rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10499 ticks this GP) idle=40b/1/0x4000000000000000 softirq=6313/6313 fqs=5 (t=10501 jiffies g=6293 q=8 ncpus=2) rcu: rcu_preempt kthread timer wakeup didn't happen for 10491 jiffies! g6293 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=6232 rcu: rcu_preempt kthread starved for 10494 jiffies! g6293 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:29264 pid: 16 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5106 [inline] __schedule+0xa9a/0x4cc0 kernel/sched/core.c:6421 schedule+0xd2/0x1f0 kernel/sched/core.c:6493 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1907 rcu_gp_fqs_loop+0x1c0/0x840 kernel/rcu/tree.c:2078 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2267 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 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: 3822 Comm: syz-executor.4 Not tainted 5.18.0-rc3-next-20220422-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:kvm_wait+0x98/0x100 arch/x86/kernel/kvm.c:1058 Code: fa 83 e2 07 38 d0 7f 04 84 c0 75 63 0f b6 07 40 38 c6 74 35 48 83 c4 10 c3 c3 e8 23 91 4b 00 eb 07 0f 00 2d da b1 94 08 fb f4 <48> 83 c4 10 c3 89 74 24 0c 48 89 3c 24 e8 56 8f 4b 00 8b 74 24 0c RSP: 0018:ffffc90000de0a20 EFLAGS: 00000246 RAX: 0000000000000007 RBX: 0000000000000000 RCX: 1ffffffff1b73199 RDX: 0000000000000000 RSI: ffffffff81807171 RDI: ffffffff8134dffd RBP: ffffffff8cbfc980 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff81807158 R11: 0000000000000080 R12: 0000000000000000 R13: fffffbfff197f930 R14: 0000000000000001 R15: ffff8880b9d3ae40 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d527000 CR3: 000000000ba8e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pv_wait arch/x86/include/asm/paravirt.h:603 [inline] pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline] __pv_queued_spin_lock_slowpath+0x8c7/0xb50 kernel/locking/qspinlock.c:511 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:85 [inline] do_raw_spin_lock+0x200/0x2a0 kernel/locking/spinlock_debug.c:115 spin_lock include/linux/spinlock.h:354 [inline] mac80211_hwsim_tx_frame_no_nl.isra.0+0x6f4/0x13b0 drivers/net/wireless/mac80211_hwsim.c:1593 mac80211_hwsim_tx_frame+0x1ee/0x2a0 drivers/net/wireless/mac80211_hwsim.c:1884 mac80211_hwsim_beacon_tx+0x49e/0x920 drivers/net/wireless/mac80211_hwsim.c:1938 __iterate_interfaces+0x1e5/0x560 net/mac80211/util.c:793 ieee80211_iterate_active_interfaces_atomic+0x70/0x180 net/mac80211/util.c:829 mac80211_hwsim_beacon+0xcd/0x1c0 drivers/net/wireless/mac80211_hwsim.c:1961 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194 Code: 74 24 10 e8 0a 06 ed f7 48 89 ef e8 12 87 ed f7 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 e3 93 e0 f7 65 8b 05 2c 52 91 76 85 c0 74 0a 5b 5d c3 e8 80 53 RSP: 0018:ffffc90004eef700 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000200 RCX: 1ffffffff1b73199 RDX: 0000000000000000 RSI: ffffffff81807171 RDI: 0000000000000001 RBP: ffffffff9083d9c8 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff81807158 R11: 000000000000001f R12: 0000000000000002 R13: 0000000000000002 R14: dead000000000100 R15: dffffc0000000000 __debug_check_no_obj_freed lib/debugobjects.c:1002 [inline] debug_check_no_obj_freed+0x20c/0x420 lib/debugobjects.c:1023 free_pages_prepare mm/page_alloc.c:1315 [inline] free_pcp_prepare+0x2f0/0xd20 mm/page_alloc.c:1359 free_unref_page_prepare mm/page_alloc.c:3281 [inline] free_unref_page_list+0x16f/0xf80 mm/page_alloc.c:3413 release_pages+0xff1/0x2290 mm/swap.c:980 tlb_batch_pages_flush+0xa8/0x1a0 mm/mmu_gather.c:58 tlb_flush_mmu_free mm/mmu_gather.c:255 [inline] tlb_flush_mmu mm/mmu_gather.c:262 [inline] tlb_finish_mmu+0x147/0x7e0 mm/mmu_gather.c:353 exit_mmap+0x1de/0x4a0 mm/mmap.c:3146 __mmput+0xde/0x450 kernel/fork.c:1181 mmput+0x56/0x60 kernel/fork.c:1203 exit_mm kernel/exit.c:510 [inline] do_exit+0xa12/0x2a00 kernel/exit.c:782 do_group_exit+0xd2/0x2f0 kernel/exit.c:925 get_signal+0x22df/0x24c0 kernel/signal.c:2864 arch_do_signal_or_restart+0x82/0x20f0 arch/x86/kernel/signal.c:869 exit_to_user_mode_loop kernel/entry/common.c:166 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:294 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fba38a890e9 Code: Unable to access opcode bytes at RIP 0x7fba38a890bf. RSP: 002b:00007fba39bb7218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007fba38b9bf68 RCX: 00007fba38a890e9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fba38b9bf68 RBP: 00007fba38b9bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fba38b9bf6c R13: 00007ffc0d1f79ff R14: 00007fba39bb7300 R15: 0000000000022000 NMI backtrace for cpu 0 CPU: 0 PID: 143 Comm: kworker/0:2 Not tainted 5.18.0-rc3-next-20220422-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events nsim_dev_trap_report_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x262/0x3f0 kernel/rcu/tree_stall.h:369 