============================================ WARNING: possible recursive locking detected syzkaller #0 Not tainted -------------------------------------------- syz.3.140/5042 is trying to acquire lock: ffff0000c44ae0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x148/0x1c8 fs/hfs/bfind.c:-1 but task is already holding lock: ffff0000c44ae0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x148/0x1c8 fs/hfs/bfind.c:-1 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 syz.3.140/5042: #0: ffff0000fb776460 (sb_writers#23){.+.+}-{0:0}, at: vfs_writev fs/read_write.c:933 [inline] #0: ffff0000fb776460 (sb_writers#23){.+.+}-{0:0}, at: do_pwritev+0x1b4/0x2fc fs/read_write.c:1031 #1: ffff0000d9431628 (&sb->s_type->i_mutex_key#28){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #1: ffff0000d9431628 (&sb->s_type->i_mutex_key#28){+.+.}-{3:3}, at: generic_file_write_iter+0x84/0x2b0 mm/filemap.c:4003 #2: ffff0000d9431478 (&HFS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xd4/0xf9c fs/hfs/extent.c:397 #3: ffff0000c44ae0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x148/0x1c8 fs/hfs/bfind.c:-1 #4: ffff0000d94300f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xd4/0xf9c fs/hfs/extent.c:397 stack backtrace: CPU: 1 PID: 5042 Comm: syz.3.140 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025 Call trace: dump_backtrace+0x1c8/0x1f4 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+0xf8/0x160 lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 __lock_acquire+0x18b4/0x6544 kernel/locking/lockdep.c:-1 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x1f38 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 hfs_find_init+0x148/0x1c8 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x238/0xf9c fs/hfs/extent.c:401 hfs_bmap_reserve+0xd4/0x3e0 fs/hfs/btree.c:234 __hfs_ext_write_extent+0x19c/0x488 fs/hfs/extent.c:121 __hfs_ext_cache_extent+0x84/0x750 fs/hfs/extent.c:174 hfs_ext_read_extent fs/hfs/extent.c:202 [inline] hfs_extend_file+0x264/0xf9c fs/hfs/extent.c:401 hfs_get_block+0x2e8/0x9cc fs/hfs/extent.c:353 __block_write_begin_int+0x34c/0x13b8 fs/buffer.c:1991 __block_write_begin fs/buffer.c:2041 [inline] block_write_begin fs/buffer.c:2102 [inline] cont_write_begin+0x548/0x780 fs/buffer.c:2456 hfs_write_begin+0x98/0xe4 fs/hfs/inode.c:58 cont_expand_zero fs/buffer.c:2383 [inline] cont_write_begin+0x268/0x780 fs/buffer.c:2446 hfs_write_begin+0x98/0xe4 fs/hfs/inode.c:58 generic_perform_write+0x230/0x4b0 mm/filemap.c:3846 __generic_file_write_iter+0x168/0x37c mm/filemap.c:3974 generic_file_write_iter+0xb4/0x2b0 mm/filemap.c:4006 do_iter_readv_writev fs/read_write.c:-1 [inline] do_iter_write+0x530/0x91c fs/read_write.c:861 vfs_writev fs/read_write.c:934 [inline] do_pwritev+0x1c8/0x2fc fs/read_write.c:1031 __do_sys_pwritev2 fs/read_write.c:1090 [inline] __se_sys_pwritev2 fs/read_write.c:1081 [inline] __arm64_sys_pwritev2+0xd4/0x108 fs/read_write.c:1081 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 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