======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
kworker/u8:36/7193 is trying to acquire lock:
ffff888063c65b98 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xf9/0x1680 fs/hfs/extent.c:397
but task is already holding lock:
ffff88804009a0a0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x18d/0x300 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){+.+.}-{4:4}:
__mutex_lock_common kernel/locking/rtmutex_api.c:561 [inline]
mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:580
hfs_find_init+0x18d/0x300 fs/hfs/bfind.c:-1
hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
hfs_extend_file+0x367/0x1680 fs/hfs/extent.c:401
hfs_bmap_reserve+0x108/0x430 fs/hfs/btree.c:399
hfs_cat_create+0x23d/0x870 fs/hfs/catalog.c:104
hfs_mkdir+0x73/0xe0 fs/hfs/dir.c:226
vfs_mkdir+0x408/0x620 fs/namei.c:5410
filename_mkdirat+0x289/0x520 fs/namei.c:5443
__do_sys_mkdirat fs/namei.c:5464 [inline]
__se_sys_mkdirat+0x35/0x150 fs/namei.c:5461
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}:
check_prev_add kernel/locking/lockdep.c:3209 [inline]
check_prevs_add kernel/locking/lockdep.c:3328 [inline]
validate_chain kernel/locking/lockdep.c:3952 [inline]
__lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288
lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
__mutex_lock_common kernel/locking/rtmutex_api.c:561 [inline]
mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:580
hfs_extend_file+0xf9/0x1680 fs/hfs/extent.c:397
hfs_bmap_reserve+0x108/0x430 fs/hfs/btree.c:399
__hfs_ext_write_extent+0x1fc/0x470 fs/hfs/extent.c:121
hfs_ext_write_extent+0x17d/0x210 fs/hfs/extent.c:144
hfs_write_inode+0x117/0xa00 fs/hfs/inode.c:475
write_inode fs/fs-writeback.c:1623 [inline]
__writeback_single_inode+0x6a0/0x1230 fs/fs-writeback.c:1866
writeback_sb_inodes+0x9db/0x1ab0 fs/fs-writeback.c:2114
wb_writeback+0x41c/0xad0 fs/fs-writeback.c:2299
wb_do_writeback fs/fs-writeback.c:2467 [inline]
wb_workfn+0x437/0x10f0 fs/fs-writeback.c:2512
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
kthread+0x38b/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
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 ***
locks held by kworker/u8:36/7193: 3, last CPU#1:
#0: ffff88801e2f3938 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801e2f3938 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801e2f3938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#0: ffff88801e2f3938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#1: ffffc9000637fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc9000637fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc9000637fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#1: ffffc9000637fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#2: ffff88804009a0a0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x18d/0x300 fs/hfs/bfind.c:-1
stack backtrace:
CPU: 1 UID: 0 PID: 7193 Comm: kworker/u8:36 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Workqueue: writeback wb_workfn (flush-7:6)
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2087
check_noncircular+0x12f/0x150 kernel/locking/lockdep.c:2219
check_prev_add kernel/locking/lockdep.c:3209 [inline]
check_prevs_add kernel/locking/lockdep.c:3328 [inline]
validate_chain kernel/locking/lockdep.c:3952 [inline]
__lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288
lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
__mutex_lock_common kernel/locking/rtmutex_api.c:561 [inline]
mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:580
hfs_extend_file+0xf9/0x1680 fs/hfs/extent.c:397
hfs_bmap_reserve+0x108/0x430 fs/hfs/btree.c:399
__hfs_ext_write_extent+0x1fc/0x470 fs/hfs/extent.c:121
hfs_ext_write_extent+0x17d/0x210 fs/hfs/extent.c:144
hfs_write_inode+0x117/0xa00 fs/hfs/inode.c:475
write_inode fs/fs-writeback.c:1623 [inline]
__writeback_single_inode+0x6a0/0x1230 fs/fs-writeback.c:1866
writeback_sb_inodes+0x9db/0x1ab0 fs/fs-writeback.c:2114
wb_writeback+0x41c/0xad0 fs/fs-writeback.c:2299
wb_do_writeback fs/fs-writeback.c:2467 [inline]
wb_workfn+0x437/0x10f0 fs/fs-writeback.c:2512
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
kthread+0x38b/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
hfs: new node 0 already hashed?
------------[ cut here ]------------
1
WARNING: fs/hfs/bnode.c:478 at hfs_bnode_create+0x45a/0x4e0 fs/hfs/bnode.c:478, CPU#1: kworker/u8:36/7193
Modules linked in:
CPU: 1 UID: 0 PID: 7193 Comm: kworker/u8:36 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Workqueue: writeback wb_workfn (flush-7:6)
RIP: 0010:hfs_bnode_create+0x45a/0x4e0 fs/hfs/bnode.c:478
Code: 89 8b 89 ee e8 47 2a 77 fe e9 d6 fc ff ff e8 4d 9a 16 ff 4c 89 ef e8 65 41 ab 08 48 c7 c7 40 5f 89 8b 89 ee e8 27 2a 77 fe 90 <0f> 0b 90 eb b0 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c dd fb ff ff
RSP: 0018:ffffc9000637ed08 EFLAGS: 00010246
RAX: 000000000000001f RBX: ffff88804009a000 RCX: 490ff2c9f7094400
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000c6fd4d R12: 0000000000000000
R13: ffff88804009a0d0 R14: ffff88802a035800 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125cc2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffb92f9000 CR3: 000000003c2ee000 CR4: 00000000003526f0
Call Trace:
hfs_btree_inc_height+0xf9/0xac0 fs/hfs/brec.c:490
hfs_brec_insert+0x7eb/0xc80 fs/hfs/brec.c:148
__hfs_ext_write_extent+0x2a3/0x470 fs/hfs/extent.c:124
hfs_ext_write_extent+0x17d/0x210 fs/hfs/extent.c:144
hfs_write_inode+0x117/0xa00 fs/hfs/inode.c:475
write_inode fs/fs-writeback.c:1623 [inline]
__writeback_single_inode+0x6a0/0x1230 fs/fs-writeback.c:1866
writeback_sb_inodes+0x9db/0x1ab0 fs/fs-writeback.c:2114
wb_writeback+0x41c/0xad0 fs/fs-writeback.c:2299
wb_do_writeback fs/fs-writeback.c:2467 [inline]
wb_workfn+0x437/0x10f0 fs/fs-writeback.c:2512
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
kthread+0x38b/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245