rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (0 ticks this GP) idle=5e1/1/0x4000000000000000 softirq=57381/57381 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P24870/1:b..l P24873/1:b..l P19131/1:b..l (detected by 1, t=10502 jiffies, g=93973, q=48) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1 Comm: systemd Not tainted 5.16.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:lock_acquire+0x81/0x4d0 kernel/locking/lockdep.c:5605 Code: 4c 8d 6c 24 40 49 c1 ed 03 48 b8 f1 f1 f1 f1 00 f2 f2 f2 4b 89 44 3d 00 43 c7 44 3d 09 f2 f2 f2 00 43 c7 44 3d 11 f3 f3 f3 f3 <66> 43 c7 44 3d 15 f3 f3 43 c6 44 3d 17 f3 89 54 24 1c 4c 89 44 24 RSP: 0018:ffffc90000007b20 EFLAGS: 00000806 RAX: f2f2f200f1f1f1f1 RBX: ffff8880b9a2a258 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880b9a2a258 RBP: ffffc90000007c68 R08: 0000000000000001 R09: 0000000000000000 R10: fffffbfff1c3d206 R11: 0000000000000000 R12: 0000000000000000 R13: 1ffff92000000f6c R14: 0000000000000000 R15: dffffc0000000000 FS: 00007feccd45e500(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055b8ed3d10b0 CR3: 000000007ef89000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1689 [inline] __hrtimer_run_queues+0x546/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:debug_check_no_locks_freed+0x2c6/0x9b0 kernel/locking/lockdep.c:6425 Code: 00 00 00 fc ff df f6 44 24 61 02 48 8b 5c 24 38 0f 85 7c 04 00 00 f7 44 24 30 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <48> c7 04 1a 00 00 00 00 48 c7 44 1a 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc90000c67740 EFLAGS: 00000206 RAX: 0000000000000000 RBX: 1ffff9200018cef0 RCX: 0000000000000002 RDX: dffffc0000000000 RSI: ffff888140780000 RDI: ffff888140780a58 RBP: ffffc90000c67850 R08: dffffc0000000000 R09: ffffc90000c67a20 R10: fffff5200018cf4e R11: 0000000000000000 R12: 0000000000000002 R13: ffff888140780a98 R14: ffffc90000c677a0 R15: 1ffff110280f0153 __raw_spin_lock_init+0x27/0x100 kernel/locking/spinlock_debug.c:23 __init_waitqueue_head+0x34/0xd0 kernel/sched/wait.c:11 lookup_open fs/namei.c:3195 [inline] open_last_lookups fs/namei.c:3350 [inline] path_openat+0x914/0x3660 fs/namei.c:3556 do_filp_open+0x277/0x4f0 fs/namei.c:3586 do_sys_openat2+0x13b/0x500 fs/open.c:1212 do_sys_open fs/open.c:1228 [inline] __do_sys_open fs/open.c:1236 [inline] __se_sys_open fs/open.c:1232 [inline] __x64_sys_open+0x221/0x270 fs/open.c:1232 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7feccbcfb85d Code: bb 20 00 00 75 10 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 b8 02 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 67 f6 ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffed41ee500 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007feccbcfb85d RDX: 00000000000001a4 RSI: 0000000000080141 RDI: 000055b8ed3c9360 RBP: 000055b8ed3c9360 R08: 0000000000002000 R09: 00000000ffffffff R10: 000055b8ed3c9340 R11: 0000000000000293 R12: 00071afd498d0248 R13: 00000000ffffffff R14: 00000000ffffffff R15: 0000000000000002 task:kworker/u4:10 state:R running task stack:22408 pid:19131 ppid: 2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xb72/0x1460 kernel/sched/core.c:6253 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6668 irqentry_exit+0x56/0x90 kernel/entry/common.c:425 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:lock_acquire+0x21f/0x4d0 kernel/locking/lockdep.c:5641 Code: 08 4c 89 f7 e8 32 6a 6a 00 f6 84 24 81 00 00 00 02 0f 85 13 02 00 00 41 f7 c4 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 04 2f 00 00 00 00 43 c7 44 2f 09 00 00 00 00 43 c7 44 2f 11 RSP: 0018:ffffc90003f3f8e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920007e7f2c RCX: ffff88802a692758 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003f3fa40 R08: dffffc0000000000 R09: fffffbfff2034ddd R10: fffffbfff2034ddd R11: 0000000000000000 R12: 0000000000000246 R13: 1ffff920007e7f24 R14: ffffc90003f3f960 R15: dffffc0000000000 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:268 rcu_read_lock include/linux/rcupdate.h:688 [inline] inet_twsk_purge+0x11b/0x890 net/ipv4/inet_timewait_sock.c:268 ops_exit_list net/core/net_namespace.c:171 [inline] cleanup_net+0x7ec/0xc50 net/core/net_namespace.c:593 process_one_work+0x853/0x1140 kernel/workqueue.c:2298 worker_thread+0xac1/0x1320 kernel/workqueue.c:2445 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 task:syz-executor.1 state:R running task stack:26864 pid:24873 ppid: 8432 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xb72/0x1460 kernel/sched/core.c:6253 preempt_schedule_common kernel/sched/core.c:6419 [inline] preempt_schedule+0x14d/0x190 kernel/sched/core.c:6444 preempt_schedule_thunk+0x16/0x18 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x128/0x130 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:404 [inline] timerfd_clock_was_set+0x1d3/0x2b0 fs/timerfd.c:113 clock_was_set+0x8a0/0x940 kernel/time/hrtimer.c:980 do_settimeofday64+0x618/0x7a0 kernel/time/timekeeping.c:1327 __do_sys_clock_settime kernel/time/posix-timers.c:1079 [inline] __se_sys_clock_settime kernel/time/posix-timers.c:1067 [inline] __x64_sys_clock_settime+0x23d/0x280 kernel/time/posix-timers.c:1067 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f8f71edaae9 RSP: 002b:00007f8f6f450188 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3 RAX: ffffffffffffffda RBX: 00007f8f71fedf60 RCX: 00007f8f71edaae9 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000000 RBP: 00007f8f71f34f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd9c090e6f R14: 00007f8f6f450300 R15: 0000000000022000 task:syz-executor.0 state:R running task stack:26864 pid:24870 ppid: 6551 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xb72/0x1460 kernel/sched/core.c:6253 preempt_schedule_common kernel/sched/core.c:6419 [inline] preempt_schedule+0x14d/0x190 kernel/sched/core.c:6444 preempt_schedule_thunk+0x16/0x18 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:389 [inline] filemap_map_pages+0x9ca/0xb50 mm/filemap.c:3346 do_fault_around mm/memory.c:4143 [inline] do_read_fault+0x39b/0x650 mm/memory.c:4158 do_fault mm/memory.c:4293 [inline] handle_pte_fault mm/memory.c:4551 [inline] __handle_mm_fault mm/memory.c:4686 [inline] handle_mm_fault+0x1849/0x2560 mm/memory.c:4784 do_user_addr_fault+0x8cc/0x10c0 arch/x86/mm/fault.c:1397 handle_page_fault arch/x86/mm/fault.c:1485 [inline] exc_page_fault+0xa1/0x1e0 arch/x86/mm/fault.c:1541 asm_exc_page_fault+0x1e/0x30 RIP: 0033:0x7fc10d062186 RSP: 002b:00007ffc89d1f928 EFLAGS: 00010287 RAX: 00007fc10d1d9008 RBX: 0000000000000003 RCX: 00007fc10d1d9000 RDX: 00007fc10d1d9000 RSI: 00007ffc89d1f910 RDI: 00007ffc89d1f9e8 RBP: 00007ffc89d1f9e8 R08: 00007fc10d5d9000 R09: 0000000000000010 R10: 00007ffc89d290b8 R11: 0000000000021bba R12: 0000000000000001 R13: 0000000000000000 R14: 00007fc10d1d4f60 R15: 00000000000ab120 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g93973 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=36042 rcu: rcu_preempt kthread starved for 10502 jiffies! g93973 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 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:I stack:26576 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xb72/0x1460 kernel/sched/core.c:6253 schedule+0x12b/0x1f0 kernel/sched/core.c:6326 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x1fd/0x770 kernel/rcu/tree.c:1955 rcu_gp_kthread+0xa5/0x350 kernel/rcu/tree.c:2128 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: ---------------- Code disassembly (best guess): 0: 4c 8d 6c 24 40 lea 0x40(%rsp),%r13 5: 49 c1 ed 03 shr $0x3,%r13 9: 48 b8 f1 f1 f1 f1 00 movabs $0xf2f2f200f1f1f1f1,%rax 10: f2 f2 f2 13: 4b 89 44 3d 00 mov %rax,0x0(%r13,%r15,1) 18: 43 c7 44 3d 09 f2 f2 movl $0xf2f2f2,0x9(%r13,%r15,1) 1f: f2 00 21: 43 c7 44 3d 11 f3 f3 movl $0xf3f3f3f3,0x11(%r13,%r15,1) 28: f3 f3 * 2a: 66 43 c7 44 3d 15 f3 movw $0xf3f3,0x15(%r13,%r15,1) <-- trapping instruction 31: f3 32: 43 c6 44 3d 17 f3 movb $0xf3,0x17(%r13,%r15,1) 38: 89 54 24 1c mov %edx,0x1c(%rsp) 3c: 4c rex.WR 3d: 89 .byte 0x89 3e: 44 rex.R 3f: 24 .byte 0x24