INFO: task syz-executor.0:6017 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:20600 pid:6017 tgid:6017 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5262 [inline] __schedule+0x1836/0x4ed0 kernel/sched/core.c:6870 __schedule_loop kernel/sched/core.c:6952 [inline] schedule+0x165/0x360 kernel/sched/core.c:6967 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7024 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 fuse_lock_inode+0xd3/0x120 fs/fuse/inode.c:604 fuse_lookup+0x18a/0x640 fs/fuse/dir.c:427 __lookup_slow+0x297/0x3d0 fs/namei.c:1855 lookup_slow+0x53/0x70 fs/namei.c:1872 walk_component fs/namei.c:2190 [inline] link_path_walk+0xb4e/0x11f0 fs/namei.c:2558 path_openat+0x2bb/0x3860 fs/namei.c:4169 do_filp_open+0x1fa/0x410 fs/namei.c:4200 do_sys_openat2+0x121/0x1c0 fs/open.c:1434 do_sys_open fs/open.c:1449 [inline] __do_sys_openat fs/open.c:1465 [inline] __se_sys_openat fs/open.c:1460 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1460 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: 0033:0x7f1abde7c391 RSP: 002b:00007ffc5294e570 EFLAGS: 00000287 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f1abde7c391 RDX: 0000000000090800 RSI: 00007f1abded7b96 RDI: 00000000ffffff9c RBP: 00007ffc5294e63c R08: 0000000000000000 R09: 3fffffffffffffff R10: 0000000000000000 R11: 0000000000000287 R12: 0000000000000000 R13: 000000000001787f R14: 000000000001785a R15: 0000000000000008 INFO: task syz-executor.0:6077 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:24408 pid:6077 tgid:6073 ppid:6017 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5262 [inline] __schedule+0x1836/0x4ed0 kernel/sched/core.c:6870 __schedule_loop kernel/sched/core.c:6952 [inline] schedule+0x165/0x360 kernel/sched/core.c:6967 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:1242 [inline] fuse_lookup_name+0x34c/0x860 fs/fuse/dir.c:381 fuse_lookup+0x1e9/0x640 fs/fuse/dir.c:428 __lookup_slow+0x297/0x3d0 fs/namei.c:1855 lookup_slow+0x53/0x70 fs/namei.c:1872 walk_component fs/namei.c:2190 [inline] link_path_walk+0xb4e/0x11f0 fs/namei.c:2558 path_openat+0x2bb/0x3860 fs/namei.c:4169 do_filp_open+0x1fa/0x410 fs/namei.c:4200 do_sys_openat2+0x121/0x1c0 fs/open.c:1434 do_sys_open fs/open.c:1449 [inline] __do_sys_openat fs/open.c:1465 [inline] __se_sys_openat fs/open.c:1460 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1460 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: 0033:0x7f1abde7b5e0 RSP: 002b:00007f1abec46e20 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f1abde7b5e0 RDX: 0000000000000002 RSI: 00007f1abec46f40 RDI: 00000000ffffff9c RBP: 00007f1abec46f40 R08: 0000000000000000 R09: 00000000000010f7 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000005 R13: 00007f1abec46f3c R14: 00007f1abec46f40 R15: 00007f1ab4c00000 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3d560 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d560 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3d560 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5584: #0: ffff888032f200a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036c32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by syz-executor.0/6017: #0: ffff8880779b0148 (&type->i_mutex_dir_key#8){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1066 [inline] #0: ffff8880779b0148 (&type->i_mutex_dir_key#8){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1871 #1: ffff8880779b05f8 (&fi->mutex){+.+.}-{4:4}, at: fuse_lock_inode+0xd3/0x120 fs/fuse/inode.c:604 2 locks held by syz-executor.0/6077: #0: ffff8880779b0148 (&type->i_mutex_dir_key#8){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1066 [inline] #0: ffff8880779b0148 (&type->i_mutex_dir_key#8){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1871 #1: ffff8880779b05f8 (&fi->mutex){+.+.}-{4:4}, at: fuse_lock_inode+0xd3/0x120 fs/fuse/inode.c:604 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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:336 [inline] watchdog+0xfa8/0xff0 kernel/hung_task.c:499 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 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: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:kasan_check_range+0x1d4/0x2c0 mm/kasan/generic.c:200 Code: 01 f3 49 8d 5c 24 07 4d 85 e4 49 0f 49 dc 48 83 e3 f8 49 29 dc 74 12 41 80 3b 00 0f 85 b8 00 00 00 49 ff c3 49 ff cc 75 ee 5b <41> 5c 41 5d 41 5e 41 5f 5d e9 0e 37 35 09 cc 45 84 ff 75 63 41 f7 RSP: 0018:ffffffff8dc07b10 EFLAGS: 00000256 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8b5b5eda RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8f7dd070 RBP: ffffffff8dc07d70 R08: ffffffff8f7dd077 R09: 1ffffffff1efba0e R10: dffffc0000000000 R11: fffffbfff1efba0f R12: 0000000000000001 R13: 0000000000000000 R14: fffffbfff1efba0f R15: 1ffffffff1efba0e FS: 0000000000000000(0000) GS:ffff888125ec1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055d6328fa660 CR3: 000000000dd38000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:646 [inline] cpu_online include/linux/cpumask.h:1205 [inline] trace_sched_entry_tp include/trace/events/sched.h:882 [inline] __schedule+0xea/0x4ed0 kernel/sched/core.c:6741 schedule_idle+0x52/0x90 kernel/sched/core.c:6993 do_idle+0x4a7/0x510 kernel/sched/idle.c:358 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 rest_init+0x2de/0x300 init/main.c:757 start_kernel+0x3a7/0x410 init/main.c:1206 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147