====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc4-syzkaller-00283-g563a50672d8a #0 Not tainted ------------------------------------------------------ kswapd0/111 is trying to acquire lock: ffff88804bb10118 (&xfs_nondir_ilock_class#3){++++}-{3:3}, at: xfs_ilock+0x2ef/0x420 fs/xfs/xfs_inode.c:207 but task is already holding lock: ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x166/0x1970 mm/vmscan.c:6798 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}-{0:0}: __fs_reclaim_acquire mm/page_alloc.c:3801 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3891 [inline] slab_alloc_node mm/slub.c:3981 [inline] __do_kmalloc_node mm/slub.c:4121 [inline] __kmalloc_noprof+0xb5/0x420 mm/slub.c:4135 kmalloc_noprof include/linux/slab.h:664 [inline] xfs_attr_shortform_list fs/xfs/xfs_attr_list.c:117 [inline] xfs_attr_list_ilocked+0x9a0/0x1b00 fs/xfs/xfs_attr_list.c:569 xfs_attr_list+0x1f9/0x2b0 fs/xfs/xfs_attr_list.c:595 xfs_vn_listxattr+0x11f/0x1c0 fs/xfs/xfs_xattr.c:324 vfs_listxattr+0xb7/0x140 fs/xattr.c:493 ovl_copy_xattr+0x1db/0xcb0 fs/overlayfs/copy_up.c:98 ovl_copy_up_metadata+0x1ad/0x760 fs/overlayfs/copy_up.c:650 ovl_copy_up_tmpfile fs/overlayfs/copy_up.c:870 [inline] ovl_do_copy_up fs/overlayfs/copy_up.c:976 [inline] ovl_copy_up_one+0x1b12/0x3490 fs/overlayfs/copy_up.c:1168 ovl_copy_up_flags+0x18d/0x200 fs/overlayfs/copy_up.c:1223 ovl_link+0x31/0x220 fs/overlayfs/dir.c:716 vfs_link+0x83e/0xe50 fs/namei.c:4613 do_linkat+0x533/0x5e0 fs/namei.c:4683 __do_sys_link fs/namei.c:4717 [inline] __se_sys_link fs/namei.c:4715 [inline] __ia32_sys_link+0x80/0xa0 fs/namei.c:4715 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #0 (&xfs_nondir_ilock_class #3 ){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 down_write_nested+0x3d/0x50 kernel/locking/rwsem.c:1695 xfs_ilock+0x2ef/0x420 fs/xfs/xfs_inode.c:207 xfs_reclaim_inode fs/xfs/xfs_icache.c:943 [inline] xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1629 [inline] xfs_icwalk_ag+0xca6/0x1780 fs/xfs/xfs_icache.c:1711 xfs_icwalk+0x57/0x100 fs/xfs/xfs_icache.c:1760 xfs_reclaim_inodes_nr+0x182/0x250 fs/xfs/xfs_icache.c:1009 super_cache_scan+0x409/0x550 fs/super.c:227 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab+0x18a/0x1310 mm/shrinker.c:662 shrink_one+0x493/0x7c0 mm/vmscan.c:4790 shrink_many mm/vmscan.c:4851 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951 shrink_node mm/vmscan.c:5910 [inline] kswapd_shrink_node mm/vmscan.c:6720 [inline] balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911 kswapd+0x5ea/0xbf0 mm/vmscan.c:7180 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&xfs_nondir_ilock_class#3); lock(fs_reclaim); lock(&xfs_nondir_ilock_class#3); *** DEADLOCK *** 2 locks held by kswapd0/111: #0: ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x166/0x1970 mm/vmscan.c:6798 #1: ffff888021d600e0 (&type->s_umount_key#74){++++}-{3:3}, at: super_trylock_shared fs/super.c:562 [inline] #1: ffff888021d600e0 (&type->s_umount_key#74){++++}-{3:3}, at: super_cache_scan+0x96/0x550 fs/super.c:196 stack backtrace: CPU: 2 PID: 111 Comm: kswapd0 Not tainted 6.10.0-rc4-syzkaller-00283-g563a50672d8a #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 down_write_nested+0x3d/0x50 kernel/locking/rwsem.c:1695 xfs_ilock+0x2ef/0x420 fs/xfs/xfs_inode.c:207 xfs_reclaim_inode fs/xfs/xfs_icache.c:943 [inline] xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1629 [inline] xfs_icwalk_ag+0xca6/0x1780 fs/xfs/xfs_icache.c:1711 xfs_icwalk+0x57/0x100 fs/xfs/xfs_icache.c:1760 xfs_reclaim_inodes_nr+0x182/0x250 fs/xfs/xfs_icache.c:1009 super_cache_scan+0x409/0x550 fs/super.c:227 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab+0x18a/0x1310 mm/shrinker.c:662 shrink_one+0x493/0x7c0 mm/vmscan.c:4790 shrink_many mm/vmscan.c:4851 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951 shrink_node mm/vmscan.c:5910 [inline] kswapd_shrink_node mm/vmscan.c:6720 [inline] balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911 kswapd+0x5ea/0xbf0 mm/vmscan.c:7180 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244