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INFO: rcu detected stall in sys_bpf

Status: upstream: reported C repro on 2024/04/20 10:27
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+66feb346d5c375250c6e@syzkaller.appspotmail.com
First crash: 767d, last: 21h32m
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2026/05/06 linux-6.1.y (ToT) 4931e0e1673d C [report] INFO: rcu detected stall in sys_epoll_wait
2026/05/06 upstream (ToT) 74fe02ce122a C 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 1586d 1678d 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 489d 729d 0/29 auto-obsoleted due to no activity on 2025/04/03 05:23
linux-5.15 INFO: rcu detected stall in sys_bpf (2) origin:lts-only 1 C error 208 2d10h 777d 0/3 upstream: reported C repro on 2024/04/09 19:57
upstream INFO: rcu detected stall in sys_bpf (3) bpf 1 4 2331d 2331d 0/29 closed as invalid on 2020/01/09 08:13
linux-5.15 INFO: rcu detected stall in sys_bpf 1 2 902d 944d 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 2497d 2617d 0/29 auto-closed as invalid on 2019/11/23 00:18
upstream INFO: rcu detected stall in sys_bpf (2) bpf 1 12 2366d 2367d 0/29 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in sys_bpf (8) bpf 1 1 920d 920d 0/29 auto-obsoleted due to no activity on 2024/02/17 03:10
linux-4.19 INFO: rcu detected stall in sys_bpf 1 3 2315d 2444d 0/1 auto-closed as invalid on 2020/05/23 14:47
upstream BUG: soft lockup in sys_bpf mm prio:low 1 C error 168 8h13m 399d 0/29 upstream: reported C repro on 2025/04/23 05:48
upstream INFO: rcu detected stall in sys_bpf (6) net 1 7 1397d 1547d 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 2284d 2323d 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 69 2d08h 290d 0/2 upstream: reported C repro on 2025/08/10 11:50
android-54 BUG: soft lockup in sys_bpf 1 1 467d 467d 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 622d 789d 0/2 upstream: reported C repro on 2024/03/29 12:25
android-5-10 BUG: soft lockup in sys_bpf 1 2 702d 706d 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 135d 135d 0/2 auto-obsoleted due to no activity on 2026/04/12 02:06
▶ ▼ Fix bisection attempts (1)
Created Duration User Patch Repo Result
2025/11/09 17:26 2h10m fix candidate upstream OK (0) job log

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2641 jiffies s: 1141 root: 0x2/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4393 Comm: syz-executor766 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:interrupt_context_level include/linux/preempt.h:95 [inline]
RIP: 0010:get_recursion_context kernel/events/internal.h:214 [inline]
RIP: 0010:perf_swevent_get_recursion_context+0x67/0x150 kernel/events/core.c:9755
Code: dd 80 39 65 8c 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 38 eb 2d 00 4c 8b 33 65 8b 05 e6 d8 5c 7e 89 c3 48 89 de <48> 81 e6 00 00 f0 00 40 0f 95 c5 31 ff e8 b7 e2 dc ff 48 89 de 48
RSP: 0018:ffffc900001e0890 EFLAGS: 00000046
RAX: 0000000000000102 RBX: 0000000000000102 RCX: ffff88801a76d940
RDX: 0000000000000100 RSI: 0000000000000102 RDI: 0000000000000008
RBP: 0000000000000001 R08: ffff8880b8f3580b R09: 1ffff110171e6b01
R10: dffffc0000000000 R11: ffffed10171e6b02 R12: ffffffff8cb7fc20
R13: dffffc0000000000 R14: ffff8880b8f00000 R15: dffffc0000000000
FS:  00005555727dc480(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f432445f0f0 CR3: 000000007333f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 perf_trace_buf_alloc+0x54/0x300 kernel/trace/trace_event_perf.c:414
 perf_trace_preemptirq_template+0x143/0x320 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x7f/0x510 kernel/rcu/tree_plugin.h:685
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 d2 33 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc900001e0ac0 EFLAGS: 00000206
RAX: eaf5a238148b8f00 RBX: 1ffff9200003c160 RCX: eaf5a238148b8f00
RDX: dffffc0000000000 RSI: ffffffff8a8c1120 RDI: ffffffff8adf1320
RBP: ffffc900001e0bb0 R08: ffff8880b8f3580b R09: 1ffff110171e6b01
R10: dffffc0000000000 R11: ffffed10171e6b02 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8f3b900 R15: 0000000000000002
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x156/0x170 net/mac80211/util.c:826
 mac80211_hwsim_beacon+0xb7/0x1b0 drivers/net/wireless/mac80211_hwsim.c:2147
 __run_hrtimer kernel/time/hrtimer.c:1747 [inline]
 __hrtimer_run_queues+0x54a/0xd50 kernel/time/hrtimer.c:1811
 hrtimer_run_softirq+0x183/0x2a0 kernel/time/hrtimer.c:1828
 handle_softirqs+0x2a1/0x930 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 2f ed 20 f7 65 8b 05 80 70 ca 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc900043e6f20 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: eaf5a238148b8f00
RDX: dffffc0000000000 RSI: ffffffff8a8c1120 RDI: 0000000000000001
RBP: ffffc900043e6fb0 R08: ffff8880b8f3580b R09: 1ffff110171e6b01
R10: dffffc0000000000 R11: ffffed10171e6b02 R12: dffffc0000000000
R13: ffff8880618cf000 R14: ffffffff96ed12b0 R15: 1ffff9200087cde4
 __debug_check_no_obj_freed lib/debugobjects.c:988 [inline]
 debug_check_no_obj_freed+0x515/0x530 lib/debugobjects.c:1009
 slab_free_hook mm/slub.c:1704 [inline]
 slab_free_freelist_hook+0xd2/0x1a0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700
 free_func_state kernel/bpf/verifier.c:1094 [inline]
 free_verifier_state+0xd8/0x220 kernel/bpf/verifier.c:1110
 do_check_common+0xbca8/0xc6d0 kernel/bpf/verifier.c:14949
 do_check_main kernel/bpf/verifier.c:15006 [inline]
 bpf_check+0xb08f/0x10db0 kernel/bpf/verifier.c:15583
 bpf_prog_load+0x101a/0x1560 kernel/bpf/syscall.c:2651
 __sys_bpf+0x5b8/0x780 kernel/bpf/syscall.c:5031
 __do_sys_bpf kernel/bpf/syscall.c:5135 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5133 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5133
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f43243b7e19
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 d0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffd4e99308 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f43243b7e19
RDX: 0000000000000090 RSI: 0000200000000780 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007fffd4e99338
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fffd4e99338
R13: 00007fffd4e99350 R14: 00007fffd4e99390 R15: 0000000000000007
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.327 msecs

