INFO: task syz.2.2263:14675 blocked for more than 143 seconds. Tainted: G L syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.2263 state:D stack:24624 pid:14675 tgid:14675 ppid:5635 task_flags:0x40004c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5583 [inline] __schedule+0x17dd/0x5820 kernel/sched/core.c:7382 __schedule_loop kernel/sched/core.c:7459 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7474 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531 rwsem_down_read_slowpath+0x6d8/0x980 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x97/0x320 kernel/locking/rwsem.c:1576 mmap_read_lock include/linux/mmap_lock.h:600 [inline] exit_mm+0x77/0x240 kernel/exit.c:562 do_exit+0x6a8/0x2360 kernel/exit.c:967 do_group_exit+0x22d/0x2f0 kernel/exit.c:1123 __do_sys_exit_group kernel/exit.c:1134 [inline] __se_sys_exit_group kernel/exit.c:1132 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1132 x64_sys_call+0x18c6/0x18d0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4cdd99f559 RSP: 002b:00007f4cddd4fd88 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4cdd99f559 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f4cddd4fdec R08: 0000000000000000 R09: 0000555577343a00 R10: 0000000000000006 R11: 0000000000000246 R12: 00000000000001b9 R13: 0000555577343a00 R14: 00000000000b5a98 R15: 00007f4cddd4fe40 INFO: task syz.2.2263:14677 blocked for more than 143 seconds. Tainted: G L syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.2263 state:D stack:25992 pid:14677 tgid:14675 ppid:5635 task_flags:0x40054c flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5583 [inline] __schedule+0x17dd/0x5820 kernel/sched/core.c:7382 __schedule_loop kernel/sched/core.c:7459 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7474 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531 rwsem_down_read_slowpath+0x6d8/0x980 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x97/0x320 kernel/locking/rwsem.c:1576 mmap_read_lock include/linux/mmap_lock.h:600 [inline] exit_mm+0x77/0x240 kernel/exit.c:562 do_exit+0x6a8/0x2360 kernel/exit.c:967 do_group_exit+0x22d/0x2f0 kernel/exit.c:1123 get_signal+0x1216/0x12c0 kernel/signal.c:3112 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline] do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4cdd99f559 RSP: 002b:00007f4cde8ec028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: 0000000000119f80 RBX: 00007f4cddc25fa0 RCX: 00007f4cdd99f559 RDX: 000000000208e24b RSI: 0000200000000080 RDI: 0000000000000006 RBP: 00007f4cdda36b20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4cddc26038 R14: 00007f4cddc25fa0 R15: 00007f4cddd4fa48 INFO: task syz.2.2263:14678 blocked for more than 143 seconds. Tainted: G L syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.2263 state:D stack:27472 pid:14678 tgid:14675 ppid:5635 task_flags:0x40054c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5583 [inline] __schedule+0x17dd/0x5820 kernel/sched/core.c:7382 __schedule_loop kernel/sched/core.c:7459 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7474 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531 rwsem_down_read_slowpath+0x6d8/0x980 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x97/0x320 kernel/locking/rwsem.c:1576 mmap_read_lock include/linux/mmap_lock.h:600 [inline] exit_mm+0x77/0x240 kernel/exit.c:562 do_exit+0x6a8/0x2360 kernel/exit.c:967 do_group_exit+0x22d/0x2f0 kernel/exit.c:1123 get_signal+0x1216/0x12c0 kernel/signal.c:3112 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline] do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4cdd99f559 RSP: 002b:00007f4cde8cb0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f4cddc26098 RCX: 00007f4cdd99f559 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f4cddc26098 RBP: 00007f4cddc26090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4cddc26128 R14: 00007f4cddd4f960 R15: 00007f4cddd4fa48 INFO: task syz.2.2263:14683 blocked for more than 143 seconds. Tainted: G L syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.2263 state:D stack:28808 pid:14683 tgid:14675 ppid:5635 task_flags:0x40044c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5583 [inline] __schedule+0x17dd/0x5820 kernel/sched/core.c:7382 __schedule_loop kernel/sched/core.c:7459 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7474 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531 rwsem_down_read_slowpath+0x6d8/0x980 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x97/0x320 kernel/locking/rwsem.c:1576 mmap_read_lock include/linux/mmap_lock.h:600 [inline] exit_mm+0x77/0x240 kernel/exit.c:562 do_exit+0x6a8/0x2360 kernel/exit.c:967 do_group_exit+0x22d/0x2f0 kernel/exit.c:1123 get_signal+0x1216/0x12c0 kernel/signal.c:3112 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline] do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4cdd99f559 RSP: 002b:00007f4cde8890e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f4cddc26278 RCX: 00007f4cdd99f559 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f4cddc26278 RBP: 00007f4cddc26270 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4cddc26308 R14: 00007f4cddd4f960 R15: 00007f4cddd4fa48 Showing all locks held in the system: locks held by pr/ttyS0/32: 2, last CPU#1: #0: ffffffff8fc33858 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline] #0: ffffffff8fc33858 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:493 [inline] #0: ffffffff8fc33858 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x30/0x60 kernel/printk/printk.c:291 #1: ffffffff9bdbaab8 (&port_lock_key){-.