INFO: task syz.0.575:7914 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.575 state:D stack:27712 pid:7914 tgid:7912 ppid:5822 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5264 [inline] __schedule+0x1848/0x4ec0 kernel/sched/core.c:6872 __schedule_loop kernel/sched/core.c:6954 [inline] schedule+0x165/0x360 kernel/sched/core.c:6969 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7026 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 bdev_open+0xe0/0xd30 block/bdev.c:945 blkdev_open+0x457/0x600 block/fops.c:702 do_dentry_open+0x953/0x13f0 fs/open.c:962 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:3975 [inline] path_openat+0x2efb/0x3860 fs/namei.c:4134 do_filp_open+0x1fa/0x410 fs/namei.c:4161 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: 0033:0x7f5e6a38df10 RSP: 002b:00007f5e6b14cb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000180380 RCX: 00007f5e6a38df10 RDX: 0000000000180380 RSI: 00007f5e6b14cc10 RDI: 00000000ffffff9c RBP: 00007f5e6b14cc10 R08: 0000000000000000 R09: 002364626e2f7665 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007f5e6a5e6128 R14: 00007f5e6a5e6090 R15: 00007ffd65af81b8 Showing all locks held in the system: 5 locks held by kworker/0:0/9: #0: ffff888142e80d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x841/0x15d0 kernel/workqueue.c:3242 #1: ffffc900000e7b80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x868/0x15d0 kernel/workqueue.c:3243 #2: ffff888028a96198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff888028a96198 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4ef0 drivers/usb/core/hub.c:5899 #3: ffff888028ad1518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff888028ad1518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff888028ad1518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff888028ad1518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff888028ad1518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x215a/0x4ef0 drivers/usb/core/hub.c:5953 #4: ffff8880285c1168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff8880285c1168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff8880285c1168 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff8880285c1168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x2182/0x4ef0 drivers/usb/core/hub.c:5953 1 lock held by khungtaskd/31: #0: ffffffff8e33b720 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e33b720 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e33b720 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5585: #0: ffff88814d1b20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by udevd/5840: #0: ffff8880259eb358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 1 lock held by udevd/6311: #0: ffff88802598d358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 1 lock held by syz.0.575/7914: #0: ffff88802598d358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 1 lock held by syz.4.920/9299: #0: ffff88802598d358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1288 2 locks held by syz.5.1287/10627: 2 locks held by syz.3.1296/10653: #0: ffff88807ba37ac8 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1051 [inline] #0: ffff88807ba37ac8 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline] #0: ffff88807ba37ac8 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1459 #1: ffffffff8e3411f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8e3411f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957 ============================================= 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:336 [inline] watchdog+0xfa9/0xff0 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 10627 Comm: syz.5.1287 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:check_kcov_mode kernel/kcov.c:185 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x31/0x70 kernel/kcov.c:217 Code: 24 65 48 8b 0c 25 08 70 ba 92 65 8b 15 e8 9f f8 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 84 16 00 00 00 74 2c <8b> 91 60 16 00 00 83 fa 02 75 21 48 8b 91 68 16 00 00 48 8b 32 48 RSP: 0018:ffffc9000efaea38 EFLAGS: 00000246 RAX: ffffffff820b9642 RBX: 1ffff1100fe21f42 RCX: ffff88807ee08000 RDX: 0000000000000000 RSI: 0000000000000027 RDI: 0000000000000040 RBP: 800000007b72a067 R08: ffff88807ee08007 R09: 1ffff1100fdc1000 R10: dffffc0000000000 R11: ffffed100fdc1001 R12: ffff88806f1be000 R13: 1ffff1100de37cfe R14: ffff88806f1be7f0 R15: 00007f2a0afa4000 FS: 00007f2a0b2636c0(0000) GS:ffff888125b79000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffb67fb4198 CR3: 000000006f1be000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: _static_cpu_has arch/x86/include/asm/cpufeature.h:101 [inline] pgd_bad arch/x86/include/asm/pgtable.h:1146 [inline] follow_page_mask mm/gup.c:1020 [inline] __get_user_pages+0x1a02/0x29f0 mm/gup.c:1426 __get_user_pages_locked mm/gup.c:1692 [inline] get_dump_page+0x1ac/0x3f0 mm/gup.c:2192 dump_user_range+0x1de/0xc90 fs/coredump.c:1366 elf_core_dump+0x3369/0x3960 fs/binfmt_elf.c:2111 coredump_write+0x116c/0x1900 fs/coredump.c:1049 do_coredump fs/coredump.c:1126 [inline] vfs_coredump+0x3321/0x3e60 fs/coredump.c:1200 get_signal+0x1108/0x1340 kernel/signal.c:3019 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop kernel/entry/common.c:75 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline] irqentry_exit+0x171/0x640 kernel/entry/common.c:196 exc_page_fault+0xab/0x100 arch/x86/mm/fault.c:1535 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 002b:0000200000001348 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f2a0a5e5fa0 RCX: 00007f2a0a38f6c9 RDX: 0000000000000000 RSI: 0000200000001340 RDI: 0000000000002000 RBP: 00007f2a0a411f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f2a0a5e6038 R14: 00007f2a0a5e5fa0 R15: 00007fff346404e8