====================================================== WARNING: possible circular locking dependency detected 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted ------------------------------------------------------ kswapd0/88 is trying to acquire lock: ffff88814c326d98 (&xfs_dir_ilock_class){++++}-{3:3}, at: xfs_reclaim_inode fs/xfs/xfs_icache.c:945 [inline] ffff88814c326d98 (&xfs_dir_ilock_class){++++}-{3:3}, at: xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1631 [inline] ffff88814c326d98 (&xfs_dir_ilock_class){++++}-{3:3}, at: xfs_icwalk_ag+0x1216/0x1aa0 fs/xfs/xfs_icache.c:1713 but task is already holding lock: ffffffff8e21f720 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6774 [inline] ffffffff8e21f720 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xb3f/0x36e0 mm/vmscan.c:7146 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (fs_reclaim){+.+.}-{0:0}: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __fs_reclaim_acquire mm/page_alloc.c:3692 [inline] fs_reclaim_acquire+0x88/0x130 mm/page_alloc.c:3706 might_alloc include/linux/sched/mm.h:303 [inline] slab_pre_alloc_hook mm/slub.c:3746 [inline] slab_alloc_node mm/slub.c:3827 [inline] kmem_cache_alloc+0x48/0x340 mm/slub.c:3852 radix_tree_node_alloc+0x8b/0x3c0 lib/radix-tree.c:276 radix_tree_extend+0x148/0x5c0 lib/radix-tree.c:425 __radix_tree_create lib/radix-tree.c:613 [inline] radix_tree_insert+0x15c/0x680 lib/radix-tree.c:712 xfs_qm_dqget_cache_insert fs/xfs/xfs_dquot.c:826 [inline] xfs_qm_dqget+0x2d4/0x640 fs/xfs/xfs_dquot.c:901 xfs_qm_vop_dqalloc+0x913/0xef0 fs/xfs/xfs_qm.c:1773 xfs_fileattr_set+0x3ff/0x1920 fs/xfs/xfs_ioctl.c:1347 vfs_fileattr_set+0x901/0xd50 fs/ioctl.c:697 ioctl_fssetxattr fs/ioctl.c:759 [inline] do_vfs_ioctl+0x1a9c/0x2e50 fs/ioctl.c:873 __do_sys_ioctl fs/ioctl.c:902 [inline] __se_sys_ioctl+0x81/0x170 fs/ioctl.c:890 do_syscall_64+0xfd/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 -> #1 (&qinf->qi_tree_lock){+.+.}-{3:3}: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 xfs_qm_dqget_cache_lookup+0x30/0x870 fs/xfs/xfs_dquot.c:784 xfs_qm_dqget_inode+0x353/0xaa0 fs/xfs/xfs_dquot.c:986 xfs_qm_dqattach_one+0x185/0x5e0 fs/xfs/xfs_qm.c:278 xfs_qm_dqattach_locked+0x3d1/0x4e0 fs/xfs/xfs_qm.c:329 xfs_qm_vop_dqalloc+0x3fd/0xef0 fs/xfs/xfs_qm.c:1710 xfs_fileattr_set+0x3ff/0x1920 fs/xfs/xfs_ioctl.c:1347 vfs_fileattr_set+0x901/0xd50 fs/ioctl.c:697 ioctl_fssetxattr fs/ioctl.c:759 [inline] do_vfs_ioctl+0x1a9c/0x2e50 fs/ioctl.c:873 __do_sys_ioctl fs/ioctl.c:902 [inline] __se_sys_ioctl+0x81/0x170 fs/ioctl.c:890 do_syscall_64+0xfd/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 -> #0 (&xfs_dir_ilock_class){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 down_write_nested+0x3d/0x50 kernel/locking/rwsem.c:1695 xfs_reclaim_inode fs/xfs/xfs_icache.c:945 [inline] xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1631 [inline] xfs_icwalk_ag+0x1216/0x1aa0 fs/xfs/xfs_icache.c:1713 xfs_icwalk fs/xfs/xfs_icache.c:1762 [inline] xfs_reclaim_inodes_nr+0x257/0x360 fs/xfs/xfs_icache.c:1011 super_cache_scan+0x411/0x4b0 fs/super.c:227 do_shrink_slab+0x6d2/0x1140 mm/shrinker.c:435 shrink_slab+0x1092/0x14d0 mm/shrinker.c:662 shrink_one+0x423/0x7f0 mm/vmscan.c:4767 shrink_many mm/vmscan.c:4828 [inline] lru_gen_shrink_node mm/vmscan.c:4929 [inline] shrink_node+0x37b8/0x3e70 mm/vmscan.c:5888 kswapd_shrink_node mm/vmscan.c:6696 [inline] balance_pgdat mm/vmscan.c:6886 [inline] kswapd+0x17d1/0x36e0 mm/vmscan.c:7146 kthread+0x2f2/0x390 kernel/kthread.c:388 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 other info that might help us debug this: Chain exists of: &xfs_dir_ilock_class --> &qinf->qi_tree_lock --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&qinf->qi_tree_lock); lock(fs_reclaim); lock(&xfs_dir_ilock_class); *** DEADLOCK *** 2 locks held by kswapd0/88: #0: ffffffff8e21f720 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6774 [inline] #0: ffffffff8e21f720 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xb3f/0x36e0 mm/vmscan.c:7146 #1: ffff888078b540e0 (&type->s_umount_key#60){++++}-{3:3}, at: super_trylock_shared fs/super.c:561 [inline] #1: ffff888078b540e0 (&type->s_umount_key#60){++++}-{3:3}, at: super_cache_scan+0x94/0x4b0 fs/super.c:196 stack backtrace: CPU: 0 PID: 88 Comm: kswapd0 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 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+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 down_write_nested+0x3d/0x50 kernel/locking/rwsem.c:1695 xfs_reclaim_inode fs/xfs/xfs_icache.c:945 [inline] xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1631 [inline] xfs_icwalk_ag+0x1216/0x1aa0 fs/xfs/xfs_icache.c:1713 xfs_icwalk fs/xfs/xfs_icache.c:1762 [inline] xfs_reclaim_inodes_nr+0x257/0x360 fs/xfs/xfs_icache.c:1011 super_cache_scan+0x411/0x4b0 fs/super.c:227 do_shrink_slab+0x6d2/0x1140 mm/shrinker.c:435 shrink_slab+0x1092/0x14d0 mm/shrinker.c:662 shrink_one+0x423/0x7f0 mm/vmscan.c:4767 shrink_many mm/vmscan.c:4828 [inline] lru_gen_shrink_node mm/vmscan.c:4929 [inline] shrink_node+0x37b8/0x3e70 mm/vmscan.c:5888 kswapd_shrink_node mm/vmscan.c:6696 [inline] balance_pgdat mm/vmscan.c:6886 [inline] kswapd+0x17d1/0x36e0 mm/vmscan.c:7146 kthread+0x2f2/0x390 kernel/kthread.c:388 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243