rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16778 (detected by 0, t=10503 jiffies, g=470593, q=9600) task:syz-executor.5 state:R running task stack:27520 pid:16778 ppid: 6768 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:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x7/0x60 kernel/kcov.c:197 Code: fd ff ff b9 ff ff ff ff ba 08 00 00 00 4d 8b 03 48 0f bd ca 49 8b 45 00 48 63 c9 e9 64 ff ff ff 0f 1f 00 65 8b 05 39 e4 8b 7e <89> c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 40 f0 01 00 a9 RSP: 0018:ffffc90002d8fa18 EFLAGS: 00000246 RAX: 0000000080000000 RBX: ffffc90002d8fad0 RCX: ffffc90013aa9000 RDX: 0000000000040000 RSI: ffffc90002d8fad0 RDI: ffff88817c8f59a0 RBP: ffff88817c8f59a0 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff885aab41 R11: 0000000000000000 R12: ffffc90002d8fad0 R13: ffff88817cbba098 R14: ffffffff8d3d2120 R15: 0000000000000001 sctp_v6_cmp_addr+0xf/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: 0033:0x7f5b89476709 Code: Unable to access opcode bytes at RIP 0x7f5b894766df. RSP: 002b:00007f5b869cc188 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f5b8957b020 RCX: 00007f5b89476709 RDX: 000000000000001c RSI: 0000000020000000 RDI: 0000000000000004 RBP: 00007f5b894d0cb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc9fb7fb3f R14: 00007f5b869cc300 R15: 0000000000022000 ---------------- Code disassembly (best guess), 3 bytes skipped: 0: b9 ff ff ff ff mov $0xffffffff,%ecx 5: ba 08 00 00 00 mov $0x8,%edx a: 4d 8b 03 mov (%r11),%r8 d: 48 0f bd ca bsr %rdx,%rcx 11: 49 8b 45 00 mov 0x0(%r13),%rax 15: 48 63 c9 movslq %ecx,%rcx 18: e9 64 ff ff ff jmpq 0xffffff81 1d: 0f 1f 00 nopl (%rax) 20: 65 8b 05 39 e4 8b 7e mov %gs:0x7e8be439(%rip),%eax # 0x7e8be460 * 27: 89 c1 mov %eax,%ecx <-- trapping instruction 29: 48 8b 34 24 mov (%rsp),%rsi 2d: 81 e1 00 01 00 00 and $0x100,%ecx 33: 65 48 8b 14 25 40 f0 mov %gs:0x1f040,%rdx 3a: 01 00 3c: a9 .byte 0xa9