print_cpu_stall kernel/rcu/tree_stall.h:665 [inline] check_cpu_stall kernel/rcu/tree_stall.h:749 [inline] rcu_pending kernel/rcu/tree.c:4068 [inline] rcu_sched_clock_irq.cold+0x144/0x8fc kernel/rcu/tree.c:2755 update_process_times+0x16d/0x200 kernel/time/timer.c:1811 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:243 tick_sched_timer+0xee/0x120 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:kvm_wait+0x98/0x100 arch/x86/kernel/kvm.c:1058 Code: fa 83 e2 07 38 d0 7f 04 84 c0 75 63 0f b6 07 40 38 c6 74 35 48 83 c4 10 c3 c3 e8 23 91 4b 00 eb 07 0f 00 2d da b1 94 08 fb f4 <48> 83 c4 10 c3 89 74 24 0c 48 89 3c 24 e8 56 8f 4b 00 8b 74 24 0c RSP: 0018:ffffc90000007488 EFLAGS: 00000246 RAX: 0000000000000007 RBX: 0000000000000000 RCX: 1ffffffff1b73199 RDX: 0000000000000000 RSI: ffffffff81807171 RDI: ffffffff8134dffd RBP: ffff888019568948 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff81807158 R11: 0000000000000001 R12: 0000000000000000 R13: ffffed10032ad129 R14: 0000000000000001 R15: ffff8880b9c3ae40 pv_wait arch/x86/include/asm/paravirt.h:603 [inline] pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline] __pv_queued_spin_lock_slowpath+0x8c7/0xb50 kernel/locking/qspinlock.c:511 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:85 [inline] do_raw_spin_lock+0x200/0x2a0 kernel/locking/spinlock_debug.c:115 spin_lock include/linux/spinlock.h:354 [inline] task_lock include/linux/sched/task.h:170 [inline] __get_task_comm+0x23/0x50 fs/exec.c:1219 __set_page_owner_handle mm/page_owner.c:174 [inline] __set_page_owner+0x253/0x380 mm/page_owner.c:192 prep_new_page mm/page_alloc.c:2394 [inline] get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4135 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5356 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2273 alloc_slab_page mm/slub.c:1797 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1942 new_slab mm/slub.c:2002 [inline] ___slab_alloc+0x985/0xd90 mm/slub.c:3002 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3089 slab_alloc_node mm/slub.c:3180 [inline] kmem_cache_alloc_node+0x122/0x3f0 mm/slub.c:3264 __alloc_skb+0x215/0x340 net/core/skbuff.c:414 skb_copy+0x139/0x3c0 net/core/skbuff.c:1585 mac80211_hwsim_tx_frame_no_nl.isra.0+0xb7c/0x13b0 drivers/net/wireless/mac80211_hwsim.c:1642 mac80211_hwsim_tx_frame+0x1ee/0x2a0 drivers/net/wireless/mac80211_hwsim.c:1884 mac80211_hwsim_beacon_tx+0x49e/0x920 drivers/net/wireless/mac80211_hwsim.c:1938 __iterate_interfaces+0x1e5/0x560 net/mac80211/util.c:793 ieee80211_iterate_active_interfaces_atomic+0x70/0x180 net/mac80211/util.c:829 mac80211_hwsim_beacon+0xcd/0x1c0 drivers/net/wireless/mac80211_hwsim.c:1961 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:649 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:ffffc9000202f6d8 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000000000 RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffff888012d53cb8 RBP: ffff888012d53ca8 R08: 0000000000000001 R09: ffff888012d53cb4 R10: ffffed10025aa796 R11: 0000000000000001 R12: 000000000000000b R13: 0000000000000010 R14: ffff888012d53c88 R15: 0000000000000007 strscpy_pad+0x62/0x70 lib/string_helpers.c:792 __get_task_comm+0x35/0x50 fs/exec.c:1221 __set_page_owner_handle mm/page_owner.c:174 [inline] __set_page_owner+0x253/0x380 mm/page_owner.c:192 prep_new_page mm/page_alloc.c:2394 [inline] get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4135 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5356 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2273 alloc_slab_page mm/slub.c:1797 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1942 new_slab mm/slub.c:2002 [inline] ___slab_alloc+0x985/0xd90 mm/slub.c:3002 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3089 slab_alloc_node mm/slub.c:3180 [inline] __kmalloc_node_track_caller+0x2cb/0x360 mm/slub.c:4952 kmalloc_reserve net/core/skbuff.c:354 [inline] __alloc_skb+0xde/0x340 net/core/skbuff.c:426 alloc_skb include/linux/skbuff.h:1337 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:742 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:799 [inline] nsim_dev_trap_report_work+0x291/0xba0 drivers/net/netdevsim/dev.c:840 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 ---------------- Code disassembly (best guess): 0: fa cli 1: 83 e2 07 and $0x7,%edx 4: 38 d0 cmp %dl,%al 6: 7f 04 jg 0xc 8: 84 c0 test %al,%al a: 75 63 jne 0x6f c: 0f b6 07 movzbl (%rdi),%eax f: 40 38 c6 cmp %al,%sil 12: 74 35 je 0x49 14: 48 83 c4 10 add $0x10,%rsp 18: c3 retq 19: c3 retq 1a: e8 23 91 4b 00 callq 0x4b9142 1f: eb 07 jmp 0x28 21: 0f 00 2d da b1 94 08 verw 0x894b1da(%rip) # 0x894b202 28: fb sti 29: f4 hlt * 2a: 48 83 c4 10 add $0x10,%rsp <-- trapping instruction 2e: c3 retq 2f: 89 74 24 0c mov %esi,0xc(%rsp) 33: 48 89 3c 24 mov %rdi,(%rsp) 37: e8 56 8f 4b 00 callq 0x4b8f92 3c: 8b 74 24 0c mov 0xc(%rsp),%esi