INFO: rcu detected stall in sys

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-6.1	INFO: rcu detected stall in sendmsg (5)	1	syz			9	24d	182d	0/3	upstream: reported syz repro on 2025/06/23 07:43
linux-6.6	INFO: rcu detected stall in sendmsg	1				4	8d05h	143d	0/2	upstream: reported on 2025/07/31 17:16
upstream	BUG: soft lockup in sys_sendmsg (2) net	1	C			24	18d	200d	0/29	upstream: reported C repro on 2025/06/05 02:15
upstream	INFO: rcu detected stall in sys_sendmsg (2) cgroups mm	1				5	2210d	2211d	0/29	closed as invalid on 2019/12/04 14:14
linux-6.1	INFO: rcu detected stall in sys_sendmsg	1				6	449d	536d	0/3	auto-obsoleted due to no activity on 2025/01/06 11:24
linux-5.15	INFO: rcu detected stall in sys_sendmsg origin:upstream	1	C		error	28	10d	642d	0/3	upstream: reported C repro on 2024/03/19 21:37
upstream	INFO: rcu detected stall in sys_sendmsg net	1	C	done		2	2291d	2291d	13/29	fixed on 2019/10/09 10:54

rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10499 ticks this GP) idle=61e/1/0x4000000000000002 softirq=11301/11301 fqs=126 (t=10501 jiffies g=6825 q=158) rcu: rcu_preempt kthread starved for 10243 jiffies! g6825 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt I28824 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081 schedule+0x181/0x210 kernel/sched/core.c:4155 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline] rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 0 CPU: 0 PID: 8503 Comm: syz-executor.2 Not tainted 5.5.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fb/0x318 lib/dump_stack.c:118 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x15a/0x220 kernel/rcu/tree_stall.h:254 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline] check_cpu_stall kernel/rcu/tree_stall.h:529 [inline] rcu_pending kernel/rcu/tree.c:2827 [inline] rcu_sched_clock_irq+0xe25/0x1ad0 kernel/rcu/tree.c:2271 update_process_times+0x12d/0x180 kernel/time/timer.c:1726 tick_sched_handle kernel/time/tick-sched.c:167 [inline] tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310 __run_hrtimer kernel/time/hrtimer.c:1517 [inline] __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline] smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 </IRQ> RIP: 0010:__sanitizer_cov_trace_pc+0x31/0x50 kernel/kcov.c:192 Code: 0c 25 c0 1d 02 00 65 8b 15 38 5f 8b 7e f7 c2 00 01 1f 00 75 2c 8b 91 80 13 00 00 83 fa 02 75 21 48 8b 91 88 13 00 00 48 8b 32 <48> 8d 7e 01 8b 89 84 13 00 00 48 39 cf 73 08 48 89 44 f2 08 48 89 RSP: 0018:ffffc90002677860 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffffffff814896c6 RBX: ffffea0002348640 RCX: ffff88809019a280 RDX: ffffc9000e442000 RSI: 000000000003ffff RDI: ffffea0002348640 RBP: ffffc90002677888 R08: dffffc0000000000 R09: fffffbfff124248a R10: fffffbfff124248a R11: 0000000000000000 R12: ffff88808d3f51a0 R13: dffffc0000000000 R14: 00000000fffffffc R15: ffff8880937b97f8 free_thread_stack+0x168/0x590 kernel/fork.c:280 release_task_stack kernel/fork.c:440 [inline] put_task_stack+0xa3/0x130 kernel/fork.c:451 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256 context_switch kernel/sched/core.c:3388 [inline] __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081 preempt_schedule_common kernel/sched/core.c:4236 [inline] preempt_schedule+0xdb/0x120 kernel/sched/core.c:4261 ___preempt_schedule+0x16/0x18 arch/x86/entry/thunk_64.S:50 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] _raw_spin_unlock_irqrestore+0xcc/0xe0 kernel/locking/spinlock.c:191 unlock_hrtimer_base kernel/time/hrtimer.c:898 [inline] hrtimer_start_range_ns+0x565/0x690 kernel/time/hrtimer.c:1136 hrtimer_start include/linux/hrtimer.h:421 [inline] j1939_tp_schedule_txtimer+0x7d/0xb0 net/can/j1939/transport.c:671 j1939_sk_send_loop net/can/j1939/socket.c:1047 [inline] j1939_sk_sendmsg+0xdc3/0x15a0 net/can/j1939/socket.c:1160 sock_sendmsg_nosec net/socket.c:639 [inline] sock_sendmsg net/socket.c:659 [inline] ____sys_sendmsg+0x509/0x820 net/socket.c:2330 ___sys_sendmsg net/socket.c:2384 [inline] __sys_sendmsg+0x1ed/0x290 net/socket.c:2417 __do_sys_sendmsg net/socket.c:2426 [inline] __se_sys_sendmsg net/socket.c:2424 [inline] __x64_sys_sendmsg+0x7f/0x90 net/socket.c:2424 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45af49 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fa1d47f0c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045af49 RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa1d47f16d4 R13: 00000000004ca8d3 R14: 00000000004e3c48 R15: 00000000ffffffff