====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.157/5045 is trying to acquire lock: ffff0000e191c700 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_get+0xec/0x554 fs/ext4/xattr.c:654 but task is already holding lock: ffff0000d9300c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ext_migrate+0x208/0xbf8 fs/ext4/migrate.c:437 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+0x1b0/0x28fc fs/ext4/inode.c:2717 do_writepages+0x2c4/0x50c mm/page-writeback.c:2491 __writeback_single_inode+0x164/0x157c fs/fs-writeback.c:1622 writeback_single_inode+0x1cc/0x73c fs/fs-writeback.c:1743 write_inode_now+0x150/0x1cc fs/fs-writeback.c:2786 iput_final fs/inode.c:1821 [inline] iput+0x5b8/0x7e8 fs/inode.c:1860 ext4_xattr_block_set+0x1eb0/0x28b4 fs/ext4/xattr.c:2095 ext4_xattr_move_to_block fs/ext4/xattr.c:2613 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2688 [inline] ext4_expand_extra_isize_ea+0xea4/0x1818 fs/ext4/xattr.c:2776 __ext4_expand_extra_isize+0x2a0/0x364 fs/ext4/inode.c:6003 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6046 [inline] __ext4_mark_inode_dirty+0x3d4/0x7b4 fs/ext4/inode.c:6124 ext4_evict_inode+0xb50/0x1264 fs/ext4/inode.c:281 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 -> #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+0x27c8/0x6610 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x638 kernel/locking/lockdep.c:5662 down_read+0x64/0x300 kernel/locking/rwsem.c:1520 ext4_xattr_get+0xec/0x554 fs/ext4/xattr.c:654 ext4_get_acl+0x94/0x640 fs/ext4/acl.c:165 get_acl+0x160/0x32c fs/posix_acl.c:153 posix_acl_create+0x104/0x3d0 fs/posix_acl.c:632 ext4_init_acl+0xb0/0x344 fs/ext4/acl.c:283 __ext4_new_inode+0x295c/0x3520 fs/ext4/ialloc.c:1333 ext4_ext_migrate+0x488/0xbf8 fs/ext4/migrate.c:455 __ext4_ioctl fs/ext4/ioctl.c:1399 [inline] ext4_ioctl+0x1b18/0x4384 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: 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 syz.2.157/5045: #0: ffff0000d9302460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write_file+0x64/0x1ec fs/namespace.c:446 #1: ffff0000e191de48 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #1: ffff0000e191de48 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: __ext4_ioctl fs/ext4/ioctl.c:1398 [inline] #1: ffff0000e191de48 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: ext4_ioctl+0x1b10/0x4384 fs/ext4/ioctl.c:1617 #2: ffff0000d9300c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ext_migrate+0x208/0xbf8 fs/ext4/migrate.c:437 stack backtrace: CPU: 1 PID: 5045 Comm: syz.2.157 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/02/2026 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:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x27c8/0x6610 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x638 kernel/locking/lockdep.c:5662 down_read+0x64/0x300 kernel/locking/rwsem.c:1520 ext4_xattr_get+0xec/0x554 fs/ext4/xattr.c:654 ext4_get_acl+0x94/0x640 fs/ext4/acl.c:165 get_acl+0x160/0x32c fs/posix_acl.c:153 posix_acl_create+0x104/0x3d0 fs/posix_acl.c:632 ext4_init_acl+0xb0/0x344 fs/ext4/acl.c:283 __ext4_new_inode+0x295c/0x3520 fs/ext4/ialloc.c:1333 ext4_ext_migrate+0x488/0xbf8 fs/ext4/migrate.c:455 __ext4_ioctl fs/ext4/ioctl.c:1399 [inline] ext4_ioctl+0x1b18/0x4384 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