rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-....: (1 GPs behind) idle=5c1/1/0x4000000000000002 softirq=13721/13725 fqs=2112 
	(detected by 1, t=10505 jiffies, g=16997, q=1814)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6299 Comm: syz.0.601 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:65
Code: 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa <4c> 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01
RSP: 0018:ffffc90000006d80 EFLAGS: 00000002
RAX: 0000000000000000 RBX: ffffc90000006e80 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90000006ee0
RBP: dffffc0000000000 R08: ffffc90000006edf R09: ffffc90000006ed0
R10: dffffc0000000000 R11: fffff52000000ddc R12: 1ffffffff1c0b17d
R13: 1ffffffff1c0b17d R14: ffffc90000006eb5 R15: ffffffff8e058bec
FS:  00007f17ef7a56c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000005d903000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 unwind_next_frame+0x9e3/0x1cf0 arch/x86/kernel/unwind_orc.c:547
 perf_callchain_kernel+0x470/0x760 arch/x86/events/core.c:2783
 get_perf_callchain+0x356/0x460 kernel/events/callchain.c:200
 perf_callchain kernel/events/core.c:7606 [inline]
 perf_prepare_sample+0x352/0x1cb0 kernel/events/core.c:7633
 __perf_event_output kernel/events/core.c:7802 [inline]
 perf_event_output_forward+0x185/0x2e0 kernel/events/core.c:7822
 __perf_event_overflow+0x35f/0x550 kernel/events/core.c:9515
 perf_tp_event+0x324/0xbe0 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:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 f2 1f 9d 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc90000007780 EFLAGS: 00000206
RAX: 7cf3aab397741900 RBX: 1ffff92000000ef4 RCX: 7cf3aab397741900
RDX: dffffc0000000000 RSI: ffffffff8a2b2be0 RDI: ffffffff8a7a42c0
RBP: ffffc90000007860 R08: ffffffff901ef1c7 R09: 1ffffffff203de38
R10: dffffc0000000000 R11: fffffbfff203de39 R12: ffffffff8c323400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 ndisc_send_skb+0xd3b/0x1410 net/ipv6/ndisc.c:521
 addrconf_rs_timer+0x367/0x640 net/ipv6/addrconf.c:3966
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x56c/0x810 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x336/0x830 kernel/softirq.c:576
 __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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:finish_lock_switch+0x12f/0x290 kernel/sched/core.c:4804
Code: 83 c7 18 be ff ff ff ff e8 0e fb 6b 08 85 c0 74 46 4d 85 ff 75 62 0f 1f 44 00 00 48 89 df e8 c8 6a 75 08 e8 33 dd 2a 00 fb 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 2f 0e fe ff 43 80 3c 2c
RSP: 0018:ffffc900033beed8 EFLAGS: 00000286
RAX: 7cf3aab397741900 RBX: ffff88802798d940 RCX: 7cf3aab397741900
RDX: dffffc0000000000 RSI: ffffffff8a2b2be0 RDI: ffffffff8a7a42c0
RBP: 1ffff11017207613 R08: ffffffff901ef0f7 R09: 1ffffffff203de1e
R10: dffffc0000000000 R11: fffffbfff203de1f R12: 1ffff110172075c1
R13: dffffc0000000000 R14: ffff8880b903ae08 R15: 0000000000000000
 finish_task_switch+0x12f/0x650 kernel/sched/core.c:4921
 context_switch kernel/sched/core.c:5052 [inline]
 __schedule+0x11cb/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 rwsem_down_read_slowpath+0x53e/0x9b0 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x96/0x2e0 kernel/locking/rwsem.c:1500
 mmap_read_lock+0x1c/0x50 include/linux/mmap_lock.h:117
 do_user_addr_fault+0xc3f/0xc90 arch/x86/mm/fault.c:1306
 handle_page_fault arch/x86/mm/fault.c:1443 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0010:copy_user_enhanced_fast_string+0xe/0x40 arch/x86/lib/copy_user_64.S:206
Code: 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 90 90 90 90 90 90 90 0f 01 cb 83 fa 40 0f 82 70 ff ff ff 89 d1 <f3> a4 31 c0 0f 01 ca c3 90 90 90 90 90 90 90 90 90 90 89 d1 83 f8
RSP: 0018:ffffc900033bf4b8 EFLAGS: 00050202
RAX: ffffffff83e64c01 RBX: 0000000000000ec0 RCX: 0000000000000b80
RDX: 0000000000000ec0 RSI: ffff88807420e340 RDI: 00002000000b4000
RBP: ffffc900033bf608 R08: ffff88807420eebf R09: 1ffff1100e841dd7
R10: dffffc0000000000 R11: ffffed100e841dd8 R12: ffff88807420e000
R13: 0000000000000eff R14: 00002000000b3cc0 R15: 00000000000b2700
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline]
 copyout lib/iov_iter.c:157 [inline]
 _copy_to_iter+0x322/0x1170 lib/iov_iter.c:670
 __skb_datagram_iter+0xde/0x740 net/core/datagram.c:425
 skb_copy_datagram_iter+0xad/0x1f0 net/core/datagram.c:541
 skb_copy_datagram_msg include/linux/skbuff.h:3773 [inline]
 unix_stream_read_actor+0x68/0xa0 net/unix/af_unix.c:2829
 unix_stream_read_generic+0xd1c/0x2180 net/unix/af_unix.c:2748
 unix_stream_recvmsg+0x16f/0x1d0 net/unix/af_unix.c:2867
 ____sys_recvmsg+0x2ca/0x5b0 net/socket.c:-1
 ___sys_recvmsg+0x213/0x5c0 net/socket.c:2707
 __sys_recvmsg net/socket.c:2737 [inline]
 __do_sys_recvmsg net/socket.c:2747 [inline]
 __se_sys_recvmsg net/socket.c:2744 [inline]
 __x64_sys_recvmsg+0x201/0x2d0 net/socket.c:2744
 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: 0033:0x7f17f154d0d9
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:00007f17ef7a5028 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007f17f17d4fa0 RCX: 00007f17f154d0d9
RDX: 0000000040000100 RSI: 0000200000001140 RDI: 0000000000000007
RBP: 00007f17f15e4024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f17f17d5038 R14: 00007f17f17d4fa0 R15: 00007ffd5ec8f9f8
 </TASK>