EXT4-fs (loop9): mounted filesystem without journal. Quota mode: writeback. ext4 filesystem being mounted at /56/bus supports timestamps until 2038-01-19 (0x7fffffff) ====================================================== WARNING: possible circular locking dependency detected 6.1.142-syzkaller #0 Not tainted ------------------------------------------------------ syz.9.753/7530 is trying to acquire lock: ffff8880597c9698 (&ei->i_data_sem/1){+.+.}-{3:3}, at: ext4_move_extents+0x325/0xb90 fs/ext4/move_extent.c:615 but task is already holding lock: ffff8880597c8c90 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_double_down_write_data_sem+0x28/0x40 fs/ext4/move_extent.c:-1 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ei->i_data_sem/2){++++}-{3:3}: down_write+0x36/0x60 kernel/locking/rwsem.c:1573 ext4_map_blocks+0x903/0x1b60 fs/ext4/inode.c:672 ext4_getblk+0x1ab/0x6d0 fs/ext4/inode.c:890 ext4_bread+0x26/0x170 fs/ext4/inode.c:946 ext4_quota_write+0x230/0x570 fs/ext4/super.c:7201 write_blk fs/quota/quota_tree.c:70 [inline] find_free_dqentry+0x673/0xc20 fs/quota/quota_tree.c:318 do_insert_tree+0x70d/0x1040 fs/quota/quota_tree.c:400 do_insert_tree+0x9ae/0x1040 fs/quota/quota_tree.c:402 do_insert_tree+0x9ae/0x1040 fs/quota/quota_tree.c:402 do_insert_tree+0x9ae/0x1040 fs/quota/quota_tree.c:402 dq_insert_tree fs/quota/quota_tree.c:432 [inline] qtree_write_dquot+0x48d/0x5b0 fs/quota/quota_tree.c:451 v2_write_dquot+0x108/0x190 fs/quota/quota_v2.c:361 dquot_acquire+0x2d5/0x520 fs/quota/dquot.c:472 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6810 dqget+0x778/0xeb0 fs/quota/dquot.c:988 dquot_set_dqblk+0x27/0xf90 fs/quota/dquot.c:2833 quota_setquota+0x4ac/0x530 fs/quota/quota.c:310 __do_sys_quotactl fs/quota/quota.c:960 [inline] __se_sys_quotactl+0x295/0x6b0 fs/quota/quota.c:916 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #2 (&s->s_dquot.dqio_sem){++++}-{3:3}: down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520 v2_read_dquot+0x4a/0x110 fs/quota/quota_v2.c:335 dquot_acquire+0x152/0x520 fs/quota/dquot.c:463 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6810 dqget+0x778/0xeb0 fs/quota/dquot.c:988 dquot_set_dqblk+0x27/0xf90 fs/quota/dquot.c:2833 quota_setquota+0x4ac/0x530 fs/quota/quota.c:310 __do_sys_quotactl fs/quota/quota.c:960 [inline] __se_sys_quotactl+0x295/0x6b0 fs/quota/quota.c:916 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #1 (&dquot->dq_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747 dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6790 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412 __dquot_alloc_space+0x5fc/0xe60 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+0xf74/0x4720 fs/ext4/mballoc.c:5727 ext4_new_meta_blocks+0x151/0x3a0 fs/ext4/balloc.c:739 ext4_ext_grow_indepth fs/ext4/extents.c:1331 [inline] ext4_ext_create_new_leaf fs/ext4/extents.c:1437 [inline] ext4_ext_insert_extent+0x1048/0x4740 fs/ext4/extents.c:2105 ext4_split_extent_at+0x7d3/0xf80 fs/ext4/extents.c:3236 ext4_force_split_extent_at fs/ext4/extents.c:338 [inline] ext4_swap_extents+0xda2/0x1c90 fs/ext4/extents.c:5747 move_extent_per_page+0x1f63/0x47e0 fs/ext4/move_extent.c:367 ext4_move_extents+0x89a/0xb90 fs/ext4/move_extent.c:678 __ext4_ioctl fs/ext4/ioctl.c:1358 [inline] ext4_ioctl+0x3501/0x3dd0 fs/ext4/ioctl.c:1614 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&ei->i_data_sem/1){+.+.}-{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+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 down_write_nested+0x39/0x60 kernel/locking/rwsem.c:1689 ext4_move_extents+0x325/0xb90 fs/ext4/move_extent.c:615 __ext4_ioctl fs/ext4/ioctl.c:1358 [inline] ext4_ioctl+0x3501/0x3dd0 fs/ext4/ioctl.c:1614 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 other info that might help us debug this: Chain exists of: &ei->i_data_sem/1 --> &s->s_dquot.dqio_sem --> &ei->i_data_sem/2 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->i_data_sem/2); lock(&s->s_dquot.dqio_sem); lock(&ei->i_data_sem/2); lock(&ei->i_data_sem/1); *** DEADLOCK *** 4 locks held by syz.9.753/7530: #0: ffff88807787c460 (sb_writers#4){++++}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:437 #1: ffff8880597c8e08 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #1: ffff8880597c8e08 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: lock_two_nondirectories+0xd5/0x150 fs/inode.c:1208 #2: ffff8880597c9810 (&sb->s_type->i_mutex_key#8/4){+.+.}-{3:3}, at: ext4_move_extents+0x30a/0xb90 fs/ext4/move_extent.c:608 #3: ffff8880597c8c90 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_double_down_write_data_sem+0x28/0x40 fs/ext4/move_extent.c:-1 stack backtrace: CPU: 1 PID: 7530 Comm: syz.9.753 Not tainted 6.1.142-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 check_noncircular+0x274/0x310 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+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 down_write_nested+0x39/0x60 kernel/locking/rwsem.c:1689 ext4_move_extents+0x325/0xb90 fs/ext4/move_extent.c:615 __ext4_ioctl fs/ext4/ioctl.c:1358 [inline] ext4_ioctl+0x3501/0x3dd0 fs/ext4/ioctl.c:1614 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f914e58e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f914f4b2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f914e7b5fa0 RCX: 00007f914e58e929 RDX: 0000200000000240 RSI: 00000000c028660f RDI: 0000000000000006 RBP: 00007f914e610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f914e7b5fa0 R15: 00007ffdc5232a78