INFO: task syz.1.1921:12948 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.1.1921 state:D stack:27480 pid:12948 tgid:12946 ppid:5649 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 rwsem_down_write_slowpath+0x883/0x1080 kernel/locking/rwsem.c:1215 __down_write_common kernel/locking/rwsem.c:1347 [inline] __down_write kernel/locking/rwsem.c:1356 [inline] down_write+0x1bc/0x200 kernel/locking/rwsem.c:1626 inode_lock include/linux/fs.h:1029 [inline] blkdev_fallocate+0x260/0x530 block/fops.c:907 vfs_fallocate+0x669/0x7e0 fs/open.c:338 ksys_fallocate fs/open.c:362 [inline] __do_sys_fallocate fs/open.c:367 [inline] __se_sys_fallocate fs/open.c:365 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:365 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f399e19ce59 RSP: 002b:00007f399f000028 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f399e416090 RCX: 00007f399e19ce59 RDX: 0000000000000600 RSI: 0000000000000011 RDI: 0000000000000004 RBP: 00007f399e232d6f R08: 0000000000000000 R09: 0000000000000000 R10: 000000000007c000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f399e416128 R14: 00007f399e416090 R15: 00007f399e53fa48 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e95cc20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e95cc20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e95cc20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5388: #0: ffff8880360fe0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211 2 locks held by syz.4.1897/12843: #0: ffff888023094168 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888023094168 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: blkdev_fallocate+0x260/0x530 block/fops.c:907 #1: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock include/linux/fs.h:1084 [inline] #1: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: blkdev_fallocate+0x290/0x530 block/fops.c:908 1 lock held by syz.1.1921/12948: #0: ffff888023094168 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888023094168 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: blkdev_fallocate+0x260/0x530 block/fops.c:907 2 locks held by syz.8.2138/13852: #0: ffff888036460948 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #1: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_fault+0x95e/0x1300 mm/filemap.c:3562 2 locks held by syz.8.2138/13853: #0: ffff8880558b27f8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline] #0: ffff8880558b27f8 (&mm->mmap_lock){++++}-{4:4}, at: __mm_populate+0x182/0x390 mm/gup.c:1942 #1: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #1: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_fault+0x95e/0x1300 mm/filemap.c:3562 1 lock held by syz.7.2154/13914: #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe80 mm/readahead.c:497 1 lock held by syz.7.2154/13915: #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe80 mm/readahead.c:497 1 lock held by syz.6.2182/14007: #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe80 mm/readahead.c:497 1 lock held by syz.3.2233/14344: #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe80 mm/readahead.c:497 1 lock held by syz.3.2233/14345: #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe80 mm/readahead.c:497 1 lock held by syz.0.2266/14546: #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe80 mm/readahead.c:497 1 lock held by syz.0.2266/14548: #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe80 mm/readahead.c:497 1 lock held by syz.0.2266/14549: #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe80 mm/readahead.c:497 1 lock held by syz.9.2288/14665: #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe80 mm/readahead.c:497 1 lock held by syz.9.2288/14669: #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline] #0: ffff888023094300 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x37a/0xe80 mm/readahead.c:497 1 lock held by syz.2.2334/14971: #0: ffffffff8e962f28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #0: ffffffff8e962f28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 1 lock held by syz.8.2315/14981: #0: ffffffff8e962df8 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828 2 locks held by syz.4.2340/14995: ============================================= 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 05/09/2026 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:162 [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+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x389/0x470 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: 5750 Comm: kworker/1:8 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: usb_hub_wq hub_event RIP: 0010:rcu_read_lock_any_held+0x48/0x90 kernel/rcu/update.c:387 Code: 84 c0 74 44 48 c7 c7 20 cc 95 8e be ff ff ff ff e8 6d 9b fd 09 85 c0 75 2a 48 c7 c7 80 cc 95 8e be ff ff ff ff e8 58 9b fd 09 <85> c0 75 15 48 c7 c7 e0 cc 95 8e be ff ff ff ff e8 43 9b fd 09 85 RSP: 0018:ffffc90000a08c58 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000080010003 RDX: 0000000000000000 RSI: ffffffff8e217295 RDI: ffffffff8c28b9e0 RBP: 0000000000000006 R08: ffff88801bed8167 R09: 1ffff110037db02c R10: dffffc0000000000 R11: ffffed10037db02d R12: 0000000000000001 R13: ffff88807e835d00 R14: 0000000000000001 R15: ffffffff8e262798 FS: 0000000000000000(0000) GS:ffff8881253a0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000208030 CR3: 00000000808f0000 CR4: 00000000003526f0 DR0: 0000000000000004 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: select_idle_sibling kernel/sched/fair.c:8187 [inline] select_task_rq_fair+0xbb0/0x43b0 kernel/sched/fair.c:8891 select_task_rq kernel/sched/core.c:3579 [inline] try_to_wake_up+0x4db/0x1380 kernel/sched/core.c:4290 hrtimer_wakeup+0x4e/0x60 kernel/time/hrtimer.c:2191 __run_hrtimer kernel/time/hrtimer.c:1930 [inline] __hrtimer_run_queues+0x3c0/0xa20 kernel/time/hrtimer.c:1994 hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline] RIP: 0010:vprintk_emit+0x45d/0x560 kernel/printk/printk.c:2478 Code: 0f 84 44 ff ff ff e8 b2 2b 21 00 fb eb 44 e8 aa 2b 21 00 e8 f5 e8 02 0a 4d 85 f6 74 94 e8 9b 2b 21 00 fb 48 c7 c7 40 f0 94 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 cb 18 RSP: 0018:ffffc90004b17380 EFLAGS: 00000283 RAX: ffffffff81a48c45 RBX: ffffffff81a48abf RCX: 0000000000100000 RDX: ffffc9001a3ec000 RSI: 0000000000010f28 RDI: ffffffff8e94f040 RBP: ffffc90004b17430 R08: ffffffff903036f7 R09: 1ffffffff20606de R10: dffffc0000000000 R11: fffffbfff20606df R12: 0000000000000000 R13: 0000000000000029 R14: 0000000000000200 R15: 1ffff92000962e74 dev_vprintk_emit+0x355/0x420 drivers/base/core.c:4930 dev_printk_emit+0xee/0x140 drivers/base/core.c:4941 _dev_info+0x11e/0x180 drivers/base/core.c:4999 usb_disconnect+0xdd/0x990 drivers/usb/core/hub.c:2327 hub_port_connect drivers/usb/core/hub.c:5407 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x1cc9/0x4f30 drivers/usb/core/hub.c:5953 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 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