INFO: task syz-executor.4:26364 blocked for more than 143 seconds. Not tainted 6.7.0-rc6-syzkaller-00022-g55cb5f43689d #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:28240 pid:26364 tgid:26358 ppid:5091 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0x1961/0x4ab0 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0x149/0x260 kernel/sched/core.c:6778 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6835 rwsem_down_write_slowpath+0xeea/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common+0x1aa/0x200 kernel/locking/rwsem.c:1306 inode_lock_nested include/linux/fs.h:837 [inline] do_rmdir+0x263/0x580 fs/namei.c:4236 __do_sys_unlinkat fs/namei.c:4424 [inline] __se_sys_unlinkat fs/namei.c:4418 [inline] __x64_sys_unlinkat+0xe0/0xf0 fs/namei.c:4418 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7fbeb4a7cbe9 RSP: 002b:00007fbeb58770c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 00007fbeb4b9c050 RCX: 00007fbeb4a7cbe9 RDX: 0000000000000200 RSI: 0000000020000000 RDI: 0000000000000007 RBP: 00007fbeb4ac847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007fbeb4b9c050 R15: 00007ffd7f18ad58 Showing all locks held in the system: 2 locks held by kworker/1:0/23: 1 lock held by khungtaskd/29: #0: ffffffff8d92dae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8d92dae0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8d92dae0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 5 locks held by kworker/u4:4/62: #0: ffff8880b983c358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 #1: ffff8880b9828808 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 #2: ffff8880b983c358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 #3: ffff8880b983c358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 #4: ffff8880b9828808 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_change+0xfd/0x280 kernel/sched/psi.c:912 2 locks held by getty/4814: #0: ffff88802654a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 2 locks held by syz-executor.5/5090: 3 locks held by syz-executor.4/26360: 2 locks held by syz-executor.4/26364: #0: ffff88803b81e418 (sb_writers#30){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:404 #1: ffff888077bd0930 (&sb->s_type->i_mutex_key#36/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:837 [inline] #1: ffff888077bd0930 (&sb->s_type->i_mutex_key#36/1){+.+.}-{3:3}, at: do_rmdir+0x263/0x580 fs/namei.c:4236 1 lock held by syz-executor.3/29155: #0: ffffffff8d9334b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #0: ffffffff8d9334b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x46c/0x890 kernel/rcu/tree_exp.h:996 1 lock held by syz-executor.2/29176: 2 locks held by syz-executor.4/29194: 1 lock held by udevadm/29225: 1 lock held by udevadm/29226: 3 locks held by syz-executor.0/29228: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.7.0-rc6-syzkaller-00022-g55cb5f43689d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x498/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x310 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfaf/0xff0 kernel/hung_task.c:379 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 29228 Comm: syz-executor.0 Not tainted 6.7.0-rc6-syzkaller-00022-g55cb5f43689d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 RIP: 0010:validate_chain+0x4/0x5ab0 kernel/locking/lockdep.c:3825 Code: d9 0f 8c 68 ff ff ff 48 c7 c7 80 f0 00 8f e8 93 ac 7c 00 48 89 d9 e9 54 ff ff ff e8 06 ad a9 09 66 0f 1f 44 00 00 f3 0f 1e fa <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec c0 02 RSP: 0000:ffffc90018817b88 EFLAGS: 00000086 RAX: 1ffffffff2155d94 RBX: ffffffff90aaeca0 RCX: 3eb26d79c4509b53 RDX: 0000000000000001 RSI: ffff8880272bc640 RDI: ffff8880272bbb80 RBP: 3eb26d79c4509b53 R08: ffffffff90dd7367 R09: 1ffffffff21bae6c R10: dffffc0000000000 R11: fffffbfff21bae6d R12: ffff8880272bbb80 R13: ffff8880272bbb80 R14: 0000000000000001 R15: ffff8880272bbb80 FS: 00007f32cd04a6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f32c34bc000 CR3: 00000000860be000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 rcu_lock_acquire include/linux/rcupdate.h:301 [inline] rcu_read_lock include/linux/rcupdate.h:747 [inline] lock_vma_under_rcu+0x1a8/0x6f0 mm/memory.c:5495 do_user_addr_fault arch/x86/mm/fault.c:1356 [inline] handle_page_fault arch/x86/mm/fault.c:1505 [inline] exc_page_fault+0x185/0x870 arch/x86/mm/fault.c:1561 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0033:0x7f32cc228806 Code: f0 72 6e 48 63 cd 48 01 c1 49 39 4f 08 72 4c 8d 4d ff 85 ed 74 33 66 0f 1f 44 00 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 <47> 0f b6 0c 08 45 84 c9 74 08 45 88 0c 00 49 8b 47 10 48 83 c0 01 RSP: 002b:00007f32cd049520 EFLAGS: 00010206 RAX: 0000000000abd001 RBX: 00007f32cd0495c0 RCX: 0000000000000076 RDX: 0000000000000001 RSI: 0000000000000001 RDI: 00007f32cd049660 RBP: 0000000000000102 R08: 00007f32c29ff000 R09: 0000000000abd000 R10: 0000000000000000 R11: 00007f32cd0495d0 R12: 0000000000000001 R13: 00007f32cc2ea620 R14: 0000000000000000 R15: 00007f32cd049660