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INFO: rcu detected stall in fq_pie_timer

Status: auto-obsoleted due to no activity on 2024/10/31 18:20
Reported-by: syzbot+d7d5aab0ec13e6e303c5@syzkaller.appspotmail.com
First crash: 898d, last: 807d
Fix commit to backport (bisect log) :
tree: upstream
commit f85fa45d4a9408d98c46c8fa45ba2e3b2f4bf219
Author: Peilin Ye <peilin.ye@bytedance.com>
Date: Mon May 29 19:54:03 2023 +0000

  net/sched: Reserve TC_H_INGRESS (TC_H_CLSACT) for ingress (clsact) Qdiscs

  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2024/10/31 upstream (ToT) 0fc810ae3ae1 syz Didn't crash
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in fq_pie_timer (2) net 1 C done inconclusive 38 257d 679d 0/29 auto-obsoleted due to no activity on 2025/06/02 03:26
upstream INFO: rcu detected stall in fq_pie_timer net 1 C error 35 1379d 1596d 20/29 fixed on 2022/03/08 16:11
upstream BUG: soft lockup in fq_pie_timer (2) net 1 C error done 3 925d 991d 0/29 closed as invalid on 2023/05/26 05:46
upstream BUG: soft lockup in fq_pie_timer net 1 C error error 10 1121d 1158d 0/29 closed as invalid on 2022/11/18 11:06
linux-6.1 BUG: soft lockup in fq_pie_timer (2) origin:upstream 1 C inconclusive 5 565d 800d 0/3 upstream: reported C repro on 2023/08/29 01:49
upstream BUG: soft lockup in fq_pie_timer (4) net 1 syz 5 785d 836d 23/29 fixed on 2023/10/12 12:48
linux-6.1 BUG: soft lockup in fq_pie_timer 1 C done 7 879d 887d 3/3 fixed on 2023/07/22 07:09
▶ ▼ Fix bisection attempts (2)
Created Duration User Patch Repo Result
2023/12/03 15:21 6h40m fix candidate upstream OK (1) job log
2023/10/02 20:05 3h23m fix candidate upstream error job log

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10500 ticks this GP) idle=581/1/0x4000000000000000 softirq=8229/8229 fqs=4931 
	(t=10500 jiffies g=10597 q=999)
NMI backtrace for cpu 0
CPU: 0 PID: 14 Comm: ksoftirqd/0 Not tainted 5.15.127-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb 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_dump_cpu_stacks+0x223/0x390 kernel/rcu/tree_stall.h:343
 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:711 [inline]
 rcu_pending kernel/rcu/tree.c:3911 [inline]
 rcu_sched_clock_irq+0xf26/0x1770 kernel/rcu/tree.c:2606
 update_process_times+0x196/0x200 kernel/time/timer.c:1788
 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:1685 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 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
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:pie_calculate_probability+0x447/0x820
Code: 20 48 8b 5c 24 30 74 08 48 89 df e8 b3 f5 5f f9 48 c7 03 00 00 00 00 eb 11 e8 35 55 16 f9 eb 05 e8 2e 55 16 f9 4c 8b 6c 24 20 <0f> b6 6c 24 07 40 22 6c 24 06 31 ff 48 8b 5c 24 48 48 89 de e8 f0
RSP: 0018:ffffc90000d37930 EFLAGS: 00000246
RAX: 1ffff920022e78d8 RBX: ffffc9001173c6c0 RCX: ffff88813fe21dc0
RDX: 0000000000000101 RSI: 0000000000000000 RDI: fffffff0a3da8872
RBP: ffffc9001173c6c0 R08: ffffffff8869be70 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffffc9001173c6a8
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000
 fq_pie_timer+0x132/0x260 net/sched/sch_fq_pie.c:389
 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1466 [inline]
 __run_timers+0x67c/0x890 kernel/time/timer.c:1737
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1750
 __do_softirq+0x3b3/0x93a kernel/softirq.c:558
 run_ksoftirqd+0xc1/0x120 kernel/softirq.c:921
 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>

Crashes (23):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/20 04:47 linux-5.15.y f6f7927ac664 d216d8a0 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in fq_pie_timer
2023/08/15 00:24 linux-5.15.y 24c4de4069cb 39990d51 .config console log report syz [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in fq_pie_timer
2023/07/29 03:36 linux-5.15.y 09996673e313 92476829 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in fq_pie_timer
2023/05/22 23:26 linux-5.15.y 9d6bde853685 4bce1a3e .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in fq_pie_timer
2023/07/17 00:15 linux-5.15.y d54cfc420586 35d9ecc5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in fq_pie_timer
2023/06/09 17:26 linux-5.15.y 7349e40704a0 9018a337 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in fq_pie_timer
2023/08/21 11:22 linux-5.15.y f6f7927ac664 d216d8a0 .config console log report syz [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/08/18 05:34 linux-5.15.y f6f7927ac664 74b106b6 .config console log report syz [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/08/16 03:18 linux-5.15.y 24c4de4069cb 39990d51 .config console log report syz [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/08/16 00:01 linux-5.15.y 24c4de4069cb 39990d51 .config console log report syz [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/08/06 21:24 linux-5.15.y 38d4ca22a528 4ffcc9ef .config console log report syz [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/06/28 00:47 linux-5.15.y f67653019430 4cd5bb25 .config console log report syz [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/06/07 08:58 linux-5.15.y d7af3e5ba454 a4ae4f42 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/06/06 15:09 linux-5.15.y d7af3e5ba454 a4ae4f42 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/06/08 08:29 linux-5.15.y d7af3e5ba454 058b3a5a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan BUG: soft lockup in fq_pie_timer
2023/06/14 02:32 linux-5.15.y 7349e40704a0 d2ee9228 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/06/14 01:57 linux-5.15.y 7349e40704a0 d2ee9228 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/06/13 18:00 linux-5.15.y 7349e40704a0 749afb64 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/06/09 20:59 linux-5.15.y 7349e40704a0 9018a337 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/06/09 15:26 linux-5.15.y 7349e40704a0 9018a337 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/06/06 09:15 linux-5.15.y d7af3e5ba454 a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/06/05 19:37 linux-5.15.y d7af3e5ba454 a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
2023/06/03 18:37 linux-5.15.y 0ab06468cbd1 a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in fq_pie_timer
* Struck through repros no longer work on HEAD.