rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10500 ticks this GP) idle=835/1/0x4000000000000000 softirq=172973/172973 fqs=0 (t=10502 jiffies g=341377 q=206) rcu: rcu_preempt kthread timer wakeup didn't happen for 10502 jiffies! g341377 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=128895 rcu: rcu_preempt kthread starved for 10505 jiffies! g341377 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28696 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4955 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6236 schedule+0xd3/0x270 kernel/sched/core.c:6315 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1966 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2139 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: 2935 Comm: syz-executor.4 Not tainted 5.15.0-rc4-next-20211005-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:438 [inline] RIP: 0010:lock_is_held_type+0xe4/0x140 kernel/locking/lockdep.c:5681 Code: f6 47 22 03 0f 95 c0 45 31 ed 44 39 f0 41 0f 94 c5 48 c7 c7 a0 04 8c 89 e8 a9 0d 00 00 b8 ff ff ff ff 65 0f c1 05 ac f3 ce 76 <83> f8 01 75 29 9c 58 f6 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 RSP: 0018:ffffc90004da75b8 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 0000000000000002 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000202 RDI: 0000000000000000 RBP: ffffffff8b9811a0 R08: 0000000000000000 R09: ffffffff8d6ec857 R10: fffffbfff1add90a R11: 0000000000000000 R12: ffff888031750000 R13: 0000000000000000 R14: 00000000ffffffff R15: ffff888031750a90 FS: 00007eff3be32700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3de829d718 CR3: 000000001a2a1000 CR4: 00000000003526e0 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_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x442/0x510 kernel/locking/lockdep.c:5608 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:373 [inline] __lock_sock_fast+0x3e/0xe0 net/core/sock.c:3305 lock_sock_fast include/net/sock.h:1671 [inline] mptcp_subflow_cleanup_rbuf net/mptcp/protocol.c:465 [inline] mptcp_cleanup_rbuf net/mptcp/protocol.c:499 [inline] mptcp_recvmsg+0xae8/0x27b0 net/mptcp/protocol.c:2069 inet6_recvmsg+0x11b/0x5e0 net/ipv6/af_inet6.c:659 sock_recvmsg_nosec net/socket.c:944 [inline] sock_recvmsg net/socket.c:962 [inline] sock_recvmsg net/socket.c:958 [inline] ____sys_recvmsg+0x2c4/0x600 net/socket.c:2628 ___sys_recvmsg+0x127/0x200 net/socket.c:2670 do_recvmmsg+0x24d/0x6d0 net/socket.c:2764 __sys_recvmmsg net/socket.c:2843 [inline] __do_sys_recvmmsg net/socket.c:2866 [inline] __se_sys_recvmmsg net/socket.c:2859 [inline] __x64_sys_recvmmsg+0x20b/0x260 net/socket.c:2859 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: 0033:0x7eff3e8bb8d9 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:00007eff3be32188 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007eff3e9bff60 RCX: 00007eff3e8bb8d9 RDX: 0000000000000001 RSI: 0000000020001280 RDI: 0000000000000003 RBP: 00007eff3e915cb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffd6e7d03f R14: 00007eff3be32300 R15: 0000000000022000 NMI backtrace for cpu 0 CPU: 0 PID: 2934 Comm: syz-executor.1 Not tainted 5.15.0-rc4-next-20211005-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:604 [inline] check_cpu_stall kernel/rcu/tree_stall.h:688 [inline] rcu_pending kernel/rcu/tree.c:3889 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2608 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 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:__kasan_check_read+0x8/0x10 mm/kasan/shadow.c:31 Code: db 0f 85 00 81 35 07 48 83 c4 60 5b 5d 41 5c 41 5d c3 c3 e9 00 82 35 07 cc cc cc cc cc cc cc cc cc cc 48 8b 0c 24 89 f6 31 d2 f3 f9 ff ff 0f 1f 00 48 8b 0c 24 89 f6 ba 01 00 00 00 e9 e0 f9 RSP: 0018:ffffc900048c7670 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff815bb251 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d6ec850 RBP: 1ffff92000918ed1 R08: 0000000000000000 R09: ffffffff8d6ec857 R10: fffffbfff1add90a R11: 0000000000000000 R12: ffff88802324a760 R13: dffffc0000000000 R14: 0000000000000001 R15: ffff88802324a760 instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] cpumask_test_cpu include/linux/cpumask.h:379 [inline] cpu_online include/linux/cpumask.h:921 [inline] trace_lock_release include/trace/events/lock.h:58 [inline] lock_release+0xa1/0x720 kernel/locking/lockdep.c:5648 unlock_sock_fast include/net/sock.h:1697 [inline] unlock_sock_fast include/net/sock.h:1690 [inline] mptcp_subflow_cleanup_rbuf net/mptcp/protocol.c:468 [inline] mptcp_cleanup_rbuf net/mptcp/protocol.c:499 [inline] mptcp_recvmsg+0xb94/0x27b0 net/mptcp/protocol.c:2069 inet6_recvmsg+0x11b/0x5e0 net/ipv6/af_inet6.c:659 sock_recvmsg_nosec net/socket.c:944 [inline] sock_recvmsg net/socket.c:962 [inline] sock_recvmsg net/socket.c:958 [inline] ____sys_recvmsg+0x2c4/0x600 net/socket.c:2628 ___sys_recvmsg+0x127/0x200 net/socket.c:2670 do_recvmmsg+0x24d/0x6d0 net/socket.c:2764 __sys_recvmmsg net/socket.c:2843 [inline] __do_sys_recvmmsg net/socket.c:2866 [inline] __se_sys_recvmmsg net/socket.c:2859 [inline] __x64_sys_recvmmsg+0x20b/0x260 net/socket.c:2859 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: 0033:0x7f5fb21018d9 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:00007f5faf678188 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f5fb2205f60 RCX: 00007f5fb21018d9 RDX: 0000000000000001 RSI: 0000000020001280 RDI: 0000000000000003 RBP: 00007f5fb215bcb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff3444c82f R14: 00007f5faf678300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: f6 47 22 03 testb $0x3,0x22(%rdi) 4: 0f 95 c0 setne %al 7: 45 31 ed xor %r13d,%r13d a: 44 39 f0 cmp %r14d,%eax d: 41 0f 94 c5 sete %r13b 11: 48 c7 c7 a0 04 8c 89 mov $0xffffffff898c04a0,%rdi 18: e8 a9 0d 00 00 callq 0xdc6 1d: b8 ff ff ff ff mov $0xffffffff,%eax 22: 65 0f c1 05 ac f3 ce xadd %eax,%gs:0x76cef3ac(%rip) # 0x76cef3d6 29: 76 * 2a: 83 f8 01 cmp $0x1,%eax <-- trapping instruction 2d: 75 29 jne 0x58 2f: 9c pushfq 30: 58 pop %rax 31: f6 c4 02 test $0x2,%ah 34: 75 3d jne 0x73 36: 48 f7 04 24 00 02 00 testq $0x200,(%rsp) 3d: 00 3e: 74 01 je 0x41