INFO: task syz.4.2872:18351 blocked for more than 143 seconds. Not tainted 6.16.0-rc7-syzkaller-00142-gb711733e89a3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.2872 state:D stack:27240 pid:18351 tgid:18350 ppid:5841 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x116a/0x5dd0 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6879 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:747 fdget_pos+0x2a2/0x370 fs/file.c:1217 class_fd_pos_constructor include/linux/file.h:85 [inline] do_writev+0x75/0x340 fs/read_write.c:1094 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f37b178e9a9 RSP: 002b:00007f37b25fb038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007f37b19b5fa0 RCX: 00007f37b178e9a9 RDX: 0000000000000001 RSI: 0000200000000000 RDI: 0000000000000016 RBP: 00007f37b1810d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f37b19b5fa0 R15: 00007ffceb49f498 Showing all locks held in the system: 3 locks held by kworker/0:1/10: #0: ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline] #0: ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599 #1: ffff8880b8424088 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2c1/0x8e0 kernel/sched/psi.c:987 #2: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #2: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #2: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1155 [inline] #2: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x20a0 arch/x86/kernel/unwind_orc.c:479 1 lock held by khungtaskd/31: #0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770 5 locks held by kworker/u8:4/77: 6 locks held by kworker/1:2/92: #0: ffff888143a9b548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000259fd10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88802a120198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #2: ffff88802a120198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fe0 drivers/usb/core/hub.c:5898 #3: ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline] #3: ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599 #4: ffff8880b8524088 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2c1/0x8e0 kernel/sched/psi.c:987 #5: ffffffff9b027f40 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_deactivate+0x135/0x3a0 lib/debugobjects.c:873 2 locks held by getty/5593: #0: ffff888037ab20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 5 locks held by kworker/0:5/5902: #0: ffff888143a9b548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000450fd10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888144b6e198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #2: ffff888144b6e198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fe0 drivers/usb/core/hub.c:5898 #3: ffff888144f31510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3251 [inline] #3: ffff888144f31510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5463 [inline] #3: ffff888144f31510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #3: ffff888144f31510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline] #3: ffff888144f31510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2981/0x4fe0 drivers/usb/core/hub.c:5952 #4: ffff8881447b0868 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #4: ffff8881447b0868 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #4: ffff8881447b0868 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline] #4: ffff8881447b0868 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x29aa/0x4fe0 drivers/usb/core/hub.c:5952 1 lock held by syz.4.2872/18351: #0: ffff888034cd3278 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2a2/0x370 fs/file.c:1217 3 locks held by syz.4.2872/18352: #0: ffff888034cd3278 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2a2/0x370 fs/file.c:1217 #1: ffff88804bb36428 (sb_writers#20){.+.+}-{0:0}, at: do_writev+0x132/0x340 fs/read_write.c:1103 #2: ffff888056830148 (&sb->s_type->i_mutex_key#26){++++}-{4:4}, at: netfs_start_io_direct+0x116/0x260 fs/netfs/locking.c:188 1 lock held by syz.1.3473/20555: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc7-syzkaller-00142-gb711733e89a3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:470 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 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: 5816 Comm: syz-executor Not tainted 6.16.0-rc7-syzkaller-00142-gb711733e89a3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216 Code: e9 5d 4e 5a 00 be 03 00 00 00 5b e9 d2 09 1f 03 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 34 24 <65> 48 8b 15 78 17 14 12 65 8b 05 89 17 14 12 a9 00 01 ff 00 74 1d RSP: 0018:ffffc90003d6fcc0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff848d092e RDX: ffff888074bec880 RSI: ffffffff848d07c3 RDI: 0000000000000005 RBP: ffff8880752f7180 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000004 R12: 0000000000000004 R13: 0000000000000000 R14: ffff8880752f7180 R15: 00007ffd20b2ce4c FS: 000055558440c500(0000) GS:ffff888124720000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2c3f8ff8 CR3: 0000000029cdf000 CR4: 00000000003526f0 Call Trace: security_file_permission+0x83/0x210 security/security.c:2844 rw_verify_area+0xb9/0x680 fs/read_write.c:473 vfs_read+0x150/0xc60 fs/read_write.c:563 ksys_read+0x1f8/0x250 fs/read_write.c:715 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f59f3d8d37d Code: a8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb b5 e8 a8 48 00 00 0f 1f 84 00 00 00 00 00 80 3d c1 a1 1f 00 00 74 17 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 5b c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec RSP: 002b:00007ffd20b2ce38 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f59f3d8d37d RDX: 0000000000000004 RSI: 00007ffd20b2ce4c RDI: 0000000000000003 RBP: 0000000000000000 R08: 000000000002b8d0 R09: 00007f59f4c35000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd20b2d260 R13: 0000000000000004 R14: 00007ffd20b2ce4c R15: 00007ffd20b2cee0