rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6397/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=15281, q=252 ncpus=2)
task:syz.2.112 state:R running task stack:24256 pid:6397 tgid:6396 ppid:5851 task_flags:0x400140 flags:0x00080000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1539/0x5080 kernel/sched/core.c:6907
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:kallsyms_expand_symbol kernel/kallsyms.c:-1 [inline]
RIP: 0010:kallsyms_lookup_names+0x35e/0x1620 kernel/kallsyms.c:186
Code: 7f 0f b6 43 01 c1 e0 07 41 09 c6 48 83 c3 02 49 89 df 31 ff 44 89 f6 e8 70 85 0b 00 45 85 f6 0f 84 f1 02 00 00 b8 00 02 00 00 <48> 89 44 24 20 c7 44 24 30 00 00 00 00 48 8d 9c 24 a0 00 00 00 4c
RSP: 0018:ffffc9000bc7eb80 EFLAGS: 00000202
RAX: 0000000000000200 RBX: ffffffff8d59b0bf RCX: 0000000000000002
RDX: ffff88807ffc5ac0 RSI: 000000000000000d RDI: 0000000000000000
RBP: ffffc9000bc7eea8 R08: ffffc9000bc7ee1f R09: 0000000000000000
R10: ffffc9000bc7ec20 R11: fffff5200178fdc4 R12: 0000000000000098
R13: 00000000000000b8 R14: 000000000000000d R15: ffffffff8d59b0c0
kallsyms_lookup_name+0x6c/0x210 kernel/kallsyms.c:236
__find_trim+0x2d5/0x480 net/core/dev.c:13391
trim_netdev_trace+0x358/0x3d0 net/core/dev.c:13432
save_netdev_trace_buffer+0x115/0x610 net/core/dev.c:13453
__dev_hold include/linux/netdevice.h:4403 [inline]
netdev_hold include/linux/netdevice.h:4446 [inline]
ipv4_blackhole_route+0x108/0x690 net/ipv4/route.c:2906
make_blackhole net/xfrm/xfrm_policy.c:3157 [inline]
xfrm_lookup_route+0xd7/0x1c0 net/xfrm/xfrm_policy.c:3352
udp_sendmsg+0x154a/0x22f0 net/ipv4/udp.c:1451
sock_sendmsg_nosec+0x128/0x1d0 net/socket.c:737
__sock_sendmsg net/socket.c:752 [inline]
____sys_sendmsg+0x589/0x8c0 net/socket.c:2610
___sys_sendmsg+0x2a5/0x360 net/socket.c:2664
__sys_sendmmsg+0x27c/0x4e0 net/socket.c:2753
__do_sys_sendmmsg net/socket.c:2780 [inline]
__se_sys_sendmmsg net/socket.c:2777 [inline]
__x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2777
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6de939aeb9
RSP: 002b:00007f6dea276028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f6de9615fa0 RCX: 00007f6de939aeb9
RDX: 0000000000000300 RSI: 0000200000004d00 RDI: 0000000000000003
RBP: 00007f6de9408c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000f00 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6de9616038 R14: 00007f6de9615fa0 R15: 00007fff9cf76a78
</TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g15281 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=6665
rcu: rcu_preempt kthread starved for 10502 jiffies! g15281 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:I stack:28088 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1539/0x5080 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6401 Comm: syz.4.113 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026
RIP: 0010:num_possible_cpus include/linux/cpumask.h:1222 [inline]
RIP: 0010:mm_get_cid kernel/sched/sched.h:3835 [inline]
RIP: 0010:sched_mm_cid_fork+0x2f6/0xc20 kernel/sched/core.c:10631
Code: 01 00 00 85 ed 0f 84 0b 01 00 00 31 ed 31 db e9 c1 01 00 00 49 c7 c5 98 7e 19 8e 49 c1 ed 03 eb 07 44 89 e0 f7 d8 71 8d f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c0 75 50 44 8b
RSP: 0000:ffffc9000bbafc78 EFLAGS: 00000887
RAX: 0000000080000000 RBX: 0000000000000002 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff88802b4579d0
RBP: ffff88802b4579d0 R08: 1ffff1100568ade9 R09: ffff88802b457094
R10: ffff88802b456f50 R11: fffff52001775f80 R12: 0000000080000000
R13: 1ffffffff1c32fd3 R14: 0000000000000002 R15: ffff88802b456e40
FS: 00007f4d33ce96c0(0000) GS:ffff8881252af000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000197030 CR3: 000000007a9b6000 CR4: 00000000003526f0
Call Trace:
<TASK>
bprm_execve+0xda1/0x1410 fs/exec.c:1771
do_execveat_common+0x50d/0x690 fs/exec.c:1846
__do_sys_execveat fs/exec.c:1941 [inline]
__se_sys_execveat fs/exec.c:1934 [inline]
__x64_sys_execveat+0xc7/0xf0 fs/exec.c:1934
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4d32d9aeb9
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:00007f4d33ce9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000142
RAX: ffffffffffffffda RBX: 00007f4d33015fa0 RCX: 00007f4d32d9aeb9
RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000004
RBP: 00007f4d32e08c1f R08: 0000000000001000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4d33016038 R14: 00007f4d33015fa0 R15: 00007fff5c1ebfc8
</TASK>