rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 ticks this GP) idle=3eb/1/0x4000000000000002 softirq=56678/56678 fqs=0 
	(detected by 1, t=10503 jiffies, g=79169, q=1791)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 20071 Comm: kworker/0:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:match_held_lock+0x0/0xb0 kernel/locking/lockdep.c:5070
Code: db 85 c0 74 d8 83 3d 36 55 cd 03 00 75 cf 48 c7 c7 a0 26 2b 8a 48 c7 c6 e0 26 2b 8a e8 b9 0a f5 ff 0f 0b eb b6 e8 f0 fa ff ff <b9> 01 00 00 00 48 39 77 10 74 6c 53 81 7f 20 00 00 10 00 72 5f 48
RSP: 0018:ffffc90000006e90 EFLAGS: 00000083
RAX: 0000000000000009 RBX: ffff88805ac15940 RCX: 0000000000000000
RDX: 0000000000000100 RSI: ffffffff8c31eb20 RDI: ffff88805ac16520
RBP: 00000000ffffffff R08: ffffc90000006f97 R09: ffffc90000006f80
R10: dffffc0000000000 R11: fffff52000000df3 R12: 0000000000000006
R13: 0000000000000046 R14: ffffffff8c31eb20 R15: ffff88805ac16520
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcc9fde9fc0 CR3: 000000000c08e000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000200000000300
DR3: 0000200000000300 DR6: 00000000ffff0ff1 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __lock_is_held kernel/locking/lockdep.c:5366 [inline]
 lock_is_held_type+0xa6/0x190 kernel/locking/lockdep.c:5666
 __perf_output_begin kernel/events/ring_buffer.c:170 [inline]
 perf_output_begin_forward+0x1af/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_swevent_overflow kernel/events/core.c:9591 [inline]
 perf_swevent_event+0x4ad/0x530 kernel/events/core.c:9629
 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: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 32 e1 9c 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:ffffc900000076a0 EFLAGS: 00000206
RAX: 92a6024246a1fe00 RBX: 1ffff92000000ed8 RCX: 92a6024246a1fe00
RDX: dffffc0000000000 RSI: ffffffff8a2b2800 RDI: ffffffff8a79fe00
RBP: ffffc90000007770 R08: ffffffff901d515f R09: 1ffffffff203aa2b
R10: dffffc0000000000 R11: fffffbfff203aa2c R12: ffffffff8c323000
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock+0x85/0x90 include/linux/rcupdate.h:772
 icmp6_send+0x134b/0x1990 net/ipv6/icmp.c:633
 __icmpv6_send include/linux/icmpv6.h:28 [inline]
 icmpv6_send include/linux/icmpv6.h:49 [inline]
 ip6_link_failure+0x35/0x490 net/ipv6/route.c:2789
 dst_link_failure include/net/dst.h:422 [inline]
 ndisc_error_report+0x10e/0x150 net/ipv6/ndisc.c:717
 neigh_invalidate+0x22c/0x440 net/core/neighbour.c:1001
 neigh_timer_handler+0x910/0xfe0 net/core/neighbour.c:1088
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x339/0x830 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:crng_make_state+0x516/0x670 drivers/char/random.c:393
Code: 87 73 05 e9 2b fd ff ff e8 37 84 26 fd e8 52 19 6a 05 4d 85 f6 0f 84 f8 fe ff ff e8 24 84 26 fd fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 04 2f 00 00 00 00 4b c7 44 2f 08 00 00 00 00 4b c7 44 2f 10
RSP: 0018:ffffc900033df8a0 EFLAGS: 00000293
RAX: ffffffff8452b06c RBX: 0000000000000000 RCX: ffff88805ac15940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900033df9f0 R08: ffffffff901d51bf R09: 1ffffffff203aa37
R10: dffffc0000000000 R11: fffffbfff203aa38 R12: ffff8880b9037248
R13: dffffc0000000000 R14: 0000000000000200 R15: 1ffff9200067bf1c
 _get_random_bytes+0xfc/0x250 drivers/char/random.c:405
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:691 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:721 [inline]
 nsim_dev_trap_report_work+0x686/0xb40 drivers/net/netdevsim/dev.c:762
 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10502 jiffies! g79169 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=47250
