| Date | Name | Commit | Repro | Result |
|---|---|---|---|---|
| 2025/08/27 | linux-6.1.y (ToT) | 0bc96de781b4 | C | [report] INFO: rcu detected stall in perf_event_open |
| 2025/08/27 | upstream (ToT) | 39f90c196721 | C | Didn't crash |
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| Date | Name | Commit | Repro | Result |
|---|---|---|---|---|
| 2025/08/27 | linux-6.1.y (ToT) | 0bc96de781b4 | C | [report] INFO: rcu detected stall in perf_event_open |
| 2025/08/27 | upstream (ToT) | 39f90c196721 | C | Didn't crash |
| Created | Duration | User | Patch | Repo | Result |
|---|---|---|---|---|---|
| 2025/11/13 01:20 | 11h02m | fix candidate | upstream | OK (1) job log | |
| 2025/06/27 04:15 | 2h09m | fix candidate | upstream | OK (0) job log | |
| 2025/06/06 18:47 | 2h16m | bisect fix | linux-6.1.y | OK (0) job log log | |
| 2025/04/07 14:34 | 2h31m | bisect fix | linux-6.1.y | OK (0) job log log |
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2648 jiffies s: 2461 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: 4489 Comm: syz.3.46 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:__kasan_check_read+0x2/0x10 mm/kasan/shadow.c:31
Code: 41 5d 41 5e 41 5f 5d c3 48 c7 c7 c8 cc 60 8c eb 0a 48 c7 c7 47 64 45 8c 48 89 de e8 78 0c 4f 08 31 ed eb d7 00 00 cc cc 89 f6 <48> 8b 0c 24 31 d2 e9 a3 ec ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01
RSP: 0018:ffffc90000006c58 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 000000000000002c RCX: 0000000000080000
RDX: 000000000000002c RSI: 0000000000000008 RDI: ffffffff90af7240
RBP: ffffc90000006eb0 R08: dffffc0000000000 R09: 0000000000000001
R10: dffffc0000000000 R11: fffffbfff1c3fbde R12: ffff888024793b80
R13: 0000000000000000 R14: 0000000000000000 R15: 000000000000002c
FS: 000055557950a500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000004 CR3: 00000000184aa000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
instrument_atomic_read include/linux/instrumented.h:72 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
hlock_class kernel/locking/lockdep.c:228 [inline]
check_wait_context kernel/locking/lockdep.c:4723 [inline]
__lock_acquire+0x541/0x7d10 kernel/locking/lockdep.c:4999
lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
__perf_event_output kernel/events/core.c:7728 [inline]
perf_event_output_forward+0xdf/0x2f0 kernel/events/core.c:7750
__perf_event_overflow+0x448/0x610 kernel/events/core.c:9496
perf_swevent_overflow+0x19b/0x230 kernel/events/core.c:9579
perf_swevent_event+0x458/0x570 kernel/events/core.c:-1
perf_tp_event+0x3e7/0xc30 kernel/events/core.c:10064
perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10032
perf_trace_preemptirq_template+0x268/0x320 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:ffffc90000007760 EFLAGS: 00000206
RAX: 3e170d3d7829a900 RBX: 1ffff92000000ef4 RCX: 3e170d3d7829a900
RDX: dffffc0000000000 RSI: ffffffff8a8c10a0 RDI: ffffffff8adf0d20
RBP: ffffc90000007860 R08: ffffffff90af734f R09: 1ffffffff215ee69
R10: dffffc0000000000 R11: fffffbfff215ee6a 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]
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:__syscall_enter_from_user_work kernel/entry/common.c:97 [inline]
RIP: 0010:syscall_enter_from_user_mode+0x2a/0x80 kernel/entry/common.c:118
Code: 41 56 53 48 89 f3 49 89 fe 48 8b 7c 24 10 e8 ed fa ff ff 66 90 66 90 e8 84 13 5b f7 e8 ff 11 5b f7 fb 65 48 8b 05 96 a3 d4 75 <48> 8b 70 08 40 f6 c6 3f 74 0b 4c 89 f7 5b 41 5e e9 b1 6f 41 f7 48
RSP: 0018:ffffc90003617f08 EFLAGS: 00000286
RAX: ffff888024793b80 RBX: 0000000000000003 RCX: 3e170d3d7829a900
RDX: dffffc0000000000 RSI: ffffffff8a8c10a0 RDI: ffffffff8adf0d20
RBP: ffffc90003617f48 R08: ffff8880b8e3580b R09: 1ffff110171c6b01
R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 0000000000000000
R13: 0000000000000000 R14: ffffc90003617f58 R15: 0000000000000000
do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:72
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f853059c819
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:00007fff95d4d118 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00007f8530815fa0 RCX: 00007f853059c819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffffffffff
RBP: 00007f8530632c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8530815fac R14: 00007f8530815fa0 R15: 00007f8530815fa0
</TASK>
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026/04/01 17:03 | linux-6.1.y | 1989cd3d56e2 | 9a1f7828 | .config | console log | report | syz / log | C | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-perf | INFO: rcu detected stall in syscall_enter_from_user_mode | |
| 2026/03/21 21:33 | linux-6.1.y | f2ddafa93a25 | 5b92003d | .config | console log | report | syz / log | C | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-perf | INFO: rcu detected stall in syscall_enter_from_user_mode | |
| 2025/11/29 05:36 | 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 syscall_enter_from_user_mode | |
| 2025/08/20 21:50 | linux-6.1.y | 0bc96de781b4 | 0b9605c8 | .config | console log | report | syz / log | C | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-perf | INFO: rcu detected stall in syscall_enter_from_user_mode | |
| 2026/01/18 00:54 | 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 syscall_enter_from_user_mode | ||
| 2025/10/16 18:59 | linux-6.1.y | c2fda4b3f577 | 19568248 | .config | console log | report | syz / log | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-perf | INFO: rcu detected stall in syscall_enter_from_user_mode | ||
| 2025/02/27 13:21 | 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 syscall_enter_from_user_mode | ||
| 2026/02/19 02:49 | linux-6.1.y | 8ce36b2849ef | 77d4d919 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-perf | INFO: rcu detected stall in syscall_enter_from_user_mode | ||
| 2026/01/30 06:19 | linux-6.1.y | cd9b81672742 | bfa73b7b | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-perf | INFO: rcu detected stall in syscall_enter_from_user_mode | ||
| 2025/11/15 11:47 | linux-6.1.y | f6e38ae624cf | f7988ea4 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-perf | INFO: rcu detected stall in syscall_enter_from_user_mode | ||
| 2025/11/11 14:28 | linux-6.1.y | f6e38ae624cf | 4e1406b4 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-perf | INFO: rcu detected stall in syscall_enter_from_user_mode | ||
| 2025/09/21 21:32 | 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 syscall_enter_from_user_mode | ||
| 2025/08/15 07:02 | linux-6.1.y | 3594f306da12 | 1804e95e | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan | INFO: rcu detected stall in syscall_enter_from_user_mode |