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INFO: rcu detected stall in sctp_inet_connect (7)

Status: auto-obsoleted due to no activity on 2025/08/03 11:32
Subsystems: sctp
[Documentation on labels]
First crash: 528d, last: 413d
▶ ▼ Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sctp_inet_connect (2) mm 1 4 2357d 2442d 0/29 auto-closed as invalid on 2020/04/07 07:45
upstream INFO: rcu detected stall in sctp_inet_connect (8) prio:high sctp 1 5 105d 250d 0/29 auto-obsoleted due to no activity on 2026/06/07 00:09
upstream INFO: rcu detected stall in sctp_inet_connect (5) net 1 1 1114d 1114d 0/29 auto-obsoleted due to no activity on 2023/09/02 17:34
linux-4.19 INFO: rcu detected stall in sctp_inet_connect 1 2 2135d 2201d 0/1 auto-closed as invalid on 2020/12/15 01:43
upstream INFO: rcu detected stall in sctp_inet_connect (6) mm 1 1 637d 637d 0/29 auto-obsoleted due to no activity on 2024/12/22 03:14
upstream INFO: rcu detected stall in sctp_inet_connect (4) sctp 1 6 1677d 1779d 0/29 closed as invalid on 2022/02/08 10:00
upstream INFO: rcu detected stall in sctp_inet_connect (3) sctp 1 12 2044d 2255d 0/29 auto-closed as invalid on 2021/02/14 17:57
upstream INFO: rcu detected stall in sctp_inet_connect netfilter 1 1 2660d 2660d 0/29 auto-closed as invalid on 2019/09/07 12:17

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=a834/1/0x4000000000000000 softirq=59981/59982 fqs=2
rcu: 	(detected by 1, t=10502 jiffies, g=54605, q=93 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 14340 Comm: syz.6.2056 Not tainted 6.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:taprio_set_budgets+0x181/0x310 net/sched/sch_taprio.c:669
Code: 0f 4c 8b 70 20 0f 87 6e 01 00 00 4c 89 e8 48 c1 e8 03 42 80 3c 38 00 0f 85 4f 01 00 00 49 69 45 00 e8 03 00 00 31 d2 49 f7 f6 <49> 89 c6 e8 97 20 50 f8 49 83 fc 10 0f 87 e3 00 00 00 be 04 00 00
RSP: 0018:ffffc90000007d10 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff888032eed484 RCX: ffffffff8969bf0a
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888077d732e0
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffed100efae65c
R10: ffff888077d732e7 R11: 0000000000000003 R12: 0000000000000001
R13: ffff888032eed408 R14: 0000000000000190 R15: dffffc0000000000
FS:  00007efc31c086c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2ff2e9 CR3: 0000000058304000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 advance_sched+0x5e1/0xc60 net/sched/sch_taprio.c:977
 __run_hrtimer kernel/time/hrtimer.c:1801 [inline]
 __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1865
 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1927
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__sanitizer_cov_trace_pc+0x5a/0x70 kernel/kcov.c:223
Code: 35 8b 82 2c 16 00 00 85 c0 74 2b 8b 82 08 16 00 00 83 f8 02 75 20 48 8b 8a 10 16 00 00 8b 92 0c 16 00 00 48 8b 01 48 83 c0 01 <48> 39 d0 73 07 48 89 01 48 89 34 c1 c3 cc cc cc cc 0f 1f 44 00 00
RSP: 0018:ffffc9000c44f0b8 EFLAGS: 00000206
RAX: 0000000000012f33 RBX: 0000000000000000 RCX: ffffc90014c89000
RDX: 0000000000080000 RSI: ffffffff8a04f7b8 RDI: 0000000000000005
RBP: ffffc9000c44f1c8 R08: 0000000000000005 R09: 00000000fffffffd
R10: 00000000fffffffd R11: 0000000000000002 R12: 00000000fffffffd
R13: ffff88802379f8b8 R14: 1ffff92001889e27 R15: 0000000000000000
 find_match+0xc8/0x15d0 net/ipv6/route.c:770
 __find_rr_leaf+0x141/0xe00 net/ipv6/route.c:835
 find_rr_leaf net/ipv6/route.c:856 [inline]
 rt6_select net/ipv6/route.c:900 [inline]
 fib6_table_lookup+0x57e/0xa30 net/ipv6/route.c:2195
 ip6_pol_route+0x1cd/0x1120 net/ipv6/route.c:2231
 pol_lookup_func include/net/ip6_fib.h:616 [inline]
