INFO: task syz.4.712:12618 blocked for more than 143 seconds. Not tainted 6.12.0-syzkaller-10313-g7d4050728c83 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.712 state:D stack:25952 pid:12618 tgid:12597 ppid:10755 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694 inode_lock_nested include/linux/fs.h:853 [inline] filename_create+0x260/0x540 fs/namei.c:4080 do_mkdirat+0xbd/0x3a0 fs/namei.c:4326 __do_sys_mkdirat fs/namei.c:4349 [inline] __se_sys_mkdirat fs/namei.c:4347 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4347 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f429997f077 RSP: 002b:00007f429a7b9e88 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f429a7b9f10 RCX: 00007f429997f077 RDX: 00000000000001ff RSI: 0000000020000140 RDI: 00000000ffffff9c RBP: 0000000020000180 R08: 0000000020000000 R09: 0000000000000000 R10: 0000000020000180 R11: 0000000000000246 R12: 0000000020000140 R13: 00007f429a7b9ed0 R14: 0000000000000000 R15: 0000000020000600 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e93c560 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e93c560 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e93c560 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 2 locks held by kworker/u8:2/35: 2 locks held by getty/5598: #0: ffff8880313270a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz.4.712/12606: 2 locks held by syz.4.712/12618: #0: ffff888069c00420 (sb_writers#43){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff88807ba40180 (&type->i_mutex_dir_key#27/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:853 [inline] #1: ffff88807ba40180 (&type->i_mutex_dir_key#27/1){+.+.}-{4:4}, at: filename_create+0x260/0x540 fs/namei.c:4080 2 locks held by syz-executor/12744: #0: ffff888079d120e0 (&type->s_umount_key#31){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888079d120e0 (&type->s_umount_key#31){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888079d120e0 (&type->s_umount_key#31){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8ea004e8 (lock#3){+.+.}-{4:4}, at: __lru_add_drain_all+0x66/0x560 mm/swap.c:798 2 locks held by syz-executor/13147: #0: ffff888052ef00e0 (&type->s_umount_key#66){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888052ef00e0 (&type->s_umount_key#66){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888052ef00e0 (&type->s_umount_key#66){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8ea004e8 (lock#3){+.+.}-{4:4}, at: __lru_add_drain_all+0x66/0x560 mm/swap.c:798 2 locks held by syz.7.898/14252: #0: ffffffff8eecf3a8 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_super fs/btrfs/super.c:1841 [inline] #0: ffffffff8eecf3a8 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree+0x2f4/0x1a10 fs/btrfs/super.c:2105 #1: ffffffff8ea004e8 (lock#3){+.+.}-{4:4}, at: __lru_add_drain_all+0x66/0x560 mm/swap.c:798 1 lock held by syz.1.901/14269: #0: ffffffff8eecf3a8 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_super fs/btrfs/super.c:1841 [inline] #0: ffffffff8eecf3a8 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree+0x2f4/0x1a10 fs/btrfs/super.c:2105 2 locks held by rm/14283: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-syzkaller-10313-g7d4050728c83 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xffb/0x1040 kernel/hung_task.c:397 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 12606 Comm: syz.4.712 Not tainted 6.12.0-syzkaller-10313-g7d4050728c83 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:validate_chain+0x5ce/0x5920 kernel/locking/lockdep.c:3916 Code: 00 00 0f 84 2e 3f 00 00 b8 01 00 00 00 48 c7 84 24 00 01 00 00 0e 36 e0 45 49 c7 04 0c 00 00 00 00 49 c7 44 0c 09 00 00 00 00 <49> c7 44 0c 11 00 00 00 00 49 c7 44 0c 1f 00 00 00 00 49 c7 44 0c RSP: 0018:ffffc90005186ac0 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000020021 RCX: 1ffff92000a30d78 RDX: 0000000000000000 RSI: ffff88802ef0e558 RDI: ffff88802ef0da00 RBP: ffffc90005186dc0 R08: ffffffff942ef887 R09: 1ffffffff285df10 R10: dffffc0000000000 R11: fffffbfff285df11 R12: dffffc0000000000 R13: ffff88802ef0e578 R14: 0e9172f369dcab0b R15: 0000000000000000 FS: 00007f429a7db6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0273350000 CR3: 0000000056a06000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ref_add_unless include/linux/page_ref.h:235 [inline] folio_ref_add_unless include/linux/page_ref.h:248 [inline] folio_try_get+0x3b/0x350 include/linux/page_ref.h:264 filemap_get_entry+0x240/0x3b0 mm/filemap.c:1851 __filemap_get_folio+0x71/0xbd0 mm/filemap.c:1886 grow_dev_folio fs/buffer.c:1039 [inline] grow_buffers fs/buffer.c:1105 [inline] __getblk_slow fs/buffer.c:1131 [inline] bdev_getblk+0x1d8/0x550 fs/buffer.c:1431 __bread_gfp+0x86/0x400 fs/buffer.c:1485 sb_bread include/linux/buffer_head.h:346 [inline] get_branch+0x2c3/0x6e0 fs/sysv/itree.c:102 get_block+0x180/0x16d0 fs/sysv/itree.c:222 block_read_full_folio+0x418/0xcd0 fs/buffer.c:2396 filemap_read_folio+0x14b/0x630 mm/filemap.c:2366 do_read_cache_folio+0x3f5/0x850 mm/filemap.c:3826 read_mapping_folio include/linux/pagemap.h:1011 [inline] dir_get_folio fs/sysv/dir.c:64 [inline] sysv_find_entry+0x16a/0x4b0 fs/sysv/dir.c:154 sysv_inode_by_name+0x98/0x2a0 fs/sysv/dir.c:370 sysv_lookup+0x6b/0xe0 fs/sysv/namei.c:38 lookup_open fs/namei.c:3627 [inline] open_last_lookups fs/namei.c:3748 [inline] path_openat+0x11a7/0x3590 fs/namei.c:3984 do_filp_open+0x27f/0x4e0 fs/namei.c:4014 do_sys_openat2+0x13e/0x1d0 fs/open.c:1402 do_sys_open fs/open.c:1417 [inline] __do_sys_openat fs/open.c:1433 [inline] __se_sys_openat fs/open.c:1428 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1428 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4299980809 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f429a7db058 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f4299b46160 RCX: 00007f4299980809 RDX: 000000000000275a RSI: 0000000020000040 RDI: ffffffffffffff9c RBP: 00007f42999f393e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f4299b46160 R15: 00007ffeaf4a4148