EXT4-fs (loop1): mounted filesystem without journal. Quota mode: writeback. ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.1.528/6586 is trying to acquire lock: ffff0000f546d2c8 (&ei->i_data_sem/1){+.+.}-{3:3}, at: ext4_double_down_write_data_sem+0x3c/0x4c fs/ext4/move_extent.c:-1 but task is already holding lock: ffff0000f546c8c0 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_double_down_write_data_sem+0x30/0x4c 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+0x5c/0x88 kernel/locking/rwsem.c:1573 ext4_map_blocks+0x720/0x160c fs/ext4/inode.c:674 ext4_getblk+0x178/0x680 fs/ext4/inode.c:892 ext4_bread+0x3c/0x1a8 fs/ext4/inode.c:948 ext4_quota_write+0x200/0x544 fs/ext4/super.c:7228 write_blk fs/quota/quota_tree.c:70 [inline] find_free_dqentry+0x55c/0xa8c fs/quota/quota_tree.c:318 do_insert_tree+0x5c0/0xc68 fs/quota/quota_tree.c:400 do_insert_tree+0x7dc/0xc68 fs/quota/quota_tree.c:402 do_insert_tree+0x7dc/0xc68 fs/quota/quota_tree.c:402 do_insert_tree+0x7dc/0xc68 fs/quota/quota_tree.c:402 dq_insert_tree fs/quota/quota_tree.c:432 [inline] qtree_write_dquot+0x3d4/0x4e4 fs/quota/quota_tree.c:451 v2_write_dquot+0xf0/0x180 fs/quota/quota_v2.c:361 dquot_acquire+0x280/0x4b8 fs/quota/dquot.c:497 ext4_acquire_dquot+0x270/0x420 fs/ext4/super.c:6837 dqget+0x638/0xa98 fs/quota/dquot.c:1010 __dquot_initialize+0x2e4/0xb30 fs/quota/dquot.c:1539 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1601 ext4_process_orphan+0x5c/0x2c0 fs/ext4/orphan.c:327 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 -> #2 (&s->s_dquot.dqio_sem){++++}-{3:3}: down_read+0x64/0x300 kernel/locking/rwsem.c:1520 v2_read_dquot+0x4c/0x118 fs/quota/quota_v2.c:335 dquot_acquire+0x108/0x4b8 fs/quota/dquot.c:488 ext4_acquire_dquot+0x270/0x420 fs/ext4/super.c:6837 dqget+0x638/0xa98 fs/quota/dquot.c:1010 __dquot_initialize+0x2e4/0xb30 fs/quota/dquot.c:1539 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1601 ext4_process_orphan+0x5c/0x2c0 fs/ext4/orphan.c:327 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 (&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:532 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:397 [inline] mark_all_dquot_dirty+0x108/0x424 fs/quota/dquot.c:437 __dquot_free_space+0x768/0xaa4 fs/quota/dquot.c:1964 dquot_free_space_nodirty include/linux/quotaops.h:372 [inline] dquot_free_space+0x2c/0x48 include/linux/quotaops.h:377 swap_inode_boot_loader+0x868/0xc3c fs/ext4/ioctl.c:492 __ext4_ioctl fs/ext4/ioctl.c:1427 [inline] ext4_ioctl+0x1b3c/0x4384 fs/ext4/ioctl.c:1617 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __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 -> #0 (&ei->i_data_sem/1){+.+.}-{3:3}: 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 down_write_nested+0x64/0x94 kernel/locking/rwsem.c:1689 ext4_double_down_write_data_sem+0x3c/0x4c fs/ext4/move_extent.c:-1 swap_inode_boot_loader+0x3e4/0xc3c fs/ext4/ioctl.c:426 __ext4_ioctl fs/ext4/ioctl.c:1427 [inline] ext4_ioctl+0x1b3c/0x4384 fs/ext4/ioctl.c:1617 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __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 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 *** 5 locks held by syz.1.528/6586: #0: ffff0000d2b40460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write_file+0x64/0x1ec fs/namespace.c:446 #1: ffff0000f546ca38 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #1: ffff0000f546ca38 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: lock_two_nondirectories+0xd0/0x128 fs/inode.c:1208 #2: ffff0000f546d440 (&sb->s_type->i_mutex_key#10/4){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline] #2: ffff0000f546d440 (&sb->s_type->i_mutex_key#10/4){+.+.}-{3:3}, at: lock_two_nondirectories+0xb8/0x128 fs/inode.c:1210 #3: ffff0000f546d5e0 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:803 [inline] #3: ffff0000f546d5e0 (mapping.invalidate_lock#2){++++}-{3:3}, at: swap_inode_boot_loader+0x278/0xc3c fs/ext4/ioctl.c:402 #4: ffff0000f546c8c0 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_double_down_write_data_sem+0x30/0x4c fs/ext4/move_extent.c:-1 stack backtrace: CPU: 1 PID: 6586 Comm: syz.1.528 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026 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 down_write_nested+0x64/0x94 kernel/locking/rwsem.c:1689 ext4_double_down_write_data_sem+0x3c/0x4c fs/ext4/move_extent.c:-1 swap_inode_boot_loader+0x3e4/0xc3c fs/ext4/ioctl.c:426 __ext4_ioctl fs/ext4/ioctl.c:1427 [inline] ext4_ioctl+0x1b3c/0x4384 fs/ext4/ioctl.c:1617 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __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