EXT4-fs (loop8): mounted filesystem without journal. Quota mode: writeback. ====================================================== WARNING: possible circular locking dependency detected 6.1.142-syzkaller #0 Not tainted ------------------------------------------------------ syz.8.2306/12490 is trying to acquire lock: ffff0000cf87a0a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x50/0x1c4 fs/quota/dquot.c:507 but task is already holding lock: ffff0000dfd5f0e0 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x7c4/0x1770 fs/ext4/inode.c:672 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&ei->i_data_sem){++++}-{3:3}: down_write+0x5c/0x88 kernel/locking/rwsem.c:1573 ext4_map_blocks+0x7c4/0x1770 fs/ext4/inode.c:672 mpage_map_one_extent fs/ext4/inode.c:2434 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2487 [inline] ext4_writepages+0xd8c/0x284c fs/ext4/inode.c:2855 do_writepages+0x2c0/0x4fc mm/page-writeback.c:2491 __writeback_single_inode+0x164/0x157c fs/fs-writeback.c:1612 writeback_sb_inodes+0x824/0x1404 fs/fs-writeback.c:1903 __writeback_inodes_wb+0x110/0x394 fs/fs-writeback.c:1974 wb_writeback+0x414/0xfb0 fs/fs-writeback.c:2079 wb_check_background_flush fs/fs-writeback.c:2145 [inline] wb_do_writeback fs/fs-writeback.c:2233 [inline] wb_workfn+0xac0/0xd98 fs/fs-writeback.c:2260 process_one_work+0x7f4/0x13a8 kernel/workqueue.c:2292 worker_thread+0x8c8/0xfbc kernel/workqueue.c:2439 kthread+0x250/0x2d8 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:849 -> #4 (jbd2_handle){++++}-{0:0}: start_this_handle+0xfe0/0x122c fs/jbd2/transaction.c:463 jbd2__journal_start+0x288/0x51c fs/jbd2/transaction.c:520 jbd2_journal_start+0x3c/0x4c fs/jbd2/transaction.c:559 ocfs2_start_trans+0x380/0x6c4 fs/ocfs2/journal.c:376 ocfs2_shutdown_local_alloc+0x1ac/0x7e4 fs/ocfs2/localalloc.c:416 ocfs2_dismount_volume+0x1f0/0x93c fs/ocfs2/super.c:1882 ocfs2_put_super+0x108/0x390 fs/ocfs2/super.c:1609 generic_shutdown_super+0x130/0x324 fs/super.c:501 kill_block_super+0x70/0xdc fs/super.c:1470 deactivate_locked_super+0xac/0x124 fs/super.c:332 deactivate_super+0xe8/0x108 fs/super.c:363 cleanup_mnt+0x37c/0x404 fs/namespace.c:1182 __cleanup_mnt+0x20/0x30 fs/namespace.c:1189 task_work_run+0x1ec/0x270 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x1f70/0x2b0c arch/arm64/kernel/signal.c:1137 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x98/0x138 arch/arm64/kernel/entry-common.c:638 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 (&journal->j_trans_barrier){.+.+}-{3:3}: down_read+0x64/0x304 kernel/locking/rwsem.c:1520 ocfs2_start_trans+0x374/0x6c4 fs/ocfs2/journal.c:374 ocfs2_shutdown_local_alloc+0x1ac/0x7e4 fs/ocfs2/localalloc.c:416 ocfs2_dismount_volume+0x1f0/0x93c fs/ocfs2/super.c:1882 ocfs2_put_super+0x108/0x390 fs/ocfs2/super.c:1609 generic_shutdown_super+0x130/0x324 fs/super.c:501 kill_block_super+0x70/0xdc fs/super.c:1470 deactivate_locked_super+0xac/0x124 fs/super.c:332 deactivate_super+0xe8/0x108 fs/super.c:363 cleanup_mnt+0x37c/0x404 fs/namespace.c:1182 __cleanup_mnt+0x20/0x30 fs/namespace.c:1189 task_work_run+0x1ec/0x270 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x1f70/0x2b0c arch/arm64/kernel/signal.c:1137 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x98/0x138 arch/arm64/kernel/entry-common.c:638 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 (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/0x6c4 fs/ocfs2/journal.c:372 ocfs2_acquire_dquot+0x5bc/0xac4 fs/ocfs2/quota_global.c:848 dqget+0x654/0xccc fs/quota/dquot.c:988 dquot_set_dqblk+0x40/0xe50 fs/quota/dquot.c:2833 quota_setquota+0x400/0x490 fs/quota/quota.c:310 do_quotactl+0x65c/0x738 fs/quota/quota.c:802 __do_sys_quotactl fs/quota/quota.c:960 [inline] __se_sys_quotactl fs/quota/quota.c:916 [inline] __arm64_sys_quotactl+0x2ac/0x730 fs/quota/quota.c:916 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 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 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}: down_write+0x5c/0x88 kernel/locking/rwsem.c:1573 ocfs2_create_local_dquot+0x15c/0x1330 fs/ocfs2/quota_local.c:1224 ocfs2_acquire_dquot+0x6e8/0xac4 fs/ocfs2/quota_global.c:871 dqget+0x654/0xccc fs/quota/dquot.c:988 dquot_set_dqblk+0x40/0xe50 fs/quota/dquot.c:2833 quota_setquota+0x400/0x490 fs/quota/quota.c:310 do_quotactl+0x65c/0x738 fs/quota/quota.c:802 __do_sys_quotactl fs/quota/quota.c:960 [inline] __se_sys_quotactl fs/quota/quota.c:916 [inline] __arm64_sys_quotactl+0x2ac/0x730 fs/quota/quota.c:916 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 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 -> #0 (&dquot->dq_lock){+.