 fib6_rule_lookup+0x386/0x720 net/ipv6/fib6_rules.c:124
 ip6_route_output_flags_noref net/ipv6/route.c:2639 [inline]
 ip6_route_output_flags+0x1d0/0x640 net/ipv6/route.c:2651
 ip6_dst_lookup_tail.constprop.0+0x1159/0x2150 net/ipv6/ip6_output.c:1156
 ip6_dst_lookup_flow+0x99/0x1d0 net/ipv6/ip6_output.c:1259
 sctp_v6_get_dst+0x6a3/0x2050 net/sctp/ipv6.c:326
 sctp_transport_route+0x12e/0x350 net/sctp/transport.c:455
 sctp_assoc_add_peer+0x743/0x1530 net/sctp/associola.c:663
 sctp_connect_new_asoc+0x209/0x790 net/sctp/socket.c:1099
 __sctp_connect+0x3f5/0xc60 net/sctp/socket.c:1197
 sctp_connect net/sctp/socket.c:4819 [inline]
 sctp_inet_connect+0x15f/0x200 net/sctp/socket.c:4834
 __sys_connect_file+0x13e/0x1a0 net/socket.c:2045
 __sys_connect+0x14f/0x170 net/socket.c:2064
 __do_sys_connect net/socket.c:2070 [inline]
 __se_sys_connect net/socket.c:2067 [inline]
 __x64_sys_connect+0x72/0xb0 net/socket.c:2067
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efc30d8d169
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007efc31c08038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00007efc30fa5fa0 RCX: 00007efc30d8d169
RDX: 000000000000001c RSI: 0000400000000000 RDI: 0000000000000003
RBP: 00007efc30e0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007efc30fa5fa0 R15: 00007ffe066dc348
 </TASK>
rcu: rcu_preempt kthread starved for 10485 jiffies! g54605 f0x0 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:27552 pid:17    tgid:17    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0xf43/0x5890 kernel/sched/core.c:6765
 __schedule_loop kernel/sched/core.c:6842 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6857
 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 4182 Comm: kworker/u8:8 Not tainted 6.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x4cb/0x12c0 kernel/smp.c:885
Code: 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 fc 4c 89 fd 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 7c 0e 0c 00 f3 90 41 0f b6 04 24 <40> 38 c5 7c 08 84 c0 0f 85 e8 0b 00 00 8b 43 08 31 ff 83 e0 01 41
RSP: 0018:ffffc9000eb97928 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b8646a00 RCX: ffffffff81add19a
RDX: ffff888034c1a440 RSI: ffffffff81add174 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000006 R12: ffffed10170c8d41
R13: 0000000000000001 R14: ffff8880b873fe80 R15: ffff8880b8646a08
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efc31c07f98 CR3: 000000000df80000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000c DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2118 [inline]
 text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2328
 text_poke_flush arch/x86/kernel/alternative.c:2519 [inline]
 text_poke_flush arch/x86/kernel/alternative.c:2516 [inline]
 text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2526
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 jump_label_update+0x1d7/0x400 kernel/jump_label.c:920
 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 toggle_allocation_gate mm/kfence/core.c:850 [inline]
 toggle_allocation_gate+0xfc/0x260 mm/kfence/core.c:842
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3317 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/25 02:44 upstream d082ecbc71e9 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sctp_inet_connect
2025/02/09 02:08 upstream 595ab66f1bec ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sctp_inet_connect
2025/01/10 09:47 upstream 2144da25584e 67d7ec0a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in sctp_inet_connect
2025/05/05 11:21 upstream 92a09c47464d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in sctp_inet_connect
* Struck through repros no longer work on HEAD.