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INFO: rcu detected stall in sys_bpf (2)

Status: upstream: reported syz repro on 2024/04/09 19:57
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+4ca114518ed3e3b28ead@syzkaller.appspotmail.com
First crash: 707d, last: 13h32m
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/10/10 linux-5.15.y (ToT) 29e53a5b1c4f syz [report] INFO: rcu detected stall in ktime_get_with_offset
2025/10/10 upstream (ToT) 5472d60c129f syz Didn't crash
▶ ▼ Similar bugs (17)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_bpf (5) bpf 1 C unreliable 56 1515d 1608d 0/29 closed as invalid on 2022/02/08 10:34
upstream INFO: rcu detected stall in sys_bpf (9) bpf net 1 C error 74 419d 658d 0/29 auto-obsoleted due to no activity on 2025/04/03 05:23
upstream INFO: rcu detected stall in sys_bpf (3) bpf 1 4 2260d 2260d 0/29 closed as invalid on 2020/01/09 08:13
linux-5.15 INFO: rcu detected stall in sys_bpf 1 2 831d 874d 0/3 auto-obsoleted due to no activity on 2024/03/16 17:33
upstream INFO: rcu detected stall in sys_bpf net bpf 1 3 2427d 2547d 0/29 auto-closed as invalid on 2019/11/23 00:18
upstream INFO: rcu detected stall in sys_bpf (2) bpf 1 12 2296d 2297d 0/29 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in sys_bpf (8) bpf 1 1 850d 850d 0/29 auto-obsoleted due to no activity on 2024/02/17 03:10
linux-6.1 INFO: rcu detected stall in sys_bpf origin:lts-only 1 syz inconclusive 99 7d23h 696d 0/3 upstream: reported syz repro on 2024/04/20 10:27
linux-4.19 INFO: rcu detected stall in sys_bpf 1 3 2244d 2374d 0/1 auto-closed as invalid on 2020/05/23 14:47
upstream BUG: soft lockup in sys_bpf mm 1 C error 123 2d12h 329d 0/29 upstream: reported C repro on 2025/04/23 05:48
upstream INFO: rcu detected stall in sys_bpf (6) net 1 7 1327d 1477d 0/29 auto-obsoleted due to no activity on 2022/10/28 06:32
upstream INFO: rcu detected stall in sys_bpf (4) bpf net 1 3 2213d 2253d 0/29 auto-closed as invalid on 2020/05/24 13:03
linux-6.6 INFO: rcu detected stall in sys_bpf origin:lts-only 1 C inconclusive 56 17d 219d 0/2 upstream: reported C repro on 2025/08/10 11:50
android-54 BUG: soft lockup in sys_bpf 1 1 396d 396d 0/2 auto-obsoleted due to no activity on 2025/05/15 12:21
android-5-15 BUG: soft lockup in sys_bpf origin:upstream 1 C error 108 551d 718d 0/2 upstream: reported C repro on 2024/03/29 12:25
android-5-10 BUG: soft lockup in sys_bpf 1 2 631d 636d 0/2 auto-obsoleted due to no activity on 2024/09/22 11:37
android-5-10 BUG: soft lockup in sys_bpf (2) 1 1 65d 65d 0/2 premoderation: reported on 2026/01/12 02:06
▶ ▼ Fix bisection attempts (3)
Created Duration User Patch Repo Result
2026/03/10 17:08 35m fix candidate upstream error job log
2026/02/07 20:14 1m fix candidate upstream error job log
2026/01/08 19:12 16m fix candidate upstream error job log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-....: (19 ticks this GP) idle=e35/1/0x4000000000000002 softirq=8827/8827 fqs=2103 
	(detected by 1, t=10506 jiffies, g=10349, q=1536)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4861 Comm: syz.3.147 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:mark_lock+0xd6/0x320 kernel/locking/lockdep.c:4569
Code: eb 24 48 c7 c0 80 3f 0c 96 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 06 02 00 00 83 3d e3 8f af 14 00 74 36 45 31 ff 49 83 c7 50 <4c> 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 a4 82 5f 00
RSP: 0018:ffffc90000006ce0 EFLAGS: 00000086
RAX: 0000000000000fc0 RBX: ffff88802ba59dc0 RCX: ffffffff815caf64
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ffbd0c0
RBP: 0000000000000009 R08: dffffc0000000000 R09: fffffbfff1ff7a19
R10: fffffbfff1ff7a19 R11: 1ffffffff1ff7a18 R12: 0000000000000200
R13: dffffc0000000000 R14: ffff88802ba5a900 R15: ffffffff8f945f90
FS:  00007f28f2e0e6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe88ed23f98 CR3: 0000000079c7c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 mark_usage kernel/locking/lockdep.c:4512 [inline]
 __lock_acquire+0xd5a/0x7c60 kernel/locking/lockdep.c:4966
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 __perf_event_output kernel/events/core.c:7800 [inline]
 perf_event_output_forward+0x9e/0x280 kernel/events/core.c:7822
 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
 perf_swevent_overflow kernel/events/core.c:9591 [inline]
 perf_swevent_event+0x4ad/0x530 kernel/events/core.c:9629
 perf_tp_event+0x32c/0xb50 kernel/events/core.c:10047
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021
 perf_trace_preemptirq_template+0x2be/0x380 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 ad 13 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc900000077a0 EFLAGS: 00000206
RAX: 125d80ca4ace8800 RBX: 1ffff92000000ef8 RCX: 125d80ca4ace8800
RDX: dffffc0000000000 RSI: ffffffff8a0b1820 RDI: ffffffff8a59a4c0
RBP: ffffc90000007880 R08: dffffc0000000000 R09: fffffbfff1ff7a3d
R10: fffffbfff1ff7a3d R11: 1ffffffff1ff7a3c R12: ffffffff8c120b00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:771 [inline]
 ndisc_send_skb+0xdc4/0x14a0 net/ipv6/ndisc.c:521
 addrconf_rs_timer+0x2b8/0x600 net/ipv6/addrconf.c:3956
 call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451
 expire_timers kernel/time/timer.c:1496 [inline]
 __run_timers+0x525/0x7c0 kernel/time/timer.c:1767
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
 handle_softirqs+0x328/0x820 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:kasan_quarantine_put+0x84/0x220 mm/kasan/quarantine.c:234
Code: e8 31 ae c1 ff 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 0f 85 83 00 00 00 41 f7 c7 00 02 00 00 74 01 fb 31 c0 <48> 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f c3 48 8d 80 40 62 03 00 45
