rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=3e34/1/0x4000000000000000 softirq=26335/26336 fqs=2475 (detected by 0, t=10502 jiffies, g=36741, q=1288 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5343 Comm: kworker/1:3 Not tainted 6.1.0-rc5-next-20221115-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Workqueue: events nsim_dev_trap_report_work RIP: 0010:rcu_rdp_cpu_online kernel/rcu/tree.c:3941 [inline] RIP: 0010:rcu_lockdep_current_cpu_online kernel/rcu/tree.c:3975 [inline] RIP: 0010:rcu_lockdep_current_cpu_online+0x87/0x140 kernel/rcu/tree.c:3959 Code: 3c 02 00 0f 85 a4 00 00 00 48 03 1c ed 00 79 03 8c 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 20 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 87 00 00 00 48 8d 7b 18 48 8b 6b 20 48 b8 00 00 00 00 00 fc RSP: 0018:ffffc900001e0c38 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff8880b9b3c200 RCX: ffffffff816378b9 RDX: 1ffff11017367844 RSI: 0000000000010005 RDI: ffff8880b9b3c220 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8e54b797 R10: fffffbfff1ca96f2 R11: 0000000000000000 R12: 0000000000000001 R13: ffffffff8a4eb020 R14: 0000000000000001 R15: ffff88807d0cb340 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007facb448b038 CR3: 0000000021a1c000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:112 [inline] rcu_read_lock_held_common kernel/rcu/update.c:102 [inline] rcu_read_lock_sched_held+0x29/0x70 kernel/rcu/update.c:123 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x5cf/0x810 kernel/locking/lockdep.c:5679 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x1a/0x70 kernel/locking/spinlock.c:194 debug_object_deactivate lib/debugobjects.c:761 [inline] debug_object_deactivate+0x268/0x300 lib/debugobjects.c:727 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline] debug_deactivate kernel/time/hrtimer.c:481 [inline] __run_hrtimer kernel/time/hrtimer.c:1653 [inline] __hrtimer_run_queues+0x422/0xfb0 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x320/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline] __sysvec_apic_timer_interrupt+0x180/0x640 arch/x86/kernel/apic/apic.c:1113 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:memset_erms+0xd/0x20 arch/x86/lib/memset_64.S:64 Code: 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 66 0f 1f 00 49 89 f9 40 88 f0 48 89 d1 aa 4c 89 c8 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 66 0f 1f RSP: 0018:ffffc90004c1fb70 EFLAGS: 00010246 RAX: ffff888029b40000 RBX: 0000000000001000 RCX: 0000000000000e40 RDX: 0000000000001000 RSI: 0000000000000000 RDI: ffff888029b401c0 RBP: ffff888012042140 R08: 0000000000000001 R09: ffff888029b40000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000082820 R13: 0000000000000001 R14: 0000000000001000 R15: 0000000000000000 slab_post_alloc_hook mm/slab.h:763 [inline] slab_alloc_node mm/slub.c:3433 [inline] __kmem_cache_alloc_node+0x34d/0x430 mm/slub.c:3472 __do_kmalloc_node mm/slab_common.c:954 [inline] __kmalloc_node_track_caller+0x4b/0xc0 mm/slab_common.c:975 kmalloc_reserve net/core/skbuff.c:438 [inline] __alloc_skb+0xe9/0x310 net/core/skbuff.c:511 alloc_skb include/linux/skbuff.h:1269 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:751 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:808 [inline] nsim_dev_trap_report_work+0x2b1/0xc80 drivers/net/netdevsim/dev.c:853 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: rcu_preempt kthread starved for 5549 jiffies! g36741 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:28656 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5229 [inline] __schedule+0xb8a/0x5450 kernel/sched/core.c:6541 schedule+0xde/0x1b0 kernel/sched/core.c:6617 schedule_timeout+0x14e/0x2a0 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1588 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1787 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 8288 Comm: syz-executor.0 Not tainted 6.1.0-rc5-next-20221115-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:csd_lock_wait kernel/smp.c:413 [inline] RIP: 0010:smp_call_function_many_cond+0x43f/0x10a0 kernel/smp.c:987 Code: e6 e8 25 ec 0a 00 45 85 e4 74 48 48 8b 04 24 49 89 c5 83 e0 07 49 c1 ed 03 49 89 c4 4d 01 fd 41 83 c4 03 e8 53 ef 0a 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 4e 0a 00 00 8b 43 08 31 RSP: 0018:ffffc90005d9f818 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9b41b40 RCX: 0000000000000000 RDX: ffff88807ccfba80 RSI: ffffffff8175ad2d RDI: 0000000000000005 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000094001 R12: 0000000000000003 R13: ffffed1017368369 R14: 0000000000000001 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f15b1d13440 CR3: 000000002bd58000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x5a/0xa0 kernel/smp.c:1155 __flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline] flush_tlb_multi arch/x86/mm/tlb.c:943 [inline] flush_tlb_mm_range+0x333/0x4d0 arch/x86/mm/tlb.c:1029 tlb_flush arch/x86/include/asm/tlb.h:20 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:454 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:444 [inline] tlb_flush_mmu mm/mmu_gather.c:293 [inline] tlb_finish_mmu+0x338/0x7e0 mm/mmu_gather.c:386 exit_mmap+0x202/0x7b0 mm/mmap.c:3105 __mmput+0x128/0x4c0 kernel/fork.c:1207 mmput+0x60/0x70 kernel/fork.c:1229 exit_mm kernel/exit.c:516 [inline] do_exit+0x9ac/0x28d0 kernel/exit.c:807 do_group_exit+0xd4/0x2a0 kernel/exit.c:950 get_signal+0x21b1/0x2440 kernel/signal.c:2858 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7ff9880b0361 Code: Unable to access opcode bytes at 0x7ff9880b0337. RSP: 002b:00007ffe97bf73c0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 0000000000000169 RCX: 00007ff9880b0361 RDX: 00007ffe97bf7400 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffe97bf748c R08: 0000000000000000 R09: 00007ffe97bfa080 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 000000000007905a R14: 0000000000000001 R15: 00007ffe97bf74f0