INFO: task syz.4.2320:15162 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.2320 state:D stack:25608 pid:15162 tgid:15162 ppid:8880 task_flags:0x400040 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5254 [inline] __schedule+0x17c4/0x4d60 kernel/sched/core.c:6862 __schedule_loop kernel/sched/core.c:6944 [inline] schedule+0x165/0x360 kernel/sched/core.c:6959 request_wait_answer fs/fuse/dev.c:585 [inline] __fuse_request_send fs/fuse/dev.c:599 [inline] __fuse_simple_request+0x11cc/0x1bb0 fs/fuse/dev.c:693 fuse_simple_request fs/fuse/fuse_i.h:1250 [inline] fuse_flush+0x5d4/0x800 fs/fuse/file.c:482 filp_flush+0xbd/0x190 fs/open.c:1549 filp_close+0x1d/0x40 fs/open.c:1562 __range_close fs/file.c:767 [inline] __do_sys_close_range fs/file.c:826 [inline] __se_sys_close_range+0x359/0x650 fs/file.c:790 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1c68b8efc9 RSP: 002b:00007fff73f906f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 00007f1c68de7da0 RCX: 00007f1c68b8efc9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f1c68de7da0 R08: 0000000000000144 R09: 0000001273f909ef R10: 00007f1c68de7cb0 R11: 0000000000000246 R12: 00000000000b67a6 R13: 00007fff73f907f0 R14: ffffffffffffffff R15: 00007fff73f90810 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13d720 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13d720 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e13d720 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/1:1/43: #0: ffff8880b873a018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:638 #1: ffff8880b8724048 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 1 lock held by dhcpcd/5493: 1 lock held by dhcpcd/5626: 2 locks held by syz-executor/5811: 2 locks held by getty/7169: #0: ffff88803378d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9001b8332f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/9728: 1 lock held by syz-executor/12166: 1 lock held by syz-executor/15013: 1 lock held by syz.4.2320/15163: 1 lock held by syz.4.2320/15167: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:337 [inline] watchdog+0xfa9/0xff0 kernel/hung_task.c:500 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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: 5811 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:sigequalsets include/linux/signal.h:-1 [inline] RIP: 0010:__set_current_blocked+0x75/0x2c0 kernel/signal.c:3219 Code: 2b 00 74 08 4c 89 f7 e8 d9 8d 9e 00 4c 89 74 24 08 4d 8b 3e 4d 89 ee 49 c1 ee 03 41 80 3c 2e 00 74 08 4c 89 ef e8 bb 8d 9e 00 <4c> 89 2c 24 4d 8b 6d 00 4c 89 ff 4c 89 ee e8 38 91 38 00 4d 39 ef RSP: 0018:ffffc900040cfcd0 EFLAGS: 00000246 RAX: ffffffff8187e491 RBX: 1ffff110061b3c86 RCX: ffff888030d9dac0 RDX: 0000000000000000 RSI: 0000000000000010 RDI: ffffc900040cfd38 RBP: dffffc0000000000 R08: ffffffff8f9e8177 R09: 1ffffffff1f3d02e R10: dffffc0000000000 R11: fffffbfff1f3d02f R12: ffff888030d9dac0 R13: ffffc900040cfd38 R14: 1ffff92000819fa7 R15: 0000000000000000 FS: 000055556108c500(0000) GS:ffff888125def000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb5c38d64c0 CR3: 000000002175c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 000000000000000e DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: set_current_blocked kernel/signal.c:3208 [inline] signal_delivered kernel/signal.c:3070 [inline] signal_setup_done+0x188/0x310 kernel/signal.c:3082 handle_signal arch/x86/kernel/signal.c:312 [inline] arch_do_signal_or_restart+0x485/0x790 arch/x86/kernel/signal.c:339 exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1660a4d9c0 Code: 24 08 ff d0 48 83 c4 50 31 c0 5b 5d 41 5c 41 5d 41 5e c3 0f 1f 80 00 00 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 fb 44 8d 56 RSP: 002b:00007ffd88455178 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007ffd88455820 RCX: 00007f1660b8d99d RDX: 00007ffd88455180 RSI: 00007ffd884552b0 RDI: 0000000000000011 RBP: 0000000000000000 R08: 7fffffffffffffff R09: 3fffffffffffffff R10: 4000000000000000 R11: 0000000000000246 R12: 00007ffd88455b40 R13: 0000000000000004 R14: 00007ffd8845572c R15: 00007ffd884557c0