syzbot


INFO: rcu detected stall in sys_perf_event_open (2)

Status: upstream: reported C repro on 2024/09/23 05:55
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+5284a86a0b0a31ab266a@syzkaller.appspotmail.com
First crash: 437d, last: 5d21h
Fix commit to backport (bisect log) :
tree: upstream
commit f4bf3ca2e5cba655824b6e0893a98dfb33ed24e5
Author: Lingutla Chandrasekhar <clingutla@codeaurora.org>
Date: Fri Apr 7 23:05:26 2023 +0000

  softirq: Add trace points for tasklet entry/exit

  
Discussions (2)
Title Replies (including bot) Last reply
Re: [PATCH 6.1] softirq: Add trace points for tasklet entry/exit 3 (3) 2025/08/21 22:05
[PATCH 6.1] softirq: Add trace points for tasklet entry/exit 1 (1) 2025/08/21 18:40
Bug presence (2)
Date Name Commit Repro Result
2025/09/18 linux-6.1.y (ToT) 3db754f56897 C [report] INFO: rcu detected stall in smp_call_function
2025/09/18 upstream (ToT) 86cc796e5e9b C Didn't crash
Similar bugs (16)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in sys_perf_event_open (2) origin:lts-only 1 C error 39 2d20h 694d 0/3 upstream: reported C repro on 2024/01/09 18:19
upstream INFO: rcu detected stall in sys_perf_event_open (3) perf 1 1 2157d 2157d 0/29 closed as invalid on 2020/01/08 05:23
linux-6.6 INFO: rcu detected stall in perf_event_open (2) origin:lts-only 1 C 3 19d 24d 0/2 upstream: reported C repro on 2025/11/10 01:14
upstream INFO: rcu detected stall in sys_perf_event_open (4) perf 1 1 2157d 2156d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in sys_perf_event_open (2) perf 1 8 2192d 2193d 0/29 closed as invalid on 2019/12/04 14:14
linux-6.1 INFO: rcu detected stall in sys_perf_event_open 1 1 541d 541d 0/3 auto-obsoleted due to no activity on 2024/09/19 01:45
linux-6.6 INFO: rcu detected stall in perf_event_open 1 C done 4 98d 111d 2/2 fixed on 2025/10/06 10:09
linux-5.15 INFO: rcu detected stall in sys_perf_event_open 1 1 960d 960d 0/3 auto-obsoleted due to no activity on 2023/08/17 04:33
upstream INFO: rcu detected stall in sys_perf_event_open perf 1 1 2636d 2634d 0/29 auto-closed as invalid on 2019/03/14 17:19
android-5-15 BUG: soft lockup in sys_perf_event_open 1 1 577d 577d 0/2 auto-obsoleted due to no activity on 2024/08/04 07:07
upstream BUG: soft lockup in sys_perf_event_open perf 1 1 552d 548d 0/29 auto-obsoleted due to no activity on 2024/08/29 01:52
upstream BUG: soft lockup in perf_event_open trace bpf 1 2 162d 158d 0/29 auto-obsoleted due to no activity on 2025/09/23 09:29
upstream BUG: soft lockup in sys_perf_event_open (2) kvm fs 1 6 320d 427d 0/29 auto-obsoleted due to no activity on 2025/04/18 04:31
upstream INFO: rcu detected stall in perf_event_open (2) perf 1 1 1528d 1528d 0/29 auto-closed as invalid on 2021/11/26 20:49
upstream INFO: rcu detected stall in perf_event_open kernel 1 1 1625d 1625d 0/29 auto-closed as invalid on 2021/09/21 01:14
upstream INFO: rcu detected stall in __se_sys_perf_event_open perf 1 1 1979d 1979d 0/29 auto-closed as invalid on 2020/10/02 02:08
Last patch testing requests (1)
Created Duration User Patch Repo Result
2025/08/12 15:47 2h08m sumanth.gavini@yahoo.com patch linux-6.1.y OK log
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2024/12/03 12:42 7h31m fix candidate upstream OK (1) job log