Crashes (151):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/01 22:45 linux-6.1.y 4931e0e1673d 753c55b9 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/14 14:14 linux-6.1.y 8ce36b2849ef 1e62d198 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/01/19 07:28 linux-6.1.y cd9b81672742 20d37d28 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2025/09/03 14:50 linux-6.1.y f89b6e15694c 96a211bc .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/26 20:19 linux-6.1.y dcbcab9d7079 a3e47276 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/24 10:14 linux-6.1.y dcbcab9d7079 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/23 08:23 linux-6.1.y c27210688955 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/21 06:32 linux-6.1.y c27210688955 41b8c833 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/17 23:44 linux-6.1.y c27210688955 de5aae85 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/14 10:55 linux-6.1.y ad16b162f21d 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/14 08:59 linux-6.1.y ad16b162f21d 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/11 13:05 linux-6.1.y ad16b162f21d 845acb1c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/08 10:29 linux-6.1.y 4931e0e1673d 5633175a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/07 17:33 linux-6.1.y 4931e0e1673d cbf9e0fc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/03 23:07 linux-6.1.y 4931e0e1673d a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/03 21:33 linux-6.1.y 4931e0e1673d a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/03 04:49 linux-6.1.y 4931e0e1673d a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/02 20:41 linux-6.1.y 4931e0e1673d a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/02 12:16 linux-6.1.y 4931e0e1673d a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/01 00:11 linux-6.1.y 4931e0e1673d a7464baf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/27 16:37 linux-6.1.y 7c87defbd336 0f700595 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/26 05:27 linux-6.1.y 7c87defbd336 9c2d0995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/26 03:22 linux-6.1.y 7c87defbd336 9c2d0995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/25 21:45 linux-6.1.y 7c87defbd336 9c2d0995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/25 19:12 linux-6.1.y 7c87defbd336 9c2d0995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/25 16:13 linux-6.1.y 7c87defbd336 9c2d0995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/24 19:55 linux-6.1.y 7c87defbd336 1c2b9291 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/23 04:15 linux-6.1.y 7c87defbd336 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/19 23:50 linux-6.1.y 7c87defbd336 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/19 13:41 linux-6.1.y 7c87defbd336 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/17 22:47 linux-6.1.y 8e8fc038cad5 24ecfc1e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/16 05:41 linux-6.1.y 8e8fc038cad5 df15c5f3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/15 21:25 linux-6.1.y 8e8fc038cad5 c441f497 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/13 13:47 linux-6.1.y 8e8fc038cad5 9530ccf9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/11 23:23 linux-6.1.y 8e8fc038cad5 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/10 16:27 linux-6.1.y 1989cd3d56e2 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/09 23:34 linux-6.1.y 1989cd3d56e2 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/08 23:16 linux-6.1.y 1989cd3d56e2 d9b7f621 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/06 09:38 linux-6.1.y 1989cd3d56e2 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/05 22:41 linux-6.1.y 1989cd3d56e2 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/05 10:04 linux-6.1.y 1989cd3d56e2 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/05 02:17 linux-6.1.y 1989cd3d56e2 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/04 10:21 linux-6.1.y 1989cd3d56e2 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/04 03:05 linux-6.1.y 1989cd3d56e2 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/04/01 15:00 linux-6.1.y 1989cd3d56e2 9a1f7828 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/26 05:27 linux-6.1.y 1989cd3d56e2 c6143aac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2025/05/02 02:01 linux-6.1.y 535ec20c5027 51b137cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_bpf
2024/04/20 10:26 linux-6.1.y 6741e066ec76 af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/05/24 22:07 linux-6.1.y dcbcab9d7079 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 INFO: rcu detected stall in sys_bpf
* Struck through repros no longer work on HEAD.