-.}-{3:3}, at: __uart_port_lock_irqsave include/linux/serial_core.h:613 [inline] #1: ffffffff9bdbaab8 (&port_lock_key){-.-.}-{3:3}, at: univ8250_console_device_lock+0x67/0xc0 drivers/tty/serial/8250/8250_core.c:413 locks held by khungtaskd/33: 1, last CPU#0: #0: ffffffff8fd59ca0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8fd59ca0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8fd59ca0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871 locks held by getty/5382: 2, on CPU#1: #0: ffff8880375df0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032432e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 locks held by kworker/u8:26/7386: 3, last CPU#0: #0: ffff88801c0ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88801c0ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88801c0ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline] #0: ffff88801c0ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578 #1: ffffc90007057c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90007057c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90007057c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline] #1: ffffc90007057c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578 #2: ffff888049c1d258 (&devlink->lock_key#9){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb30 drivers/net/netdevsim/dev.c:834 locks held by kworker/1:11/8637: 6, last CPU#1: #0: ffff88801fabe948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88801fabe948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88801fabe948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline] #0: ffff88801fabe948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578 #1: ffffc90006b4fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] ffffc90006b4fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] ffffc90006b4fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline] ffffc90006b4fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578 #2: ffff88802aee21d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline] #2: ffff88802aee21d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4d30 drivers/usb/core/hub.c:5917 #3: ffff88804495d1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline] #3: ffff88804495d1d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1073 #4: ffff88804319f1a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline] #4: ffff88804319f1a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1073 #5: ffffffff911e6920 (register_mutex#6){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #5: ffffffff911e6920 (register_mutex#6){+.+.}-{4:4}, at: usb_audio_probe+0x5e6/0x2240 sound/usb/card.c:985 locks held by udevd/11821: 4, on CPU#0: #0: ffff888021ea1638 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xa4/0xca0 fs/seq_file.c:183 #1: ffff888028a77480 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5d/0x420 fs/kernfs/file.c:165 #2: ffff888057de5a58 (kn->active#30){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888057de5a58 (kn->active#30){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:166 #3: ffff88804495d1d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1109 [inline] #3: ffff88804495d1d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 locks held by syz.2.2263/14675: 1, on CPU#1: #0: ffff88807ecc2800 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline] #0: ffff88807ecc2800 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0x77/0x240 kernel/exit.c:562 locks held by syz.2.2263/14677: 1, on CPU#1: #0: ffff88807ecc2800 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline] #0: ffff88807ecc2800 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0x77/0x240 kernel/exit.c:562 locks held by syz.2.2263/14678: 1, on CPU#0: #0: ffff88807ecc2800 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline] #0: ffff88807ecc2800 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0x77/0x240 kernel/exit.c:562 locks held by syz.2.2263/14681: 3, last CPU#0: #0: ffff88807ecc2800 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline] #0: ffff88807ecc2800 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1dd/0x4e0 mm/util.c:579 #1: ffff88807f6f51a0 (reservation_ww_class_mutex){+.+.}-{4:4}, at: dma_resv_lock include/linux/dma-resv.h:345 [inline] #1: ffff88807f6f51a0 (reservation_ww_class_mutex){+.+.