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INFO: rcu detected stall in sctp_setsockopt

Status: auto-obsoleted due to no activity on 2025/01/29 14:06
Reported-by: syzbot+1b5b5a2159f723c58ab0@syzkaller.appspotmail.com
First crash: 637d, last: 637d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sctp_setsockopt net 1 8 2503d 2709d 0/29 auto-closed as invalid on 2019/12/12 00:34
linux-4.19 INFO: rcu detected stall in sctp_setsockopt 1 3 2180d 2228d 0/1 auto-closed as invalid on 2020/11/28 08:55
linux-5.15 INFO: rcu detected stall in sctp_setsockopt (2) 1 2 3d20h 53d 0/3 upstream: reported on 2026/05/28 16:14
upstream INFO: rcu detected stall in sctp_setsockopt (2) sctp 1 8 2150d 2289d 0/29 auto-closed as invalid on 2020/11/28 11:26
linux-6.1 INFO: rcu detected stall in sctp_setsockopt 1 1 79d 79d 0/3 upstream: reported on 2026/05/02 14:43

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=355/1/0x4000000000000000 softirq=25327/25329 fqs=291 
	(detected by 0, t=10502 jiffies, g=32581, q=568)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8492 Comm: syz.0.1789 Not tainted 5.15.168-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__lock_acquire+0x2ae/0x1ff0
Code: 3d 0e d4 86 0c 00 0f 85 b5 12 00 00 48 c7 c7 20 29 8b 8a 48 c7 c6 c0 51 8b 8a e8 dd 49 e9 ff 0f 0b 31 f6 e9 9b 12 00 00 31 c0 <44> 89 64 24 70 44 89 74 24 54 49 8d 8d f0 0a 00 00 4c 8d 34 80 4c
RSP: 0018:ffffc90000dd0a60 EFLAGS: 00000046
RAX: 0000000000000002 RBX: ffff88801ee3a8f8 RCX: ffffffff96869f03
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff888024c83b00
RBP: 0000000000000002 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
R13: ffff88801ee39dc0 R14: 0000000000000000 R15: 0000000000000000
FS:  00007fc3014fd6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3291eff8 CR3: 000000001e59b000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:363 [inline]
 advance_sched+0x47/0x940 net/sched/sch_taprio.c:716
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x598/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:226 [inline]
RIP: 0010:__sanitizer_cov_trace_cmp4+0x4/0x80 kernel/kcov.c:267
Code: 89 f8 89 f6 48 c7 44 0a 08 02 00 00 00 48 89 44 0a 10 48 89 74 0a 18 4c 89 44 0a 20 49 ff c1 4c 89 09 c3 0f 1f 00 4c 8b 04 24 <65> 48 8b 15 24 fb 81 7e 65 8b 05 25 fb 81 7e 25 00 01 ff 00 74 10
RSP: 0018:ffffc90002f278a0 EFLAGS: 00000297
RAX: 0000000000000002 RBX: 0000000000000003 RCX: 0000000002f27903
RDX: ffff88801ee39dc0 RSI: 000000000000000a RDI: 0000000000000003
RBP: 000000000000000a R08: ffffffff899c7e87 R09: ffffffff892d75e4
R10: 0000000000000002 R11: ffff88801ee39dc0 R12: 00000000000080fe
R13: ffff88801f1e3aa8 R14: dffffc0000000000 R15: 00000000000080fe
 __sctp_v6_cmp_addr+0x2f7/0x520
 sctp_v6_cmp_addr+0x1c/0xc0 net/sctp/ipv6.c:662
 sctp_bind_addr_state+0xcb/0x1a0 net/sctp/bind_addr.c:413
 sctp_copy_local_addr_list+0x2ad/0x4c0 net/sctp/protocol.c:163
 sctp_bind_addr_copy+0x172/0x3b0 net/sctp/bind_addr.c:68
 sctp_connect_new_asoc+0x2e5/0x6a0 net/sctp/socket.c:1092
 __sctp_connect+0x657/0xe10 net/sctp/socket.c:1194
 __sctp_setsockopt_connectx net/sctp/socket.c:1333 [inline]
 sctp_setsockopt_connectx+0x17d/0x290 net/sctp/socket.c:1360
 sctp_setsockopt+0x836/0x10d0 net/sctp/socket.c:4616
 __sys_setsockopt+0x57e/0x990 net/socket.c:2203
 __do_sys_setsockopt net/socket.c:2214 [inline]
 __se_sys_setsockopt net/socket.c:2211 [inline]
 __x64_sys_setsockopt+0xb1/0xc0 net/socket.c:2211
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc303084ff9
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:00007fc3014fd038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007fc30323cf80 RCX: 00007fc303084ff9
RDX: 000000000000006e RSI: 0000000000000084 RDI: 0000000000000003
RBP: 00007fc3030f7296 R08: 0000000000000010 R09: 0000000000000000
R10: 0000000020000200 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fc30323cf80 R15: 00007ffd65b238c8
 </TASK>
rcu: rcu_preempt kthread starved for 9920 jiffies! g32581 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:26816 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 3691 Comm: kworker/u4:5 Not tainted 5.15.168-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xa93/0xd90 kernel/smp.c:969
Code: 04 03 84 c0 0f 85 84 00 00 00 45 8b 7d 00 44 89 fe 83 e6 01 31 ff e8 5c d5 0b 00 41 83 e7 01 75 07 e8 f1 d1 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00
RSP: 0018:ffffc900012ee500 EFLAGS: 00000293
RAX: ffffffff8174a164 RBX: 1ffff110172280b1 RCX: ffff88807a90d940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900012ee640 R08: ffffffff8174a134 R09: ffffed1017227679
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
R13: ffff8880b9140588 R14: ffff8880b903b380 R15: 0000000000000001
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:900 [inline]
 flush_tlb_mm_range+0x2a5/0x4a0 arch/x86/mm/tlb.c:986
 flush_tlb_page arch/x86/include/asm/tlbflush.h:239 [inline]
 ptep_clear_flush+0x112/0x150 mm/pgtable-generic.c:97
 page_mkclean_one+0x428/0x7b0 mm/rmap.c:938
 rmap_walk_file+0x3f8/0x600 mm/rmap.c:2378
 rmap_walk mm/rmap.c:2396 [inline]
 page_mkclean+0x330/0x490 mm/rmap.c:1006
 clear_page_dirty_for_io+0x3ce/0xa60 mm/page-writeback.c:2749
 mpage_submit_page+0x90/0x230 fs/ext4/inode.c:2092
 mpage_process_page_bufs+0x6c8/0x8b0 fs/ext4/inode.c:2226
 mpage_prepare_extent_to_map+0xc9d/0x1150 fs/ext4/inode.c:2654
 ext4_writepages+0xcd0/0x3d10 fs/ext4/inode.c:2782
 do_writepages+0x481/0x730 mm/page-writeback.c:2386
 __writeback_single_inode+0x15b/0xe30 fs/fs-writeback.c:1647
 writeback_sb_inodes+0xbce/0x1a40 fs/fs-writeback.c:1930
 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:2001
 wb_writeback+0x465/0xc50 fs/fs-writeback.c:2106
 wb_check_old_data_flush fs/fs-writeback.c:2206 [inline]
 wb_do_writeback fs/fs-writeback.c:2259 [inline]
 wb_workfn+0xc55/0x1130 fs/fs-writeback.c:2288
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/21 14:05 linux-5.15.y 584a40a22cb9 f1e4447c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sctp_setsockopt
* Struck through repros no longer work on HEAD.