INFO: task syz.7.784:12245 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.784 state:D stack:26688 pid:12245 tgid:12242 ppid:11686 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x14fb/0x52c0 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7285 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244 inode_lock_nested include/linux/fs.h:1073 [inline] __start_dirop fs/namei.c:2923 [inline] start_dirop fs/namei.c:2934 [inline] filename_rmdir+0x1cd/0x520 fs/namei.c:5386 __do_sys_rmdir fs/namei.c:5416 [inline] __se_sys_rmdir+0x2e/0x140 fs/namei.c:5413 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7feec42cc629 RSP: 002b:00007feec24fd028 EFLAGS: 00000246 ORIG_RAX: 0000000000000054 RAX: ffffffffffffffda RBX: 00007feec4546090 RCX: 00007feec42cc629 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000240 RBP: 00007feec4362b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007feec4546128 R14: 00007feec4546090 R15: 00007ffeaea718b8 Showing all locks held in the system: 2 locks held by rcuc/1/28: 1 lock held by khungtaskd/37: #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:7/183: #0: ffff88801aede138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88801aede138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc90003c47c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc90003c47c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 #2: ffff8880646260d0 (&type->s_umount_key#86){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565 #3: ffff88805f016368 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108 2 locks held by getty/5547: #0: ffff888030e820a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211 5 locks held by syz-executor/5778: 4 locks held by syz.7.784/12243: 2 locks held by syz.7.784/12245: #0: ffff888064626480 (sb_writers#32){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff88805f016738 (&type->i_mutex_dir_key#21/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff88805f016738 (&type->i_mutex_dir_key#21/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline] #1: ffff88805f016738 (&type->i_mutex_dir_key#21/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline] #1: ffff88805f016738 (&type->i_mutex_dir_key#21/1){+.+.}-{4:4}, at: filename_rmdir+0x1cd/0x520 fs/namei.c:5386 3 locks held by syz-executor/13638: 4 locks held by syz.2.988/14018: 2 locks held by syz.5.989/14021: 2 locks held by dhcpcd-run-hook/14043: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 14021 Comm: syz.5.989 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:arch_static_branch include/trace/events/preemptirq.h:40 [inline] RIP: 0010:trace_irq_enable+0x0/0x150 include/trace/events/preemptirq.h:40 Code: 00 00 65 c7 05 fd b0 82 10 00 00 00 00 c3 cc cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <41> 57 41 56 41 54 53 66 90 65 8b 05 a4 97 81 10 83 f8 08 73 37 89 RSP: 0000:ffffc900044d7a78 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000246 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8b2546b0 RBP: ffffc900044d7b60 R08: ffff8880693a8483 R09: 1ffff1100d275090 R10: dffffc0000000000 R11: ffffed100d275091 R12: 1ffff9200089af5d R13: 0000000000000246 R14: ffff8880693a8480 R15: ffffc900044d7ae0 FS: 00007fd08e9066c0(0000) GS:ffff888126443000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd086634000 CR3: 0000000031d60000 CR4: 00000000003526f0 Call Trace: trace_hardirqs_on+0x18/0x40 kernel/trace/trace_preemptirq.c:73 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline] _raw_spin_unlock_irqrestore+0x30/0x80 kernel/locking/spinlock.c:194 raw_spin_unlock_irqrestore_wake include/linux/sched/wake_q.h:97 [inline] rtlock_slowlock kernel/locking/rtmutex.c:1896 [inline] rtlock_lock kernel/locking/spinlock_rt.c:43 [inline] __rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline] rt_spin_lock+0x17a/0x400 kernel/locking/spinlock_rt.c:57 spin_lock include/linux/spinlock_rt.h:45 [inline] pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:402 do_anonymous_page mm/memory.c:5286 [inline] do_pte_missing+0x27f4/0x2d30 mm/memory.c:4475 handle_pte_fault mm/memory.c:6316 [inline] __handle_mm_fault mm/memory.c:6454 [inline] handle_mm_fault+0xd0a/0x13c0 mm/memory.c:6623 do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7fd090563b18 Code: 85 ed 74 3b 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 49 89 47 10 83 e9 01 73 d3 41 RSP: 002b:00007fd08e905470 EFLAGS: 00010282 RAX: 000000000014e000 RBX: 00007fd08e905530 RCX: 0000000000000016 RDX: 00000000000005ff RSI: 0000000000000200 RDI: 00007fd08e9055d0 RBP: 00000000000000e8 R08: 00007fd0864e6000 R09: 00000000000000fe R10: 0000200000012f42 R11: 0000000000009791 R12: 0000000000000181 R13: 00007fd090762200 R14: 0000000000000011 R15: 00007fd08e9055d0