INFO: task syz.1.1949:22214 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1949 state:D stack:28592 pid:22214 tgid:22180 ppid:21545 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6908 __schedule_loop kernel/sched/core.c:6990 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7286 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 include/linux/fs.h:1028 [inline] open_last_lookups fs/namei.c:4580 [inline] path_openat+0xb5e/0x38a0 fs/namei.c:4827 do_file_open+0x23e/0x4a0 fs/namei.c:4859 do_sys_openat2+0x113/0x200 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1383 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: 0033:0x7f7e6b7ec799 RSP: 002b:00007f7e69a25028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f7e6ba66090 RCX: 00007f7e6b7ec799 RDX: 000000000000275a RSI: 00002000000004c0 RDI: ffffffffffffff9c RBP: 00007f7e6b882c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7e6ba66128 R14: 00007f7e6ba66090 R15: 00007ffe3ff47698 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8ddcb880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcb880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcb880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5566: #0: ffff888037c470a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211 4 locks held by kworker/u8:3/16617: #0: ffff88801aee5138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88801aee5138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc9000640fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc9000640fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 #2: ffff88803ef5c0d0 (&type->s_umount_key#64){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565 #3: ffff88805cc40ba8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108 4 locks held by syz.1.1949/22182: 2 locks held by syz.1.1949/22214: #0: ffff88803ef5c480 (sb_writers#17){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff88805cc40f78 (&type->i_mutex_dir_key#13){++++}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline] #1: ffff88805cc40f78 (&type->i_mutex_dir_key#13){++++}-{4:4}, at: open_last_lookups fs/namei.c:4580 [inline] #1: ffff88805cc40f78 (&type->i_mutex_dir_key#13){++++}-{4:4}, at: path_openat+0xb5e/0x38a0 fs/namei.c:4827 3 locks held by syz.2.2206/24429: 3 locks held by syz.3.2207/24438: 4 locks held by syz.0.2208/24441: 1 lock held by dhcpcd-run-hook/24443: #0: ffff888038f7f0d8 (&pipe->rd_wait){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #0: ffff888038f7f0d8 (&pipe->rd_wait){+.+.}-{3:3}, at: finish_wait+0xbe/0x1e0 kernel/sched/wait.c:394 2 locks held by sed/24458: 1 lock held by syz.4.2211/24468: #0: ffff88805be3c0d0 (&type->s_umount_key#29/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345 1 lock held by udevadm/24464: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026 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:436 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5162 Comm: klogd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026 RIP: 0010:vsnprintf+0xa9e/0xee0 lib/vsprintf.c:2887 Code: c3 0b f7 eb bf e8 02 b5 a5 f6 49 ff c7 4d 89 fd eb 0d e8 f5 b4 a5 f6 4d 89 fd 4c 8b 74 24 08 48 89 e8 48 c1 e8 03 0f b6 04 18 <84> c0 75 53 80 7d 00 00 0f 84 0e 03 00 00 e8 cf b4 a5 f6 49 89 ef RSP: 0018:ffffc90003b2f7f0 EFLAGS: 00000a02 RAX: 0000000000000005 RBX: dffffc0000000000 RCX: ffff888038d89e80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff8b4da263 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc90003b2f740 R11: fffff52000765eeb R12: ffffc90003b2f8e0 R13: ffffc90003b2fac2 R14: 0000000000000401 R15: 0000000000000006 FS: 00007fcbac74dc80(0000) GS:ffff88812633c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6cbbba7000 CR3: 0000000039116000 CR4: 00000000003526f0 Call Trace: sprintf+0xe7/0x140 lib/vsprintf.c:3111 print_syslog kernel/printk/printk.c:1352 [inline] info_print_prefix+0xdc/0x360 kernel/printk/printk.c:1382 record_print_text+0x176/0x450 kernel/printk/printk.c:1434 syslog_print+0x3b0/0x610 kernel/printk/printk.c:1645 do_syslog+0x583/0x7d0 kernel/printk/printk.c:1763 __do_sys_syslog kernel/printk/printk.c:1855 [inline] __se_sys_syslog kernel/printk/printk.c:1853 [inline] __x64_sys_syslog+0x7c/0x90 kernel/printk/printk.c:1853 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: 0033:0x7fcbac917a37 Code: 73 01 c3 48 8b 0d c1 f3 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 91 f3 0c 00 f7 d8 64 89 01 48 RSP: 002b:00007fff63b86e68 EFLAGS: 00000206 ORIG_RAX: 0000000000000067 RAX: ffffffffffffffda RBX: 00007fcbacab7490 RCX: 00007fcbac917a37 RDX: 00000000000003ff RSI: 00007fcbacab7490 RDI: 0000000000000002 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000206 R12: 00007fcbacab7490 R13: 00007fcbaca94dfe R14: 00007fcbacab7877 R15: 00007fcbacab7877