rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P24561 (detected by 0, t=10502 jiffies, g=233649, q=3886) task:syz-executor.5 state:R running task stack:27600 pid:24561 ppid: 6853 flags:0x00004006 Call Trace: sched_show_task kernel/sched/core.c:8545 [inline] sched_show_task+0x433/0x5b0 kernel/sched/core.c:8519 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:227 [inline] print_other_cpu_stall kernel/rcu/tree_stall.h:567 [inline] check_cpu_stall kernel/rcu/tree_stall.h:729 [inline] rcu_pending kernel/rcu/tree.c:3880 [inline] rcu_sched_clock_irq+0x1fa5/0x2200 kernel/rcu/tree.c:2599 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:1421 __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:ipv6_addr_equal include/net/ipv6.h:580 [inline] RIP: 0010:__sctp_v6_cmp_addr+0x26f/0x520 net/sctp/ipv6.c:644 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 5c 02 00 00 48 8d 7b 10 4c 33 75 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 43 02 00 00 48 8d 7d 10 4c 8b 63 10 48 b8 00 00 RSP: 0018:ffffc900035479f0 EFLAGS: 00000a06 RAX: dffffc0000000000 RBX: ffff888071fedca0 RCX: ffffc900140c2000 RDX: 1ffff1100e3fdb96 RSI: ffffffff8860cd74 RDI: ffff888071fedcb0 RBP: ffffc90003547ad0 R08: 0000000000000000 R09: 000000000000000a R10: ffffffff8860cbdb R11: 000000000000000a R12: 000000000000000a R13: ffff888071fedca8 R14: 0000000000000000 R15: 0000000000000001 sctp_v6_cmp_addr+0x1a/0xd0 net/sctp/ipv6.c:662 sctp_bind_addr_state+0x103/0x1d0 net/sctp/bind_addr.c:407 sctp_copy_local_addr_list+0x1fe/0x4f0 net/sctp/protocol.c:163 sctp_copy_one_addr net/sctp/bind_addr.c:460 [inline] sctp_bind_addr_copy+0xde/0x460 net/sctp/bind_addr.c:56 sctp_connect_new_asoc+0x1cd/0x770 net/sctp/socket.c:1092 __sctp_connect+0x3d0/0xc30 net/sctp/socket.c:1194 sctp_connect net/sctp/socket.c:4808 [inline] sctp_inet_connect+0x15e/0x200 net/sctp/socket.c:4823 __sys_connect_file+0x155/0x1a0 net/socket.c:1896 __sys_connect+0x161/0x190 net/socket.c:1913 __do_sys_connect net/socket.c:1923 [inline] __se_sys_connect net/socket.c:1920 [inline] __x64_sys_connect+0x6f/0xb0 net/socket.c:1920 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: 0033:0x7f5a715f9739 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:00007f5a6eb70188 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f5a716fdf80 RCX: 00007f5a715f9739 RDX: 000000000000001c RSI: 0000000020000280 RDI: 0000000000000005 RBP: 00007f5a71653cc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5a716fdf80 R13: 00007ffcbda02b8f R14: 00007f5a6eb70300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 48 89 fa mov %rdi,%rdx 3: 48 c1 ea 03 shr $0x3,%rdx 7: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) b: 0f 85 5c 02 00 00 jne 0x26d 11: 48 8d 7b 10 lea 0x10(%rbx),%rdi 15: 4c 33 75 08 xor 0x8(%rbp),%r14 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 20: fc ff df 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 43 02 00 00 jne 0x277 34: 48 8d 7d 10 lea 0x10(%rbp),%rdi 38: 4c 8b 63 10 mov 0x10(%rbx),%r12 3c: 48 rex.W 3d: b8 .byte 0xb8