot.c:875 process_one_work+0x7e4/0x13bc kernel/workqueue.c:2292 worker_thread+0x8cc/0xfe8 kernel/workqueue.c:2439 kthread+0x254/0x2e0 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850 other info that might help us debug this: Chain exists of: jbd2_handle --> sb_internal#4 --> &journal->j_trans_barrier Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&journal->j_trans_barrier); lock(sb_internal#4); lock(&journal->j_trans_barrier); lock(jbd2_handle); *** DEADLOCK *** 7 locks held by kworker/u4:7/4462: #0: ffff0000c4b03938 ((wq_completion)quota_events_unbound){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1 #1: ffff800021687c40 ((quota_release_work).work){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267 #2: ffff0000f63b42a8 (&dquot->dq_lock){+.+.}-{3:3}, at: ocfs2_release_dquot+0x238/0xac0 fs/ocfs2/quota_global.c:729 #3: ffff0000fb452648 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #3: ffff0000fb452648 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: ocfs2_lock_global_qf+0x190/0x23c fs/ocfs2/quota_global.c:313 #4: ffff0000fb4522e0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_lock_global_qf+0x1ac/0x23c fs/ocfs2/quota_global.c:314 #5: ffff0000dc268650 (sb_internal#4){.+.+}-{0:0}, at: ocfs2_release_dquot+0x3d0/0xac0 fs/ocfs2/quota_global.c:749 #6: ffff0000f59e80e8 (&journal->j_trans_barrier){.+.+}-{3:3}, at: ocfs2_start_trans+0x38c/0x6f4 fs/ocfs2/journal.c:374 stack backtrace: CPU: 1 PID: 4462 Comm: kworker/u4:7 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026 Workqueue: quota_events_unbound quota_release_workfn Call trace: dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 print_circular_bug+0x148/0x1b0 kernel/locking/lockdep.c:2048 check_noncircular+0x264/0x2f8 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3830 [inline] __lock_acquire+0x2808/0x6634 kernel/locking/lockdep.c:5063 lock_acquire+0x20c/0x638 kernel/locking/lockdep.c:5676 wait_transaction_locked+0x184/0x23c fs/jbd2/transaction.c:177 add_transaction_credits+0x104/0xaf0 fs/jbd2/transaction.c:-1 start_this_handle+0x4dc/0x125c fs/jbd2/transaction.c:422 jbd2__journal_start+0x288/0x530 fs/jbd2/transaction.c:520 jbd2_journal_start+0x3c/0x4c fs/jbd2/transaction.c:559 ocfs2_start_trans+0x398/0x6f4 fs/ocfs2/journal.c:376 ocfs2_release_dquot+0x3d0/0xac0 fs/ocfs2/quota_global.c:749 quota_release_workfn+0x374/0x618 fs/quota/dquot.c:875 process_one_work+0x7e4/0x13bc kernel/workqueue.c:2292 worker_thread+0x8cc/0xfe8 kernel/workqueue.c:2439 kthread+0x254/0x2e0 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850