============================================ WARNING: possible recursive locking detected 6.4.0-rc3-syzkaller #0 Not tainted -------------------------------------------- kworker/u4:3/55 is trying to acquire lock: ffff8880763940b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x14a/0x1c0 but task is already holding lock: ffff8880763940b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x14a/0x1c0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&tree->tree_lock/1); lock(&tree->tree_lock/1); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by kworker/u4:3/55: #0: ffff888145195938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x77e/0x10e0 kernel/workqueue.c:2378 #1: ffffc90001567d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7c8/0x10e0 kernel/workqueue.c:2380 #2: ffff88807a138108 (&hip->extents_lock){+.+.}-{3:3}, at: hfsplus_ext_write_extent+0x8e/0x1f0 fs/hfsplus/extents.c:149 #3: ffff8880763940b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x14a/0x1c0 #4: ffff888076398108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_extend+0x1d6/0x1b10 fs/hfsplus/extents.c:457 stack backtrace: CPU: 0 PID: 55 Comm: kworker/u4:3 Not tainted 6.4.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:3001 [inline] check_deadlock kernel/locking/lockdep.c:3044 [inline] validate_chain+0x472a/0x58e0 kernel/locking/lockdep.c:3829 __lock_acquire+0x1295/0x2000 kernel/locking/lockdep.c:5074 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691 __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799 hfsplus_find_init+0x14a/0x1c0 hfsplus_ext_read_extent fs/hfsplus/extents.c:216 [inline] hfsplus_file_extend+0x40e/0x1b10 fs/hfsplus/extents.c:461 hfsplus_bmap_reserve+0x105/0x4e0 fs/hfsplus/btree.c:358 __hfsplus_ext_write_extent+0x2a4/0x5b0 fs/hfsplus/extents.c:104 hfsplus_ext_write_extent_locked fs/hfsplus/extents.c:139 [inline] hfsplus_ext_write_extent+0x16a/0x1f0 fs/hfsplus/extents.c:150 hfsplus_write_inode+0x22/0x5e0 fs/hfsplus/super.c:154 write_inode fs/fs-writeback.c:1456 [inline] __writeback_single_inode+0x69b/0xfa0 fs/fs-writeback.c:1668 writeback_sb_inodes+0x8e3/0x11d0 fs/fs-writeback.c:1894 wb_writeback+0x458/0xc70 fs/fs-writeback.c:2068 wb_do_writeback fs/fs-writeback.c:2211 [inline] wb_workfn+0x400/0xff0 fs/fs-writeback.c:2251 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2405 worker_thread+0xa63/0x1210 kernel/workqueue.c:2552 kthread+0x2b8/0x350 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308