syzbot


BUG: soft lockup in sys_exit_group (2)

Status: premoderation: reported on 2026/01/29 20:38
Reported-by: syzbot+1d8879b6280912a76649@syzkaller.appspotmail.com
First crash: 17h00m, last: 17h00m
Similar bugs (12)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 BUG: soft lockup in sys_exit_group 1 1 558d 558d 0/2 auto-obsoleted due to no activity on 2024/10/19 10:22
android-5-15 BUG: soft lockup in sys_exit_group 1 C error 7 519d 662d 0/2 auto-obsoleted due to no activity on 2024/12/07 01:30
upstream BUG: soft lockup in sys_exit_group usb 1 C 6 2141d 2163d 15/29 fixed on 2020/04/15 17:19
upstream INFO: rcu detected stall in sys_exit_group (7) net 1 C unreliable inconclusive 90 571d 1567d 0/29 upstream: reported C repro on 2021/10/15 18:41
linux-5.15 INFO: rcu detected stall in sys_exit_group (2) 1 3 652d 687d 0/3 auto-obsoleted due to no activity on 2024/07/27 04:53
linux-6.1 INFO: rcu detected stall in sys_exit_group (3) origin:upstream 1 C error 22 1d05h 738d 0/3 upstream: reported C repro on 2024/01/23 11:05
linux-6.1 INFO: rcu detected stall in sys_exit_group (2) 1 1 884d 884d 0/3 auto-obsoleted due to no activity on 2023/12/07 20:57
linux-6.1 INFO: rcu detected stall in sys_exit_group 1 1 995d 995d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:06
linux-5.15 INFO: rcu detected stall in sys_exit_group 1 1 946d 946d 0/3 auto-obsoleted due to no activity on 2023/10/06 21:30
linux-6.6 INFO: rcu detected stall in sys_exit_group origin:upstream 1 C 10 23d 192d 0/2 upstream: reported C repro on 2025/07/21 16:02
linux-5.15 INFO: rcu detected stall in sys_exit_group (3) 1 2 441d 475d 0/3 auto-obsoleted due to no activity on 2025/02/22 19:05
linux-5.15 INFO: rcu detected stall in sys_exit_group (4) origin:upstream 1 C error 5 37d 133d 0/3 upstream: reported C repro on 2025/09/19 02:54

Sample crash report:
RBP: 00007ffd04110adc R08: 0000000000000000 R09: 00000000000927c0
R10: 0000000000000006 R11: 0000000000000246 R12: 00000000000000cc
R13: 00000000000927c0 R14: 000000000010387a R15: 00007ffd04110b30
watchdog: BUG: soft lockup - CPU#0 stuck for 123s! [syz.3.16448:24778]
Modules linked in:
CPU: 0 PID: 24778 Comm: syz.3.16448 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__pmu_filter_match kernel/events/core.c:2309 [inline]
RIP: 0010:pmu_filter_match kernel/events/core.c:2326 [inline]
RIP: 0010:event_filter_match kernel/events/core.c:2337 [inline]
RIP: 0010:perf_iterate_sb_cpu kernel/events/core.c:7526 [inline]
RIP: 0010:perf_iterate_sb+0x583/0xd50 kernel/events/core.c:7558
Code: 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 ff e8 9f 82 1c 00 4d 8b 3f b8 18 01 00 00 49 01 c7 4c 89 f8 48 c1 e8 03 <48> b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 ff e8 75 82
RSP: 0018:ffffc9000135f930 EFLAGS: 00000a02
RAX: 1ffffffff0cc0d13 RBX: ffff888116f03810 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000135f970 R08: ffffc9000135f5b7 R09: ffffc9000135f5a0
R10: dffffc0000000000 R11: fffff5200026beb7 R12: ffff888116f03be8
R13: ffff888116f03800 R14: ffff888116f07810 R15: ffffffff86606898
FS:  0000555555a9a500(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f32d442bd58 CR3: 000000013c199000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 8000000000000000
DR3: 8000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 perf_event_task kernel/events/core.c:7804 [inline]
 perf_event_exit_task+0x147c/0x14e0 kernel/events/core.c:12660
 do_exit+0x5d1/0x2500 kernel/exit.c:857
 do_group_exit+0x141/0x310 kernel/exit.c:986
 __do_sys_exit_group kernel/exit.c:997 [inline]
 __se_sys_exit_group kernel/exit.c:995 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:995
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f232a289eb9
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:00007ffd04110a78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f232a289eb9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffd04110adc R08: 0000000000000000 R09: 00000000000927c0
R10: 0000000000000006 R11: 0000000000000246 R12: 00000000000000cc
R13: 00000000000927c0 R14: 000000000010387a R15: 00007ffd04110b30
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 18832 Comm: kworker/u4:2 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:229 [inline]
RIP: 0010:smp_call_function_single+0x209/0x490 kernel/smp.c:517
Code: 48 44 89 f6 83 e6 01 31 ff e8 13 88 0a 00 41 83 e6 01 49 bc 00 00 00 00 00 fc ff df 75 0a e8 4e 84 0a 00 e9 a4 00 00 00 f3 90 <f7> 44 24 48 01 00 00 00 0f 84 8f 00 00 00 e8 34 84 0a 00 eb e9 e8
RSP: 0018:ffffc90000d17720 EFLAGS: 00000293
RAX: ffffffff815a319c RBX: 0000000000000000 RCX: ffff88810d434f00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000d17810 R08: ffff8881f7057647 R09: 1ffff1103ee0aec8
R10: dffffc0000000000 R11: ffffed103ee0aec9 R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff920001a2ee8
FS:  0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffca9c44b7c CR3: 000000000640f000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000200000000300
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 smp_call_function_many_cond+0x90a/0xa00 kernel/smp.c:653
 smp_call_function_many kernel/smp.c:716 [inline]
 smp_call_function kernel/smp.c:738 [inline]
 on_each_cpu+0xab/0x180 kernel/smp.c:837
 text_poke_sync arch/x86/kernel/alternative.c:1568 [inline]
 text_poke_bp_batch+0x1cb/0x5f0 arch/x86/kernel/alternative.c:1768
 text_poke_flush arch/x86/kernel/alternative.c:1959 [inline]
 text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:1966
 arch_jump_label_transform_apply+0x15/0x30 arch/x86/kernel/jump_label.c:126
 __jump_label_update+0x37c/0x3a0 kernel/jump_label.c:459
 jump_label_update+0x34c/0x3e0 kernel/jump_label.c:825
 static_key_enable_cpuslocked+0x126/0x240 kernel/jump_label.c:177
 static_key_enable+0x1a/0x30 kernel/jump_label.c:190
 toggle_allocation_gate+0xba/0x440 mm/kfence/core.c:624
 process_one_work+0x6e1/0xba0 kernel/workqueue.c:2301
 worker_thread+0xa6a/0x13c0 kernel/workqueue.c:2447
 kthread+0x346/0x3d0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/29 20:37 android13-5.10-lts 186f761c519d aeb6fdd5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10-perf BUG: soft lockup in sys_exit_group
* Struck through repros no longer work on HEAD.