rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2629 jiffies s: 118877 root: 0x1/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 26194 Comm: syz-executor Not tainted 6.10.0-next-20240724-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:io_serial_in+0x76/0xb0 drivers/tty/serial/8250/8250_port.c:406 Code: e0 cb 52 fc 89 e9 41 d3 e6 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 11 52 ba fc 44 03 33 44 89 f2 ec <0f> b6 c0 5b 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c RSP: 0018:ffffc90000007378 EFLAGS: 00000002 RAX: 1ffffffff2966300 RBX: ffffffff94b31e00 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020 RBP: 0000000000000000 R08: ffffffff8540ff36 R09: 1ffff11003f3c046 R10: dffffc0000000000 R11: ffffffff8540fef0 R12: dffffc0000000000 R13: ffffffff94843f10 R14: 00000000000003fd R15: dffffc0000000000 FS: 00005555772bd500(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe514ffbf8 CR3: 000000004679c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_in drivers/tty/serial/8250/8250.h:137 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline] wait_for_lsr drivers/tty/serial/8250/8250_port.c:2068 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3315 [inline] serial8250_console_write+0x1373/0x1ed0 drivers/tty/serial/8250/8250_port.c:3393 console_emit_next_record kernel/printk/printk.c:3030 [inline] console_flush_all+0x880/0xf50 kernel/printk/printk.c:3102 console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3173 vprintk_emit+0x7a1/0x900 kernel/printk/printk.c:2423 _printk+0xd5/0x120 kernel/printk/printk.c:2450 sched_show_task+0x4d7/0x6d0 kernel/sched/core.c:7505 report_rtnl_holders+0x327/0x400 net/core/rtnetlink.c:110 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2417 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428 run_timer_base kernel/time/timer.c:2437 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5826 Code: 2b 00 74 08 4c 89 f7 e8 6a a0 8b 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90004997600 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000932ecc RCX: e02f843a3cb4f600 RDX: dffffc0000000000 RSI: ffffffff8bcae6c0 RDI: ffffffff8c2078c0 RBP: ffffc90004997748 R08: ffffffff9300b807 R09: 1ffffffff2601700 R10: dffffc0000000000 R11: fffffbfff2601701 R12: 1ffff92000932ec8 R13: dffffc0000000000 R14: ffffc90004997660 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:326 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] __pte_offset_map+0x9e/0x380 mm/pgtable-generic.c:287 __pte_offset_map_lock+0xc7/0x300 mm/pgtable-generic.c:371 pte_offset_map_lock include/linux/mm.h:2985 [inline] __get_locked_pte mm/memory.c:1989 [inline] get_locked_pte include/linux/mm.h:2709 [inline] insert_page mm/memory.c:2073 [inline] vm_insert_page+0x4a9/0x710 mm/memory.c:2226 kcov_mmap+0xda/0x140 kernel/kcov.c:496 call_mmap include/linux/fs.h:2129 [inline] mmap_region+0xe8f/0x2090 mm/mmap.c:2957 do_mmap+0x8f9/0x1010 mm/mmap.c:1468 vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:588 ksys_mmap_pgoff+0x4f1/0x720 mm/mmap.c:1514 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe91cf75f53 Code: f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 41 89 ca 41 f7 c1 ff 0f 00 00 75 14 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 25 c3 0f 1f 40 00 48 c7 c0 a8 ff ff ff 64 c7 RSP: 002b:00007ffe10a4d2b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fe91d105f20 RCX: 00007fe91cf75f53 RDX: 0000000000000003 RSI: 0000000000800000 RDI: 00007fe91b401000 RBP: 00007fe91b400000 R08: 00000000000000d7 R09: 0000000000000000 R10: 0000000000000011 R11: 0000000000000246 R12: 000000000000000c R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000009 Workqueue: 0x0 (events_power_efficient) Call Trace: context_switch kernel/sched/core.c:5239 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6603 __schedule_loop kernel/sched/core.c:6680 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6695 worker_thread+0xa2c/0xd40 kernel/workqueue.c:3405 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 2 locks held by getty/4861: #0: ffff88802a8950a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2211 5 locks held by kworker/u8:1/23230: #0: ffff888015edd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015edd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90003eefd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90003eefd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8f5fad50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594 #3: ffff88801e05d428 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_destruct+0x110/0x2e0 drivers/net/wireguard/device.c:249 #4: ffffffff8e33ce38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #4: ffffffff8e33ce38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:967 5 locks held by kworker/u9:2/23523: #0: ffff888060cfe148 ((wq_completion)hci5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888060cfe148 ((wq_completion)hci5){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc9000368fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc9000368fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffff88805adc8d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_cmd_sync_work+0x1ec/0x400 net/bluetooth/hci_sync.c:327 #3: ffff88805adc8078 (&hdev->lock){+.+.}-{3:3}, at: hci_abort_conn_sync+0x1ea/0xde0 net/bluetooth/hci_sync.c:5512 #4: ffffffff8f7733e8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1962 [inline] #4: ffffffff8f7733e8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_failed+0x185/0x340 net/bluetooth/hci_conn.c:1265 1 lock held by syz-executor/26035: #0: ffffffff8e33ce38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e33ce38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:967 4 locks held by syz.0.5515/26174: #0: ffffffff8eb3d068 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 #1: ffffffff8e1eab48 (system_transition_mutex){+.+.}-{3:3}, at: lock_system_sleep+0x60/0xa0 kernel/power/main.c:56 #2: ffffffff8e20aff0 ((pm_chain_head).rwsem){++++}-{3:3}, at: blocking_notifier_call_chain_robust+0xac/0x1e0 kernel/notifier.c:352 #3: ffffffff8e33cd00 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:4486 1 lock held by syz.3.5520/26180: #0: ffffffff8eb3d068 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 1 lock held by syz.3.5520/26182: #0: ffffffff8eb3d068 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 1 lock held by syz.4.5521/26187: #0: ffffffff8eb3d068 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 1 lock held by syz.4.5521/26188: #0: ffffffff8eb3d068 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 4 locks held by syz-executor/26194: #0: ffff88802e571e18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:122 [inline] #0: ffff88802e571e18 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x17c/0x3d0 mm/util.c:586 #1: ffffffff8e337a60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #1: ffffffff8e337a60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #1: ffffffff8e337a60 (rcu_read_lock){....}-{1:2}, at: __pte_offset_map+0x82/0x380 mm/pgtable-generic.c:287 #2: ffffc90000007c00 (net/core/rtnetlink.c:83){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x650 kernel/time/timer.c:1789 #3: ffffffff8e337a60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #3: ffffffff8e337a60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #3: ffffffff8e337a60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6695 1 lock held by syz-executor/26197: #0: ffffffff8eb3d068 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 1 lock held by syz-executor/26198: #0: ffffffff8eb3d068 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 1 lock held by syz-executor/26200: #0: ffffffff8eb3d068 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 1 lock held by syz-executor/26202: #0: ffffffff8eb3d068 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 1 lock held by syz-executor/26203: #0: ffffffff8eb3d068 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 =============================================