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2676 jiffies s: 12257 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11110 Comm: syz.1.3143 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:cpu_max_bits_warn include/linux/cpumask.h:110 [inline]
RIP: 0010:cpumask_check include/linux/cpumask.h:117 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:444 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:1030 [inline]
RIP: 0010:irq_work_queue_on+0x47/0x260 kernel/irq_work.c:134
Code: ff 48 c7 c0 b0 6c 1f 8e 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 a0 01 00 00 44 8b 35 d3 5d 92 0c 89 ef 44 89 f6 e8 d9 c8 f3 ff <44> 39 f5 0f 83 59 01 00 00 e8 6b c7 f3 ff 41 89 ee 89 e8 c1 e8 06
RSP: 0018:ffffc90000007308 EFLAGS: 00000046
RAX: ffffffff818d0ee7 RBX: ffff8880b8e3b9b0 RCX: 0000000000000100
RDX: ffff888078de5940 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffff8880b8e3b9b0
R10: ffffed10171c7738 R11: 1ffff110171c7736 R12: dffffc0000000000
R13: dffffc0000000000 R14: 0000000000000002 R15: 1ffff110171c773a
FS:  00007f35e4dfe6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f063fff CR3: 0000000073280000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_read_unlock_special+0x3c7/0x500 kernel/rcu/tree_plugin.h:678
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 __perf_event_output kernel/events/core.c:7741 [inline]
 perf_event_output_forward+0x237/0x2a0 kernel/events/core.c:7750
 __perf_event_overflow+0x448/0x610 kernel/events/core.c:9496
 perf_tp_event+0x335/0xb60 kernel/events/core.c:10029
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10002
 perf_trace_preemptirq_template+0x287/0x330 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+0x84/0x500 kernel/rcu/tree_plugin.h:685
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 ed 90 96 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc90000007ac0 EFLAGS: 00000206
RAX: 7c98a68c52952500 RBX: 1ffff92000000f60 RCX: 7c98a68c52952500
RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: ffffffff8adef760
RBP: ffffc90000007bc0 R08: dffffc0000000000 R09: fffffbfff215c451
R10: fffffbfff215c451 R11: 1ffffffff215c450 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8e3b900 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 ieee80211_rx_napi+0x219/0x3c0 net/mac80211/rx.c:5330
 ieee80211_rx include/net/mac80211.h:4846 [inline]
 ieee80211_handle_queued_frames+0x105/0x1b0 net/mac80211/main.c:317
 tasklet_action_common+0x298/0x400 kernel/softirq.c:826
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x12f/0x220 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:bytes_is_nonzero mm/kasan/generic.c:84 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x68/0x290 mm/kasan/generic.c:189
Code: c1 eb 03 49 b8 00 00 00 00 00 fc ff df 4f 8d 0c 03 48 8d 5c 37 ff 48 c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 <4d> 85 f6 0f 84 39 01 00 00 48 f7 d3 4c 01 db 41 80 39 00 0f 85 c1
RSP: 0018:ffffc90003b87b60 EFLAGS: 00000283
RAX: ffff888078de5901 RBX: 1ffff1100f1bcdaf RCX: ffffffff81624f70
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888078de6d78
RBP: ffffc90003b87c30 R08: dffffc0000000000 R09: ffffed100f1bcdaf
R10: ffffed100f1bcdb0 R11: 1ffff1100f1bcdaf R12: 0000000000000000
R13: 1ffff92000770f74 R14: 0000000000000001 R15: dffffc0000000001
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 atomic_long_read include/linux/atomic/atomic-instrumented.h:1265 [inline]
 __mutex_trylock_common+0x80/0x250 kernel/locking/mutex.c:107
 __mutex_trylock kernel/locking/mutex.c:152 [inline]
 __mutex_lock_common kernel/locking/mutex.c:606 [inline]
 __mutex_lock+0x13b/0xaf0 kernel/locking/mutex.c:747
 __do_sys_perf_event_open kernel/events/core.c:12796 [inline]
 __se_sys_perf_event_open+0x1af0/0x1e60 kernel/events/core.c:12378
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f35e578f749
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:00007f35e4dfe038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f35e59e5fa0 RCX: 00007f35e578f749
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000480
RBP: 00007f35e5813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f35e59e6038 R14: 00007f35e59e5fa0 R15: 00007ffe37abf138
 </TASK>

Crashes (28):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/28 11:38 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/11/26 08:09 linux-6.1.y f6e38ae624cf 64219f15 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/11/22 14:20 linux-6.1.y f6e38ae624cf 4fb8ef37 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/09/09 04:26 linux-6.1.y 28c695c365e1 d291dd2d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/02/28 09:23 linux-6.1.y 3a8358583626 6a8fcbc4 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_perf_event_open
2024/11/22 03:43 linux-6.1.y b67dc5c9ade9 4b25d554 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_perf_event_open
2025/11/10 11:23 linux-6.1.y f6e38ae624cf 4e1406b4 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/10/18 08:51 linux-6.1.y c2fda4b3f577 1c8c8cd8 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/10/14 22:18 linux-6.1.y 882efbdd9d34 b6605ba8 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/10/06 09:44 linux-6.1.y 882efbdd9d34 49379ee0 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/09/27 10:08 linux-6.1.y 7b34dc04e4ff 001c9061 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/09/14 01:11 linux-6.1.y 3db754f56897 e2beed91 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/08/16 16:05 linux-6.1.y 0bc96de781b4 1804e95e .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/08/10 03:31 linux-6.1.y 3594f306da12 32a0e5ed .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/07/11 06:25 linux-6.1.y dfc486ec9cce 3cda49cf .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/01/12 02:40 linux-6.1.y c63962be84ef 6dbc6a9b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_perf_event_open
2024/09/23 05:54 linux-6.1.y e526b12bf916 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_perf_event_open
2025/11/26 10:22 linux-6.1.y f6e38ae624cf 64219f15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/11/17 14:44 linux-6.1.y f6e38ae624cf ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/11/03 02:47 linux-6.1.y f6e38ae624cf 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/10/26 12:06 linux-6.1.y 8e6e2188d949 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/10/14 14:28 linux-6.1.y 882efbdd9d34 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/10/03 15:05 linux-6.1.y 882efbdd9d34 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/09/22 09:04 linux-6.1.y 363a599da6d9 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/09/21 00:25 linux-6.1.y 363a599da6d9 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/09/19 22:03 linux-6.1.y 363a599da6d9 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/09/02 12:41 linux-6.1.y f89b6e15694c 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
2025/08/10 01:37 linux-6.1.y 3594f306da12 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_event_open
* Struck through repros no longer work on HEAD.