rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-....: (0 ticks this GP) idle=b2d/1/0x4000000000000002 softirq=27296/27296 fqs=5242 (detected by 1, t=10502 jiffies, g=34561, q=1184) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11230 Comm: syz.3.1789 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:strlen+0x3f/0x60 lib/string.c:581 Code: fc ff df 48 89 fb 49 89 c7 48 89 d8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 11 48 ff c3 49 8d 47 01 42 80 7c 3f 01 00 75 de eb 19 <89> d9 80 e1 07 38 c1 7c e6 49 89 fc 48 89 df e8 8d 6a b7 fd 4c 89 RSP: 0018:ffffc90000007438 EFLAGS: 00000006 RAX: 0000000000000006 RBX: ffffffff8a2c2bcb RCX: 000000008a2c2b02 RDX: 0000000000000000 RSI: ffffffff8c31eaa0 RDI: ffffffff8a2c2bc0 RBP: ffffc90000007560 R08: 0000000000000002 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1b13c6e R12: dffffc0000000000 R13: 1ffff92000000e94 R14: dffffc0000000000 R15: 000000000000000a FS: 00007f31bb0d26c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f70e22c64ac CR3: 000000007b660000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: trace_event_get_offsets_lock_acquire include/trace/events/lock.h:13 [inline] perf_trace_lock_acquire+0xc6/0x3e0 include/trace/events/lock.h:13 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x3d7/0x400 kernel/locking/lockdep.c:5594 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313 rcu_read_lock include/linux/rcupdate.h:740 [inline] __perf_output_begin kernel/events/ring_buffer.c:163 [inline] perf_output_begin_forward+0xa5/0xa40 kernel/events/ring_buffer.c:271 __perf_event_output kernel/events/core.c:7804 [inline] perf_event_output_forward+0x19b/0x2e0 kernel/events/core.c:7822 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515 perf_tp_event+0x383/0xbf0 kernel/events/core.c:10047 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021 perf_trace_preemptirq_template+0x2aa/0x360 include/trace/events/preemptirq.h:14 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:ffs arch/x86/include/asm/bitops.h:297 [inline] RIP: 0010:handle_softirqs+0x1a9/0x830 kernel/softirq.c:564 Code: 24 78 44 89 64 24 28 0f b7 db 48 c7 c7 80 0f 2a 8a e8 5b 38 73 08 65 66 c7 05 61 57 ba 7e 00 00 e8 2c 0b 36 00 fb 89 5c 24 34 ff ff ff ff 0f bc 44 24 34 41 89 c5 41 ff c5 0f 85 d2 00 00 00 RSP: 0018:ffffc90000007e20 EFLAGS: 00000282 RAX: 1b17600da03e4b00 RBX: 0000000000000200 RCX: 1b17600da03e4b00 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980 RBP: ffffc90000007f30 R08: ffffffff901d40cf R09: 1ffffffff203a819 R10: dffffc0000000000 R11: fffffbfff203a81a R12: 000000000000000a R13: 0000000000000000 R14: ffff88802ca15940 R15: dffffc0000000000 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:rcu_read_unlock_special+0x0/0x4a0 kernel/rcu/tree_plugin.h:625 Code: 46 af 58 00 eb b0 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 94 49 89 fd 4c 89 f7 e8 2c af 58 00 4c 89 ef eb 84 0f 1f 80 00 00 00 00 <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec a0 00 RSP: 0018:ffffc90002f2f728 EFLAGS: 00000206 RAX: 0000000000000000 RBX: ffff88802ca15d7c RCX: 0000000000080000 RDX: ffffc90006029000 RSI: 000000000007ffff RDI: ffff88802ca15940 RBP: ffffc90002f2f870 R08: dffffc0000000000 R09: 1ffffffff203a818 R10: dffffc0000000000 R11: fffffbfff203a819 R12: 1ffff11005942baf R13: dffffc0000000000 R14: ffff88802ca15d80 R15: dffffc0000000000 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:772 [inline] inet_twsk_purge+0x7a2/0x840 net/ipv4/inet_timewait_sock.c:309 ops_exit_list net/core/net_namespace.c:177 [inline] setup_net+0x844/0xa10 net/core/net_namespace.c:365 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:503 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 copy_namespaces+0x37d/0x3e0 kernel/nsproxy.c:178 copy_process+0x1834/0x3e20 kernel/fork.c:2293 kernel_clone+0x23f/0x990 kernel/fork.c:2679 __do_sys_clone kernel/fork.c:2796 [inline] __se_sys_clone kernel/fork.c:2780 [inline] __x64_sys_clone+0x19a/0x210 kernel/fork.c:2780 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f31bce78819 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:00007f31bb0d1fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f31bd0f1fa0 RCX: 00007f31bce78819 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000010eb22f000 RBP: 00007f31bcf0ec91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f31bd0f2038 R14: 00007f31bd0f1fa0 R15: 00007ffe60b05098