rcu: rcu_preempt kthread starved for 10503 jiffies! g79169 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:27600 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
 rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x9b/0x370 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 20071 Comm: kworker/0:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline]
RIP: 0010:kasan_check_range+0x10/0x290 mm/kasan/generic.c:189
Code: b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 ac 01 00 00 55 41 57 41 56 <41> 54 53 49 89 f8 49 01 f0 0f 82 0e 02 00 00 49 89 f8 49 c1 e8 2f
RSP: 0018:ffffc90000006b00 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000015 RCX: ffffffff815d26ae
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff901d50c0
RBP: ffffc90000006d70 R08: dffffc0000000000 R09: 1ffffffff203aa18
R10: dffffc0000000000 R11: fffffbfff203aa19 R12: 00000000ec63f067
R13: ffff88805ac15940 R14: 0000000041bead14 R15: ffff88805ac16590
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcc9fde9fc0 CR3: 000000000c08e000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000200000000300
DR3: 0000200000000300 DR6: 00000000ffff0ff1 DR7: 0000000000000600
Call Trace:
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 hlock_class kernel/locking/lockdep.c:197 [inline]
 __lock_acquire+0x10be/0x7d10 kernel/locking/lockdep.c:5008
 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
 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_swevent_overflow kernel/events/core.c:9591 [inline]
 perf_swevent_event+0x4ad/0x530 kernel/events/core.c:9629
 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: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 32 e1 9c 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:ffffc900000076a0 EFLAGS: 00000206
RAX: 92a6024246a1fe00 RBX: 1ffff92000000ed8 RCX: 92a6024246a1fe00
RDX: dffffc0000000000 RSI: ffffffff8a2b2800 RDI: ffffffff8a79fe00
RBP: ffffc90000007770 R08: ffffffff901d515f R09: 1ffffffff203aa2b
R10: dffffc0000000000 R11: fffffbfff203aa2c R12: ffffffff8c323000
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock+0x85/0x90 include/linux/rcupdate.h:772
 icmp6_send+0x134b/0x1990 net/ipv6/icmp.c:633
 __icmpv6_send include/linux/icmpv6.h:28 [inline]
 icmpv6_send include/linux/icmpv6.h:49 [inline]
 ip6_link_failure+0x35/0x490 net/ipv6/route.c:2789
 dst_link_failure include/net/dst.h:422 [inline]
 ndisc_error_report+0x10e/0x150 net/ipv6/ndisc.c:717
 neigh_invalidate+0x22c/0x440 net/core/neighbour.c:1001
 neigh_timer_handler+0x910/0xfe0 net/core/neighbour.c:1088
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x339/0x830 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:crng_make_state+0x516/0x670 drivers/char/random.c:393
Code: 87 73 05 e9 2b fd ff ff e8 37 84 26 fd e8 52 19 6a 05 4d 85 f6 0f 84 f8 fe ff ff e8 24 84 26 fd fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 04 2f 00 00 00 00 4b c7 44 2f 08 00 00 00 00 4b c7 44 2f 10
RSP: 0018:ffffc900033df8a0 EFLAGS: 00000293
RAX: ffffffff8452b06c RBX: 0000000000000000 RCX: ffff88805ac15940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900033df9f0 R08: ffffffff901d51bf R09: 1ffffffff203aa37
R10: dffffc0000000000 R11: fffffbfff203aa38 R12: ffff8880b9037248
R13: dffffc0000000000 R14: 0000000000000200 R15: 1ffff9200067bf1c
 _get_random_bytes+0xfc/0x250 drivers/char/random.c:405
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:691 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:721 [inline]
 nsim_dev_trap_report_work+0x686/0xb40 drivers/net/netdevsim/dev.c:762
 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>