====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:10/5724 is trying to acquire lock: ffff0000d7bd1ee0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ffff0000d7bd1ee0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_destroy_inline_data+0x30/0x11c fs/ext4/inline.c:1912 but task is already holding lock: ffff0000d5feeb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x188/0x284c fs/ext4/inode.c:2715 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sbi->s_writepages_rwsem){.+.+}-{0:0}: percpu_down_read+0x70/0x2a8 include/linux/percpu-rwsem.h:51 ext4_writepages+0x188/0x284c fs/ext4/inode.c:2715 do_writepages+0x2c0/0x4fc mm/page-writeback.c:2491 __writeback_single_inode+0x164/0x157c fs/fs-writeback.c:1622 writeback_single_inode+0x1c0/0x720 fs/fs-writeback.c:1743 write_inode_now+0x144/0x1b0 fs/fs-writeback.c:2780 iput_final fs/inode.c:1821 [inline] iput+0x5cc/0x7f4 fs/inode.c:1860 ext4_xattr_block_set+0x17a4/0x2810 fs/ext4/xattr.c:2158 ext4_xattr_move_to_block fs/ext4/xattr.c:2626 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2701 [inline] ext4_expand_extra_isize_ea+0xcb8/0x15cc fs/ext4/xattr.c:2793 __ext4_expand_extra_isize+0x298/0x358 fs/ext4/inode.c:5980 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6023 [inline] __ext4_mark_inode_dirty+0x3e4/0x790 fs/ext4/inode.c:6101 ext4_evict_inode+0xb58/0x1270 fs/ext4/inode.c:279 evict+0x3c8/0x810 fs/inode.c:705 iput_final fs/inode.c:1834 [inline] iput+0x764/0x7f4 fs/inode.c:1860 ext4_process_orphan+0x240/0x2b4 fs/ext4/orphan.c:356 ext4_orphan_cleanup+0x908/0x104c fs/ext4/orphan.c:470 __ext4_fill_super fs/ext4/super.c:5530 [inline] ext4_fill_super+0x6440/0x68a8 fs/ext4/super.c:5661 get_tree_bdev+0x358/0x544 fs/super.c:1366 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5691 vfs_get_tree+0x90/0x274 fs/super.c:1573 do_new_mount+0x228/0x810 fs/namespace.c:3078 path_mount+0x5b4/0xe78 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+0x49c/0x584 fs/namespace.c:3606 __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 (&ei->xattr_sem){++++}-{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 down_write+0x5c/0x88 kernel/locking/rwsem.c:1573 ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ext4_destroy_inline_data+0x30/0x11c fs/ext4/inline.c:1912 ext4_writepages+0x3f4/0x284c fs/ext4/inode.c:2761 do_writepages+0x2c0/0x4fc mm/page-writeback.c:2491 __writeback_single_inode+0x164/0x157c fs/fs-writeback.c:1622 writeback_sb_inodes+0x824/0x1404 fs/fs-writeback.c:1913 wb_writeback+0x400/0xfb0 fs/fs-writeback.c:2087 wb_do_writeback fs/fs-writeback.c:2230 [inline] wb_workfn+0x34c/0xd98 fs/fs-writeback.c:2270 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:850 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sbi->s_writepages_rwsem); lock(&ei->xattr_sem); lock(&sbi->s_writepages_rwsem); lock(&ei->xattr_sem); *** DEADLOCK *** 3 locks held by kworker/u4:10/5724: #0: ffff0000c0c48938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x6b4/0x13a8 kernel/workqueue.c:2265 #1: ffff800021747c20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6f8/0x13a8 kernel/workqueue.c:2267 #2: ffff0000d5feeb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x188/0x284c fs/ext4/inode.c:2715 stack backtrace: CPU: 0 PID: 5724 Comm: kworker/u4:10 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025 Workqueue: writeback wb_workfn (flush-7:5) 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 down_write+0x5c/0x88 kernel/locking/rwsem.c:1573 ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ext4_destroy_inline_data+0x30/0x11c fs/ext4/inline.c:1912 ext4_writepages+0x3f4/0x284c fs/ext4/inode.c:2761 do_writepages+0x2c0/0x4fc mm/page-writeback.c:2491 __writeback_single_inode+0x164/0x157c fs/fs-writeback.c:1622 writeback_sb_inodes+0x824/0x1404 fs/fs-writeback.c:1913 wb_writeback+0x400/0xfb0 fs/fs-writeback.c:2087 wb_do_writeback fs/fs-writeback.c:2230 [inline] wb_workfn+0x34c/0xd98 fs/fs-writeback.c:2270 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:850 EXT4-fs error (device loop5): ext4_mb_generate_buddy:1097: group 0, block bitmap and bg descriptor inconsistent: 25 vs 4278190105 free clusters EXT4-fs (loop5): Delayed block allocation failed for inode 15 at logical offset 0 with max blocks 1 with error 28 EXT4-fs (loop5): This should not happen!! Data will be lost EXT4-fs (loop5): Total free blocks count 0 EXT4-fs (loop5): Free/Dirty block details EXT4-fs (loop5): free_blocks=68451041280 EXT4-fs (loop5): dirty_blocks=32 EXT4-fs (loop5): Block reservation details EXT4-fs (loop5): i_reserved_data_blocks=2 IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_0: link becomes ready bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered forwarding state IPv6: ADDRCONF(NETDEV_CHANGE): bridge0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): macvlan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): macvlan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1_macvtap: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0_macvtap: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): macvtap0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): macsec0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready