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INFO: rcu detected stall in sys_bpf

Status: upstream: reported syz repro on 2024/04/20 10:27
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+66feb346d5c375250c6e@syzkaller.appspotmail.com
First crash: 716d, last: 23h08m
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/09/07 linux-6.1.y (ToT) 28c695c365e1 syz [report] INFO: rcu detected stall in corrupted
2025/09/07 upstream (ToT) b236920731dd 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 1535d 1628d 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 439d 678d 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 171 1d03h 727d 0/3 upstream: reported C repro on 2024/04/09 19:57
upstream INFO: rcu detected stall in sys_bpf (3) bpf 1 4 2280d 2280d 0/29 closed as invalid on 2020/01/09 08:13
linux-5.15 INFO: rcu detected stall in sys_bpf 1 2 851d 894d 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 2447d 2567d 0/29 auto-closed as invalid on 2019/11/23 00:18
upstream INFO: rcu detected stall in sys_bpf (2) bpf 1 12 2315d 2317d 0/29 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in sys_bpf (8) bpf 1 1 870d 870d 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 2264d 2394d 0/1 auto-closed as invalid on 2020/05/23 14:47
upstream BUG: soft lockup in sys_bpf mm 1 C error 129 13h33m 349d 0/29 upstream: reported C repro on 2025/04/23 05:48
upstream INFO: rcu detected stall in sys_bpf (6) net 1 7 1347d 1497d 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 2233d 2273d 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 62 5h14m 239d 0/2 upstream: reported C repro on 2025/08/10 11:50
android-54 BUG: soft lockup in sys_bpf 1 1 416d 416d 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 571d 738d 0/2 upstream: reported C repro on 2024/03/29 12:25
android-5-10 BUG: soft lockup in sys_bpf 1 2 651d 656d 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 85d 85d 0/2 premoderation: reported on 2026/01/12 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-.... } 2691 jiffies s: 22549 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: 10248 Comm: syz.4.5474 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:asm_sysvec_irq_work+0x0/0x20 arch/x86/include/asm/idtentry.h:722
Code: e9 b5 03 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 b5 02 00 00 48 89 c4 48 89 e7 e8 9a 60 ec ff e9 95 03 00 00 90 90 90 90 90 <0f> 01 ca fc 6a ff e8 95 02 00 00 48 89 c4 48 89 e7 e8 6a 65 ec ff
RSP: 0018:ffffc900001e0738 EFLAGS: 00000006
RAX: 6bb61ffca01a0700 RBX: 1ffff9200003c0f4 RCX: 6bb61ffca01a0700
RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0d20
RBP: ffffc900001e0860 R08: ffffffff90af534f R09: 1ffffffff215ea69
R10: dffffc0000000000 R11: fffffbfff215ea6a R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8f3b900 R15: 0000000000000002
FS:  000055557d15d500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000092 CR3: 000000002f7be000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
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 92 31 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:ffffc900001e0760 EFLAGS: 00000206
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 ndisc_send_skb+0xd9d/0x14e0 net/ipv6/ndisc.c:521
 addrconf_rs_timer+0x2d1/0x630 net/ipv6/addrconf.c:3979
 call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:2023
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036
 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:lock_release+0x5ab/0x920 kernel/locking/lockdep.c:5686
Code: 00 00 00 f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 2f 04 f8 75 70 f7 44 24 50 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 2f 00 00 00 00 43 c7 44 2f 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc900047574a0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: ffffffffffffffff RCX: 6bb61ffca01a0700
RDX: 0000000000000000 RSI: ffffffff8a8c23a0 RDI: ffffffff8adf0d20
RBP: ffffc900047575a8 R08: ffffffff8e1fcc2f R09: 1ffffffff1c3f985
R10: dffffc0000000000 R11: fffffbfff1c3f986 R12: ffff8880261ba8a0
R13: dffffc0000000000 R14: ffff8880261ba890 R15: 1ffff920008eaea0
 prep_new_page mm/page_alloc.c:2566 [inline]
 get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357
 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5643
 __alloc_pages_bulk+0x49a/0x920 mm/page_alloc.c:5591
 vm_area_alloc_pages mm/vmalloc.c:2968 [inline]
