rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4380/1:b..l
	(detected by 0, t=10502 jiffies, g=7649, q=96)
task:syz.3.53        state:R  running task     stack:23768 pid: 4380 ppid:  4167 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5029 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6375
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6779
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 0c ac 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc900030af580 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92000615ebc RCX: 1ffff92000615e5c
RDX: dffffc0000000000 RSI: ffffffff8aab3d00 RDI: ffffffff8af9fa80
RBP: ffffc900030af6e0 R08: dffffc0000000000 R09: fffffbfff2131e19
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000615eb8
R13: dffffc0000000000 R14: ffffc900030af5e0 R15: 0000000000000246
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 inet_twsk_purge+0x129/0x9e0 net/ipv4/inet_timewait_sock.c:268
 ops_exit_list net/core/net_namespace.c:177 [inline]
 setup_net+0x8cf/0xad0 net/core/net_namespace.c:365
 copy_net_ns+0x392/0x5d0 net/core/net_namespace.c:486
 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
 copy_namespaces+0x365/0x3b0 kernel/nsproxy.c:178
 copy_process+0x1841/0x3ef0 kernel/fork.c:2208
 kernel_clone+0x210/0x960 kernel/fork.c:2603
 __do_sys_clone kernel/fork.c:2720 [inline]
 __se_sys_clone kernel/fork.c:2704 [inline]
 __x64_sys_clone+0x237/0x2a0 kernel/fork.c:2704
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fed19563169
RSP: 002b:00007fed173cbfe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fed1977bfa0 RCX: 00007fed19563169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000640c7000
RBP: 00007fed195e42a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fed1977bfa0 R15: 00007ffda3e09f88
 </TASK>
rcu: rcu_preempt kthread starved for 10538 jiffies! g7649 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:R  running task     stack:26168 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5029 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6375
 schedule+0x11b/0x1f0 kernel/sched/core.c:6458
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4455 Comm: syz.0.82 Not tainted 5.15.179-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:clear_bhb_loop+0x66/0x70 arch/x86/entry/entry_64.S:1556
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc b8 05 00 00 00 eb 01 90 83 e8 01 75 f8 83 e9 01 75 ae c3 0f ae e8 <5d> c3 cc cc cc cc cc cc cc cc 0f 01 f8 50 58 65 48 8b 24 25 d0 6f
RSP: 0018:ffffc9000314ff48 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000000000000000f RDI: ffffc9000314ff58
RBP: ffffc9000314ff48 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f893c2956c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2ce023 CR3: 00000000762f2000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 </TASK>