====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:9/16265 is trying to acquire lock: ffff888053d834f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xff/0x1380 fs/hfs/extent.c:397 but task is already holding lock: ffff888030e580b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x17e/0x1f0 fs/hfs/bfind.c:-1 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&tree->tree_lock/1){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x136/0xcc0 kernel/locking/mutex.c:747 hfs_find_init+0x17e/0x1f0 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x361/0x1380 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 hfs_cat_create+0x1fe/0x6b0 fs/hfs/catalog.c:104 hfs_mkdir+0x6c/0xe0 fs/hfs/dir.c:232 vfs_mkdir+0x296/0x440 fs/namei.c:4121 do_mkdirat+0x1dc/0x450 fs/namei.c:4144 __do_sys_mkdirat fs/namei.c:4159 [inline] __se_sys_mkdirat fs/namei.c:4157 [inline] __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4157 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&HFS_I(tree->inode)->extents_lock){+.+.}-{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+0x2df1/0x7d40 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x136/0xcc0 kernel/locking/mutex.c:747 hfs_extend_file+0xff/0x1380 fs/hfs/extent.c:397 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121 hfs_ext_write_extent+0x17f/0x210 fs/hfs/extent.c:144 hfs_write_inode+0xdc/0x880 fs/hfs/inode.c:434 write_inode fs/fs-writeback.c:1483 [inline] __writeback_single_inode+0x705/0xec0 fs/fs-writeback.c:1700 writeback_sb_inodes+0x7cd/0xf50 fs/fs-writeback.c:1926 wb_writeback+0x46a/0xbf0 fs/fs-writeback.c:2105 wb_do_writeback fs/fs-writeback.c:2252 [inline] wb_workfn+0x400/0xe60 fs/fs-writeback.c:2292 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&tree->tree_lock/1); lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock/1); lock(&HFS_I(tree->inode)->extents_lock); *** DEADLOCK *** 3 locks held by kworker/u4:9/16265: #0: ffff88801a646938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff88801a646938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711 #1: ffffc90003497d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90003497d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711 #2: ffff888030e580b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x17e/0x1f0 fs/hfs/bfind.c:-1 stack backtrace: CPU: 0 PID: 16265 Comm: kworker/u4:9 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: writeback wb_workfn (flush-7:3) Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 check_noncircular+0x2fc/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+0x2df1/0x7d40 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x136/0xcc0 kernel/locking/mutex.c:747 hfs_extend_file+0xff/0x1380 fs/hfs/extent.c:397 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121 hfs_ext_write_extent+0x17f/0x210 fs/hfs/extent.c:144 hfs_write_inode+0xdc/0x880 fs/hfs/inode.c:434 write_inode fs/fs-writeback.c:1483 [inline] __writeback_single_inode+0x705/0xec0 fs/fs-writeback.c:1700 writeback_sb_inodes+0x7cd/0xf50 fs/fs-writeback.c:1926 wb_writeback+0x46a/0xbf0 fs/fs-writeback.c:2105 wb_do_writeback fs/fs-writeback.c:2252 [inline] wb_workfn+0x400/0xe60 fs/fs-writeback.c:2292 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 IPVS: Schedule: port zero only supported in persistent services, check your ipvs configuration