syzbot


BUG: soft lockup in sys_clone3

Status: premoderation: reported on 2026/01/07 17:53
Reported-by: syzbot+70cee6f47601df2a2556@syzkaller.appspotmail.com
First crash: 6d13h, last: 6d13h
Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: rcu detected stall in clone3 origin:lts-only 1 C inconclusive 2 39d 103d 0/2 upstream: reported C repro on 2025/10/02 07:48
upstream INFO: rcu detected stall in sys_clone3 (3) mm 1 26 303d 498d 0/29 auto-obsoleted due to no activity on 2025/06/14 09:25
linux-6.1 INFO: rcu detected stall in sys_clone3 (3) 1 3 417d 476d 0/3 auto-obsoleted due to no activity on 2025/03/02 13:35
upstream INFO: rcu detected stall in sys_clone3 kernfs 1 1 1332d 1332d 0/29 auto-closed as invalid on 2022/08/20 13:01
linux-5.15 INFO: rcu detected stall in sys_clone3 1 1 466d 466d 0/3 auto-obsoleted due to no activity on 2025/01/12 11:21
upstream INFO: rcu detected stall in sys_clone3 (2) mm 1 3 597d 700d 0/29 auto-obsoleted due to no activity on 2024/08/25 02:20
linux-6.1 INFO: rcu detected stall in sys_clone3 1 1 739d 735d 0/3 auto-obsoleted due to no activity on 2024/04/15 06:45
linux-5.15 INFO: rcu detected stall in clone3 1 2 161d 195d 0/3 auto-obsoleted due to no activity on 2025/11/14 02:35
linux-6.1 INFO: rcu detected stall in sys_clone3 (4) 1 1 279d 279d 0/3 auto-obsoleted due to no activity on 2025/07/18 19:29
linux-5.15 INFO: rcu detected stall in sys_clone3 (2) 1 1 333d 333d 0/3 auto-obsoleted due to no activity on 2025/05/25 09:12
linux-6.1 INFO: rcu detected stall in sys_clone3 (2) 1 1 599d 599d 0/3 auto-obsoleted due to no activity on 2024/09/01 21:33

Sample crash report:
RBP: 00007fd708dbe6c0 R08: 00007fd708dbe6c0 R09: 00007ffeb9cf9037
R10: 0000000000000008 R11: 0000000000000206 R12: ffffffffffffffa8
R13: 000000000000006e R14: 00007ffeb9cf8f50 R15: 00007ffeb9cf9038
watchdog: BUG: soft lockup - CPU#0 stuck for 123s! [syz.8.2282:8819]
Modules linked in:
CPU: 0 PID: 8819 Comm: syz.8.2282 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 bf 31 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 95 31
RSP: 0018:ffffc90000cc7970 EFLAGS: 00000a06
RAX: 1ffffffff0c80d33 RBX: ffff888127776010 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000cc79b0 R08: dffffc0000000000 R09: ffffc90000cc75e0
R10: fffff52000198ebf R11: 1ffff92000198ebc R12: ffff8881277763e8
R13: ffff888127776000 R14: ffff888127774010 R15: ffffffff86406998
FS:  000055559396d500(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffdfa50000 CR3: 000000010f993000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 perf_event_task kernel/events/core.c:7804 [inline]
 perf_event_fork+0x142/0x1a0 kernel/events/core.c:7811
 copy_process+0x2ff8/0x32c0 kernel/fork.c:2482
 kernel_clone+0x23f/0x940 kernel/fork.c:2650
 __do_sys_clone3 kernel/fork.c:2934 [inline]
 __se_sys_clone3 kernel/fork.c:2918 [inline]
 __x64_sys_clone3+0x296/0x2f0 kernel/fork.c:2918
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fd70a3abe89
Code: ef 08 00 48 8d 3d 5c ef 08 00 e8 12 29 f6 ff 66 90 b8 ea ff ff ff 48 85 ff 74 2c 48 85 d2 74 27 49 89 c8 b8 b3 01 00 00 0f 05 <48> 85 c0 7c 18 74 01 c3 31 ed 48 83 e4 f0 4c 89 c7 ff d2 48 89 c7
RSP: 002b:00007ffeb9cf8f08 EFLAGS: 00000206 ORIG_RAX: 00000000000001b3
RAX: ffffffffffffffda RBX: 00007fd70a32e2a0 RCX: 00007fd70a3abe89
RDX: 00007fd70a32e2a0 RSI: 0000000000000058 RDI: 00007ffeb9cf8f50
RBP: 00007fd708dbe6c0 R08: 00007fd708dbe6c0 R09: 00007ffeb9cf9037
R10: 0000000000000008 R11: 0000000000000206 R12: ffffffffffffffa8
R13: 000000000000006e R14: 00007ffeb9cf8f50 R15: 00007ffeb9cf9038
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline]
NMI backtrace for cpu 1 skipped: idling at default_idle+0x12/0x20 arch/x86/kernel/process.c:717

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/07 17:52 android13-5.10-lts e253c52bbdfc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10-perf BUG: soft lockup in sys_clone3
* Struck through repros no longer work on HEAD.