 __vmalloc_area_node mm/vmalloc.c:3071 [inline]
 __vmalloc_node_range+0x70f/0x13b0 mm/vmalloc.c:3243
 __vmalloc_node mm/vmalloc.c:3308 [inline]
 __vmalloc+0x76/0x80 mm/vmalloc.c:3322
 bpf_prog_alloc_no_stats+0x3a/0x3a0 kernel/bpf/core.c:92
 bpf_prog_alloc+0x1c/0x1b0 kernel/bpf/core.c:130
 bpf_prog_load+0x7c9/0x1560 kernel/bpf/syscall.c:2597
 __sys_bpf+0x5b8/0x780 kernel/bpf/syscall.c:5030
 __do_sys_bpf kernel/bpf/syscall.c:5134 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5132 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5132
 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: 0033:0x7f8ec3d9bf79
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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe58ead018 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f8ec4015fa0 RCX: 00007f8ec3d9bf79
RDX: 0000000000000094 RSI: 00002000000001c0 RDI: 0000000000000005
RBP: 00007f8ec3e327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8ec4015fac R14: 00007f8ec4015fa0 R15: 00007f8ec4015fa0
 </TASK>

Crashes (113):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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
2026/04/06 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
2026/03/24 11:50 linux-6.1.y f2ddafa93a25 baf8bf12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/24 07:07 linux-6.1.y f2ddafa93a25 baf8bf12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/22 23:03 linux-6.1.y f2ddafa93a25 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/22 19:31 linux-6.1.y f2ddafa93a25 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/22 00:42 linux-6.1.y f2ddafa93a25 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/21 17:43 linux-6.1.y f2ddafa93a25 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/10 10:40 linux-6.1.y f2ddafa93a25 6972f302 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/09 20:47 linux-6.1.y f2ddafa93a25 176bead5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/09 13:00 linux-6.1.y f2ddafa93a25 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/08 21:29 linux-6.1.y f2ddafa93a25 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/05 05:06 linux-6.1.y 2f66dd9cff42 a9fe5c9e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/04 23:01 linux-6.1.y 2f66dd9cff42 e6b6b96b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/03 22:14 linux-6.1.y 779f9571ac3e 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/02 03:14 linux-6.1.y 779f9571ac3e 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/03/01 21:04 linux-6.1.y 779f9571ac3e 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/28 12:03 linux-6.1.y 779f9571ac3e 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/27 09:55 linux-6.1.y 779f9571ac3e a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/26 17:45 linux-6.1.y 779f9571ac3e ffa54287 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/26 08:40 linux-6.1.y 779f9571ac3e e0f78d93 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/23 07:55 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/22 23:25 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/22 20:22 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/22 15:55 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/22 06:19 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/21 20:19 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/19 15:20 linux-6.1.y 8ce36b2849ef 746545b8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/18 02:46 linux-6.1.y 8ce36b2849ef 06ec4f7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/16 07:05 linux-6.1.y 8ce36b2849ef 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/15 23:29 linux-6.1.y 8ce36b2849ef 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/15 14:08 linux-6.1.y 8ce36b2849ef 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/14 11:32 linux-6.1.y 8ce36b2849ef 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/12 04:17 linux-6.1.y 8ce36b2849ef 76a109e2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/10 16:16 linux-6.1.y 0182cb5b74ee 91d776d3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/08 17:18 linux-6.1.y 0182cb5b74ee 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/06 07:54 linux-6.1.y cd9b81672742 f03c4191 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_bpf
2026/02/06 01:48 linux-6.1.y cd9b81672742 f03c4191 .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
2024/07/31 07:20 linux-6.1.y c1cec4dad96b 6fde257d .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.