+.}-{3:3}: 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+0x293c/0x6544 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x1f38 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+0x50/0x1c4 fs/quota/dquot.c:507 ext4_write_dquot+0x1b4/0x31c fs/ext4/super.c:6790 ext4_mark_dquot_dirty+0xe8/0x140 fs/ext4/super.c:6867 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0x1f8/0x424 fs/quota/dquot.c:412 __dquot_alloc_space+0x560/0xce8 fs/quota/dquot.c:1752 dquot_alloc_space_nodirty include/linux/quotaops.h:300 [inline] dquot_alloc_space include/linux/quotaops.h:313 [inline] dquot_alloc_block include/linux/quotaops.h:337 [inline] ext4_mb_new_blocks+0xd30/0x435c fs/ext4/mballoc.c:5727 ext4_ext_map_blocks+0x1018/0x559c fs/ext4/extents.c:4340 ext4_map_blocks+0x860/0x1770 fs/ext4/inode.c:679 ext4_alloc_file_blocks+0x2ac/0x8e0 fs/ext4/extents.c:4524 ext4_fallocate+0x784/0x1b60 fs/ext4/extents.c:4811 vfs_fallocate+0x4a4/0x5f4 fs/open.c:323 ksys_fallocate fs/open.c:346 [inline] __do_sys_fallocate fs/open.c:354 [inline] __se_sys_fallocate fs/open.c:352 [inline] __arm64_sys_fallocate+0xc0/0x110 fs/open.c:352 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 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 other info that might help us debug this: Chain exists of: &dquot->dq_lock --> jbd2_handle --> &ei->i_data_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->i_data_sem); lock(jbd2_handle); lock(&ei->i_data_sem); lock(&dquot->dq_lock); *** DEADLOCK *** 4 locks held by syz.8.2306/12490: #0: ffff0000e314a460 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3015 [inline] #0: ffff0000e314a460 (sb_writers#3){.+.+}-{0:0}, at: vfs_fallocate+0x434/0x5f4 fs/open.c:322 #1: ffff0000dfd5f258 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #1: ffff0000dfd5f258 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_fallocate+0x1e4/0x1b60 fs/ext4/extents.c:4785 #2: ffff0000dfd5f0e0 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x7c4/0x1770 fs/ext4/inode.c:672 #3: ffff80001538d648 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349 stack backtrace: CPU: 1 PID: 12490 Comm: syz.8.2306 Not tainted 6.1.142-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call trace: dump_backtrace+0x1c8/0x1f4 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+0xf8/0x160 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+0x240/0x2d4 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+0x293c/0x6544 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x1f38 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+0x50/0x1c4 fs/quota/dquot.c:507 ext4_write_dquot+0x1b4/0x31c fs/ext4/super.c:6790 ext4_mark_dquot_dirty+0xe8/0x140 fs/ext4/super.c:6867 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0x1f8/0x424 fs/quota/dquot.c:412 __dquot_alloc_space+0x560/0xce8 fs/quota/dquot.c:1752 dquot_alloc_space_nodirty include/linux/quotaops.h:300 [inline] dquot_alloc_space include/linux/quotaops.h:313 [inline] dquot_alloc_block include/linux/quotaops.h:337 [inline] ext4_mb_new_blocks+0xd30/0x435c fs/ext4/mballoc.c:5727 ext4_ext_map_blocks+0x1018/0x559c fs/ext4/extents.c:4340 ext4_map_blocks+0x860/0x1770 fs/ext4/inode.c:679 ext4_alloc_file_blocks+0x2ac/0x8e0 fs/ext4/extents.c:4524 ext4_fallocate+0x784/0x1b60 fs/ext4/extents.c:4811 vfs_fallocate+0x4a4/0x5f4 fs/open.c:323 ksys_fallocate fs/open.c:346 [inline] __do_sys_fallocate fs/open.c:354 [inline] __se_sys_fallocate fs/open.c:352 [inline] __arm64_sys_fallocate+0xc0/0x110 fs/open.c:352 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 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