}-{4:4}, at: drm_gem_shmem_mmap+0x1df/0x490 drivers/gpu/drm/drm_gem_shmem_helper.c:777 #2: ffffffff8fd59ca0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #2: ffffffff8fd59ca0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #2: ffffffff8fd59ca0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline] #2: ffffffff8fd59ca0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495 locks held by syz.2.2263/14683: 1, on CPU#0: #0: ffff88807ecc2800 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline] #0: ffff88807ecc2800 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0x77/0x240 kernel/exit.c:562 locks held by kworker/0:7/15256: 6, on CPU#0: #0: ffff88801fabe948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88801fabe948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88801fabe948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline] #0: ffff88801fabe948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578 #1: ffffc90004e37c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90004e37c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90004e37c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline] #1: ffffc90004e37c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578 #2: ffff88802a28b1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline] #2: ffff88802a28b1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4d30 drivers/usb/core/hub.c:5917 #3: ffff88802a28e568 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3270 [inline] #3: ffff88802a28e568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5482 [inline] #3: ffff88802a28e568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5725 [inline] #3: ffff88802a28e568 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5889 [inline] #3: ffff88802a28e568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x20a1/0x4d30 drivers/usb/core/hub.c:5971 #4: ffff88802af0c660 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5483 [inline] #4: ffff88802af0c660 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5725 [inline] #4: ffff88802af0c660 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5889 [inline] #4: ffff88802af0c660 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x20c9/0x4d30 drivers/usb/core/hub.c:5971 #5: ffffffff90b03cc8 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x14d/0x1810 drivers/usb/core/hub.c:3085 locks held by syz.6.2717/16811: 2, last CPU#0: #0: ffff888030e94cc0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline] #0: ffff888030e94cc0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x1a4/0x9f0 mm/mmap.c:1299 #1: ffffffff8fd59ca0 (rcu_read_lock){....}-{1:3}, at: raw_spin_rq_lock_nested+0xb2/0x160 kernel/sched/core.c:685 locks held by syz.7.2689/16809: 2, last CPU#0: #0: ffff88802b7d4080 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline] #0: ffff88802b7d4080 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x1a4/0x9f0 mm/mmap.c:1299 #1: ffffffff8fd59ca0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffffff8fd59ca0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff8fd59ca0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290 locks held by syz.1.2725/16817: 1, last CPU#0: #0: ffff88802b7d3440 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:544 [inline] #0: ffff88802b7d3440 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x2d8/0x9f0 mm/mmap.c:1323 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 33 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123 nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66 trigger_all_cpu_backtrace include/linux/nmi.h:164 [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:353 [inline] watchdog+0xfd2/0x1030 kernel/hung_task.c:561 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: 32 Comm: pr/ttyS0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409 Code: e8 2e 54 50 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 bf 4b c1 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07 RSP: 0018:ffffc90000a878b8 EFLAGS: 00000002 RAX: 1ffffffff37b7500 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020 RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: ffffffff857811b0 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff9bdbaae0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888123b52000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fef2f427dac CR3: 000000003405c000 CR4: 00000000003526f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:128 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline] wait_for_lsr+0x184/0x2f0 drivers/tty/serial/8250/8250_port.c:2013 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3270 [inline] __serial8250_console_fifo_write+0xcd/0x3e0 drivers/tty/serial/8250/8250_port.c:3345 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline] __serial8250_console_write drivers/tty/serial/8250/8250_port.c:3432 [inline] serial8250_console_write+0xa7e/0x1200 drivers/tty/serial/8250/8250_port.c:3496 nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1 nbcon_emit_one kernel/printk/nbcon.c:1157 [inline] nbcon_kthread_func+0x6d9/0x8d0 kernel/printk/nbcon.c:1271 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245