syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=e41/1/0x4000000000000002 softirq=7378/7379 fqs=10 
	(detected by 1, t=10506 jiffies, g=8477, q=504)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 14 Comm: ksoftirqd/0 Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:preempt_count_add+0x30/0x180 kernel/sched/core.c:5482
Code: fb 48 c7 c0 c0 ff a8 96 48 c1 e8 03 49 bf 00 00 00 00 00 fc ff df 42 0f b6 04 38 84 c0 0f 85 e2 00 00 00 83 3d 60 74 51 15 00 <75> 07 65 8b 05 5f e4 aa 7e 65 01 1d 58 e4 aa 7e 48 c7 c0 c0 ff a8
RSP: 0018:ffffc90000007fb8 EFLAGS: 00000046
RAX: 0000000000000004 RBX: 0000000000010000 RCX: ffffffff96a8ff03
RDX: 0000000000000100 RSI: ffffffff8aa59780 RDI: 0000000000010000
RBP: 0000000000000000 R08: ffffffff81870605 R09: fffffbfff1c14c0e
R10: 0000000000000000 R11: ffffc90000007ff8 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efd2dccaac0 CR3: 0000000021ead000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 irq_enter_rcu+0x19/0xe0 kernel/softirq.c:600
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0x90/0xc0 arch/x86/kernel/irq_work.c:17
 </IRQ>
 <TASK>
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x84/0x520 kernel/rcu/tree_plugin.h:671
Code: f1 f1 f1 00 f2 f2 f2 49 89 04 17 66 41 c7 44 17 09 f3 f3 41 c6 44 17 0b f3 65 44 8b 25 6d 82 96 7e 41 f7 c4 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 3a 00 00 00 00 66 42 c7 44 3a
RSP: 0018:ffffc90000d37640 EFLAGS: 00000206
RAX: 10e1f281cef78e00 RBX: 1ffff920001a6ed0 RCX: ffffffff81633db8
RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: ffffffff8af9f000
RBP: ffffc90000d37718 R08: dffffc0000000000 R09: fffffbfff2131241
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff8cb23d00
R13: ffff88813ff22218 R14: ffffc90000d37680 R15: 1ffff920001a6ecc
 __rcu_read_unlock+0x92/0x100 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:771 [inline]
 ndisc_send_skb+0xc9c/0x13c0 net/ipv6/ndisc.c:519
 addrconf_rs_timer+0x357/0x610 net/ipv6/addrconf.c:3959
 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1451
 expire_timers kernel/time/timer.c:1496 [inline]
 __run_timers+0x67c/0x890 kernel/time/timer.c:1767
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
 run_ksoftirqd+0xc6/0x120 kernel/softirq.c:925
 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread starved for 10455 jiffies! g8477 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:25688 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 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:
NMI backtrace for cpu 1
CPU: 1 PID: 4515 Comm: syz.0.66 Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:unwind_next_frame+0x41b/0x1fa0 arch/x86/kernel/unwind_orc.c:461
Code: 0f b6 04 10 84 c0 0f 85 c5 14 00 00 c6 03 01 49 c7 c6 e0 96 a8 8a 49 8d 6e 04 49 8d 5e 05 49 89 ec 49 c1 ec 03 41 0f b6 04 14 <84> c0 0f 85 33 14 00 00 48 89 d8 48 c1 e8 03 0f b6 04 10 84 c0 0f
RSP: 0018:ffffc90000dd0188 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: ffffffff8f108acd RCX: ffffffff8e780e8c
RDX: dffffc0000000000 RSI: ffffffff8f108abc RDI: ffffffff8e780e80
RBP: ffffffff8f108acc R08: 0000000000000008 R09: ffffc90000dd0330
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff1e21159
R13: ffffffff8a3efd2c R14: ffffffff8f108ac8 R15: ffffc90000dd0240
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kfree+0xf1/0x270 mm/slub.c:4559
 skb_free_head net/core/skbuff.c:655 [inline]
 skb_release_data+0x73a/0x8a0 net/core/skbuff.c:677
 skb_release_all net/core/skbuff.c:742 [inline]
 __kfree_skb net/core/skbuff.c:756 [inline]
 kfree_skb_reason+0xb3/0x170 net/core/skbuff.c:776
 kfree_skb include/linux/skbuff.h:1118 [inline]
 ip6_mc_input+0x97a/0xb80 net/ipv6/ip6_input.c:572
 NF_HOOK+0x364/0x410 include/linux/netfilter.h:302
 __netif_receive_skb_one_core net/core/dev.c:5493 [inline]
 __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5607
 process_backlog+0x363/0x7f0 net/core/dev.c:6484
 __napi_poll+0xc7/0x440 net/core/dev.c:7043
 napi_poll net/core/dev.c:7110 [inline]
 net_rx_action+0x617/0xda0 net/core/dev.c:7200
 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
 __do_softirq kernel/softirq.c:592 [inline]
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653
 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:zap_pte_range mm/memory.c:1351 [inline]
RIP: 0010:zap_pmd_range mm/memory.c:1505 [inline]
RIP: 0010:zap_pud_range mm/memory.c:1534 [inline]
RIP: 0010:zap_p4d_range mm/memory.c:1555 [inline]
RIP: 0010:unmap_page_range+0x1d4a/0x2630 mm/memory.c:1576
Code: 64 24 08 e9 3b f7 ff ff 89 d9 80 e1 07 80 c1 03 38 c1 7c 9e 48 89 df e8 24 bc 11 00 eb 94 e8 0d e0 c7 ff 4c 8b 64 24 58 eb 08 <e8> 01 e0 c7 ff 4d 89 ef 48 8b bc 24 d0 00 00 00 48 8d b4 24 c0 01
RSP: 0018:ffffc90003407420 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 0000000000000008 RCX: ffff88801f073b80
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000000
RBP: ffffc90003407650 R08: ffffffff81b89235 R09: ffffed1003e0e771
R10: 0000000000000000 R11: dffffc0000000001 R12: 00007f86e91e8000
R13: dffffc0000000000 R14: 1ffff11003de41e8 R15: 8000000066d3a007
 unmap_vmas+0x1f8/0x390 mm/memory.c:1653
 exit_mmap+0x3b6/0x620 mm/mmap.c:3204
 __mmput+0x112/0x3b0 kernel/fork.c:1127
 exit_mm+0x688/0x7f0 kernel/exit.c:550
 do_exit+0x626/0x2480 kernel/exit.c:861
 do_group_exit+0x144/0x310 kernel/exit.c:996
 get_signal+0xc66/0x14e0 kernel/signal.c:2900
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f86eab33d29
Code: Unable to access opcode bytes at RIP 0x7f86eab33cff.
RSP: 002b:00007f86e89a4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: 0000000000000005 RBX: 00007f86ead23fa0 RCX: 00007f86eab33d29
RDX: 0000000000000005 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 00007f86eabafb08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f86ead23fa0 R15: 00007ffec9f2d8e8
 </TASK>