rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 0, t=10502 jiffies, g=108421, q=44) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295033922-4295023420), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g108421 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:28720 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6253 schedule+0xd2/0x260 kernel/sched/core.c:6326 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 29319 Comm: syz-executor.3 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline] RIP: 0010:lock_is_held_type+0xea/0x140 kernel/locking/lockdep.c:5682 Code: c0 45 31 ed 44 39 f0 41 0f 94 c5 48 c7 c7 40 f9 ab 89 e8 a9 0d 00 00 b8 ff ff ff ff 65 0f c1 05 8c 48 be 76 83 f8 01 75 29 9c <58> f6 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 44 RSP: 0018:ffffc90000fd8bf0 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000005 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000010004 RDI: 0000000000000000 RBP: ffffffff8bb810e0 R08: 0000000000000000 R09: ffffffff8d90efd7 R10: fffffbfff1b21dfa R11: 0000000000000000 R12: ffff88807b662080 R13: 0000000000000000 R14: 00000000ffffffff R15: ffff88807b662b80 FS: 00007fea215ab700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555555b43848 CR3: 000000007f0b8000 CR4: 00000000003526e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:125 trace_lock_release include/trace/events/lock.h:58 [inline] lock_release+0x522/0x720 kernel/locking/lockdep.c:5648 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x16/0x70 kernel/locking/spinlock.c:194 debug_object_activate+0x287/0x3e0 lib/debugobjects.c:689 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline] debug_activate kernel/time/hrtimer.c:475 [inline] enqueue_hrtimer+0x27/0x3e0 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1702 [inline] __hrtimer_run_queues+0xb02/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:finish_task_switch.isra.0+0x323/0xb80 kernel/sched/core.c:4852 Code: 13 54 f4 07 85 c0 75 02 0f 0b 48 85 db 0f 85 25 01 00 00 4c 89 f7 e8 fc f7 ff ff e8 37 4c 2d 00 fb 65 48 8b 1c 25 40 70 02 00 <48> 8d bb 80 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 RSP: 0018:ffffc900051cf578 EFLAGS: 00000202 RAX: 00000000000041cb RBX: ffff88807b662080 RCX: 1ffffffff1ff3dde RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900051cf5c0 R08: 0000000000000001 R09: ffffffff8ff76a6f R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880b9d3a858 R13: ffff888075996280 R14: ffff8880b9d39b00 R15: ffff8880b9d3a538 context_switch kernel/sched/core.c:4975 [inline] __schedule+0xaa2/0x4940 kernel/sched/core.c:6253 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:6668 irqentry_exit+0x31/0x80 kernel/entry/common.c:425 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:prefetchw arch/x86/include/asm/processor.h:741 [inline] RIP: 0010:slab_alloc mm/slab.c:3319 [inline] RIP: 0010:kmem_cache_alloc_trace+0x193/0x4a0 mm/slab.c:3573 Code: 0f 84 3e 01 00 00 4d 85 ff 48 89 54 24 10 0f 85 d4 01 00 00 9c 58 f6 c4 02 0f 85 e3 01 00 00 4d 85 ff 74 01 fb 48 8b 74 24 10 <0f> 0d 0e 0f 1f 44 00 00 48 83 7b 50 00 0f 84 83 00 00 00 44 23 25 RSP: 0018:ffffc900051cf7c0 EFLAGS: 00000206 RAX: 0000000000000002 RBX: ffff888010c40800 RCX: 1ffffffff1ff3dde RDX: 0000000000000000 RSI: ffff888029dd6000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff8ff76a6f R10: 0000000000000001 R11: 000000000000001f R12: 0000000000000dc0 R13: 0000000000000dc0 R14: 00000000000005f8 R15: 0000000000000200 kmalloc include/linux/slab.h:590 [inline] kzalloc include/linux/slab.h:724 [inline] usb_hub_create_port_device+0x71/0xd50 drivers/usb/core/port.c:537 hub_configure drivers/usb/core/hub.c:1655 [inline] hub_probe.cold+0x2479/0x2a73 drivers/usb/core/hub.c:1889 usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:517 [inline] really_probe+0x245/0xcc0 drivers/base/dd.c:596 __driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781 __device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427 __device_attach+0x228/0x4a0 drivers/base/dd.c:969 proc_ioctl.part.0+0x48e/0x560 drivers/usb/core/devio.c:2340 proc_ioctl drivers/usb/core/devio.c:170 [inline] proc_ioctl_default drivers/usb/core/devio.c:2375 [inline] usbdev_do_ioctl drivers/usb/core/devio.c:2731 [inline] usbdev_ioctl+0x2b29/0x36c0 drivers/usb/core/devio.c:2791 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fea22c35e99 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fea215ab168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fea22d48f60 RCX: 00007fea22c35e99 RDX: 0000000020000040 RSI: 00000000c0105512 RDI: 0000000000000004 RBP: 00007fea22c90031 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffeaeca64f R14: 00007fea215ab300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: c0 45 31 ed rolb $0xed,0x31(%rbp) 4: 44 39 f0 cmp %r14d,%eax 7: 41 0f 94 c5 sete %r13b b: 48 c7 c7 40 f9 ab 89 mov $0xffffffff89abf940,%rdi 12: e8 a9 0d 00 00 callq 0xdc0 17: b8 ff ff ff ff mov $0xffffffff,%eax 1c: 65 0f c1 05 8c 48 be xadd %eax,%gs:0x76be488c(%rip) # 0x76be48b0 23: 76 24: 83 f8 01 cmp $0x1,%eax 27: 75 29 jne 0x52 29: 9c pushfq * 2a: 58 pop %rax <-- trapping instruction 2b: f6 c4 02 test $0x2,%ah 2e: 75 3d jne 0x6d 30: 48 f7 04 24 00 02 00 testq $0x200,(%rsp) 37: 00 38: 74 01 je 0x3b 3a: fb sti 3b: 48 83 c4 08 add $0x8,%rsp 3f: 44 rex.R