RSP: 0018:ffffc9000125f0e0 EFLAGS: 00000206
RAX: 125d80ca4ace8801 RBX: ffff888023360000 RCX: 125d80ca4ace8800
RDX: dffffc0000000000 RSI: ffffffff8a0b1820 RDI: ffffffff8a59a4c0
RBP: ffffc9000125f170 R08: dffffc0000000000 R09: ffffed1017207662
R10: ffffed1017207662 R11: 1ffff11017207661 R12: ffff888016842000
R13: ffff888023360000 R14: 00000000000ae1c0 R15: 0000000000000286
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1710 [inline]
 slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736
 slab_free mm/slub.c:3504 [inline]
 kfree+0xef/0x2a0 mm/slub.c:4564
 free_func_state kernel/bpf/verifier.c:914 [inline]
 free_verifier_state+0xd8/0x220 kernel/bpf/verifier.c:930
 pop_stack+0x3ca/0x550 kernel/bpf/verifier.c:1032
 do_check+0x8c02/0xeac0 kernel/bpf/verifier.c:11482
 do_check_common+0xe67/0x16c0 kernel/bpf/verifier.c:13506
 do_check_main kernel/bpf/verifier.c:13569 [inline]
 bpf_check+0x31f3/0xf090 kernel/bpf/verifier.c:14140
 bpf_prog_load+0x1043/0x1550 kernel/bpf/syscall.c:2354
 __sys_bpf+0x4c2/0x670 kernel/bpf/syscall.c:4657
 __do_sys_bpf kernel/bpf/syscall.c:4761 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4759 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4759
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f28f379eec9
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:00007f28f2e0e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f28f39f5fa0 RCX: 00007f28f379eec9
RDX: 0000000000000048 RSI: 00002000000054c0 RDI: 0000000000000005
RBP: 00007f28f3821f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f28f39f6038 R14: 00007f28f39f5fa0 R15: 00007ffdf8b0b878
 </TASK>

Crashes (154):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/06 04:12 linux-5.15.y 29e53a5b1c4f 49379ee0 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/17 20:27 linux-5.15.y 91d48252ad4b c8810548 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/10 23:33 linux-5.15.y 91d48252ad4b 4683d576 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/09 23:43 linux-5.15.y 91d48252ad4b 176bead5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/02 19:13 linux-5.15.y 3330a8d33e08 b9dd6534 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/02 08:36 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/27 21:28 linux-5.15.y 3330a8d33e08 2cf092b8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/27 08:47 linux-5.15.y 3330a8d33e08 a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/23 05:11 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/23 01:26 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/22 17:42 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/22 05:05 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/21 11:42 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/20 23:38 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/20 02:12 linux-5.15.y 3330a8d33e08 c8d8c52d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/13 00:11 linux-5.15.y e45d5d41c134 504cb1bf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/10 09:35 linux-5.15.y 7b232985052f 4ab09a02 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/09 02:50 linux-5.15.y 7b232985052f 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/08 01:45 linux-5.15.y 7b232985052f 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/07 04:53 linux-5.15.y 7b232985052f f20fc9f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/06 09:54 linux-5.15.y 9eec9a14ee10 f03c4191 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/05 08:28 linux-5.15.y 9eec9a14ee10 ea10c935 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/03 06:23 linux-5.15.y 9eec9a14ee10 d78927dd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/03 03:12 linux-5.15.y 9eec9a14ee10 d78927dd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/30 02:55 linux-5.15.y 9eec9a14ee10 bfa73b7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/23 14:57 linux-5.15.y 9eec9a14ee10 e2b1b6e6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/22 22:04 linux-5.15.y 9eec9a14ee10 82c9c083 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/17 13:15 linux-5.15.y 68efe5a6c16a 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/16 13:28 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/16 11:25 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/15 07:47 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/13 22:24 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/09 08:52 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/09 06:10 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/07 20:35 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/06 00:32 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/05 15:04 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/04 22:27 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/04 18:57 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/03 14:13 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/01 07:24 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/01 02:42 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2025/12/30 07:56 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2025/12/28 08:34 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2025/12/17 15:40 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2025/12/17 03:00 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_bpf
2025/11/20 06:01 linux-5.15.y cc5ec8769306 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_bpf
2024/04/09 19:57 linux-5.15.y 9465fef4ae35 171ec371 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_bpf
* Struck through repros no longer work on HEAD.