INFO: task syz.0.423:7764 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.423 state:D stack:24384 pid:7764 tgid:7764 ppid:5837 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x149b/0x4fd0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1539 filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 do_sync_mmap_readahead+0x394/0x870 mm/filemap.c:3360 filemap_fault+0x6ac/0x1290 mm/filemap.c:3549 __do_fault+0x138/0x390 mm/memory.c:5320 do_shared_fault mm/memory.c:5819 [inline] do_fault mm/memory.c:5893 [inline] do_pte_missing+0x6ad/0x3330 mm/memory.c:4401 handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6580 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x71/0xd0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f5ac5557398 RSP: 002b:00007f5ac590fb88 EFLAGS: 00010246 RAX: 0000200000001240 RBX: 0000000000000004 RCX: 0030656c69662f2e RDX: 0000000000000008 RSI: 0030656c69662f2e RDI: 0000200000001240 RBP: 00007f5ac57e7da0 R08: 0000001b2ff20000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000009 R12: 00007f5ac57e618c R13: 00007f5ac57e6180 R14: fffffffffffffffe R15: 00007f5ac590fca0 INFO: task syz.0.423:7767 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.423 state:D stack:27168 pid:7767 tgid:7764 ppid:5837 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x149b/0x4fd0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1539 filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 do_sync_mmap_readahead+0x394/0x870 mm/filemap.c:3360 filemap_fault+0x6ac/0x1290 mm/filemap.c:3549 __do_fault+0x138/0x390 mm/memory.c:5320 do_shared_fault mm/memory.c:5819 [inline] do_fault mm/memory.c:5893 [inline] do_pte_missing+0x6ad/0x3330 mm/memory.c:4401 handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6580 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x71/0xd0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f5ac544d646 RSP: 002b:00007f5ac63ae4e8 EFLAGS: 00010202 RAX: 00008f0000509120 RBX: 000000000000000f RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000200000003800 RDI: 0000200000003800 RBP: 0000200000001000 R08: 0000000000009120 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: 00007f5ac63ae9a0 R14: 0000200000000000 R15: 0000200000001800 INFO: task syz.4.426:7775 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.426 state:D stack:25336 pid:7775 tgid:7775 ppid:5844 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x149b/0x4fd0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1539 filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 do_sync_mmap_readahead+0x66a/0x870 mm/filemap.c:3400 filemap_fault+0x6ac/0x1290 mm/filemap.c:3549 __do_fault+0x138/0x390 mm/memory.c:5320 do_shared_fault mm/memory.c:5819 [inline] do_fault mm/memory.c:5893 [inline] do_pte_missing+0x6ad/0x3330 mm/memory.c:4401 handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6580 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x71/0xd0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f350a6556b1 RSP: 002b:00007f350ab0fb50 EFLAGS: 00010246 RAX: 0000200000001ec0 RBX: 0000000000000004 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00005555649c83c8 RBP: 00007f350ab0fc58 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 00007f350a9e618c R13: 00007f350a9e6180 R14: fffffffffffffffe R15: 00007f350ab0fca0 INFO: task syz.4.426:7777 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.426 state:D stack:25592 pid:7777 tgid:7775 ppid:5844 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x149b/0x4fd0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1539 filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 filemap_get_pages+0x468/0x1dc0 mm/filemap.c:2690 filemap_splice_read+0x581/0xc60 mm/filemap.c:3079 do_splice_read fs/splice.c:982 [inline] splice_direct_to_actor+0x4a9/0xcc0 fs/splice.c:1086 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x181/0x270 fs/splice.c:1230 do_sendfile+0x4da/0x7e0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f350a78f749 RSP: 002b:00007f350b551038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f350a9e6090 RCX: 00007f350a78f749 RDX: 0000000000000000 RSI: 000000000000000a RDI: 000000000000000a RBP: 00007f350a813f91 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000002000fb R11: 0000000000000246 R12: 0000000000000000 R13: 00007f350a9e6128 R14: 00007f350a9e6090 R15: 00007f350ab0fa28 INFO: task syz.1.447:7862 blocked for more than 146 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.447 state:D stack:25336 pid:7862 tgid:7862 ppid:5846 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x149b/0x4fd0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1539 filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 do_sync_mmap_readahead+0x66a/0x870 mm/filemap.c:3400 filemap_fault+0x6ac/0x1290 mm/filemap.c:3549 __do_fault+0x138/0x390 mm/memory.c:5320 do_shared_fault mm/memory.c:5819 [inline] do_fault mm/memory.c:5893 [inline] do_pte_missing+0x6ad/0x3330 mm/memory.c:4401 handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6580 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x71/0xd0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f816de556b1 RSP: 002b:00007f816e30fb50 EFLAGS: 00010246 RAX: 0000200000000100 RBX: 0000000000000004 RCX: 0000000000000000 RDX: 0000000000001004 RSI: 0000000000000000 RDI: 000055558ade73c8 RBP: 00007f816e30fc58 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 00007f816e1e5fac R13: 00007f816e1e5fa0 R14: fffffffffffffffe R15: 00007f816e30fca0 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:13/3000: #0: ffff88813ff29948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813ff29948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000bc67bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000bc67bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8f311dc8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 2 locks held by getty/5592: #0: ffff888034ee50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211 2 locks held by kworker/1:6/5963: 4 locks held by kworker/u8:18/6726: #0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:647 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085 #3: ffffffff99b53180 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x87/0x540 lib/debugobjects.c:818 1 lock held by syz.0.423/7764: #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 2 locks held by syz.0.423/7765: #0: ffff888149107aa8 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff888149107aa8 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: blkdev_fallocate+0x260/0x530 block/fops.c:908 #1: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock include/linux/fs.h:1082 [inline] #1: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: blkdev_fallocate+0x290/0x530 block/fops.c:909 1 lock held by syz.0.423/7767: #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 1 lock held by syz.4.426/7775: #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 1 lock held by syz.4.426/7777: #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 1 lock held by syz.1.447/7862: #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 1 lock held by syz.3.478/8011: #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 1 lock held by syz.2.488/8060: #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 1 lock held by syz.2.488/8061: #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline] #0: ffff888149107c48 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe50 mm/readahead.c:494 5 locks held by syz.5.491/8077: #0: ffff88807b078ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] #0: ffff88807b078ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5b0 net/bluetooth/hci_core.c:2715 #1: ffff88807b0780c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x1100 net/bluetooth/hci_sync.c:5314 #2: ffffffff8f483988 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2143 [inline] #2: ffffffff8f483988 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2637 #3: ffff888079f59338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 net/bluetooth/l2cap_core.c:1763 #4: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #4: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x36e/0x6e0 kernel/rcu/tree_exp.h:956 3 locks held by syz-executor/8208: #0: ffff888032980ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] #0: ffff888032980ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5b0 net/bluetooth/hci_core.c:2715 #1: ffff8880329800c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x1100 net/bluetooth/hci_sync.c:5314 #2: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #2: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2b1/0x6e0 kernel/rcu/tree_exp.h:956 1 lock held by syz.8.603/8542: #0: ffff888149107aa8 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline] #0: ffff888149107aa8 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: blkdev_write_iter+0x50b/0x710 block/fops.c:801 1 lock held by syz.6.604/8545: #0: ffffffff8f311dc8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8f311dc8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436 3 locks held by syz-executor/8758: #0: ffff88807b454ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] #0: ffff88807b454ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5b0 net/bluetooth/hci_core.c:2715 #1: ffff88807b4540c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x1100 net/bluetooth/hci_sync.c:5314 #2: ffffffff8f483988 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2143 [inline] #2: ffffffff8f483988 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2637 3 locks held by syz.7.896/9709: #0: ffff888057cccec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] #0: ffff888057cccec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5b0 net/bluetooth/hci_core.c:2715 #1: ffff888057ccc0c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x1100 net/bluetooth/hci_sync.c:5314 #2: ffffffff8f483988 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2143 [inline] #2: ffffffff8f483988 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2637 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 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] __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:346 [inline] watchdog+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: 13 e3 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 73 c1 0e 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197e20 EFLAGS: 000002c2 RAX: 0000000000452259 RBX: ffffffff819713ee RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8d79201e RDI: ffffffff8bc083e0 RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8f822270 R13: 1ffff110038d4b70 R14: 0000000000000001 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125f1f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000365030 CR3: 000000001e7be000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000ffe6 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1be/0x4d0 kernel/sched/idle.c:332 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x147