rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (0 ticks this GP) idle=5cf/1/0x4000000000000000 softirq=164144/164145 fqs=4 (detected by 1, t=10502 jiffies, g=280433, q=108) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 18798 Comm: syz-executor.4 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_smp_processor_id+0x5/0x20 lib/smp_processor_id.c:60 Code: 48 c7 c7 a0 cd 79 8a e8 f9 01 00 00 65 ff 0d 1e ed f0 75 5b 5d c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 <48> c7 c7 20 49 d5 8a 48 c7 c6 60 49 d5 8a eb 0b 66 2e 0f 1f 84 00 RSP: 0018:ffffc90000007518 EFLAGS: 00000086 RAX: 0000000000000001 RBX: 1ffff92000000ea8 RCX: ffff888077e23a00 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8dfe8da8 RBP: ffffc900000075c8 R08: dffffc0000000000 R09: fffffbfff1bfd1b6 R10: fffffbfff1bfd1b6 R11: 0000000000000000 R12: 0000000000000000 R13: 1ffff92000000ecc R14: dffffc0000000000 R15: 0000000000000000 FS: 00007fa120781700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000154647000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:330 [inline] rcu_is_watching+0x12/0xa0 kernel/rcu/tree.c:1121 rcu_read_lock_held_common kernel/rcu/update.c:108 [inline] rcu_read_lock_sched_held+0x6b/0x130 kernel/rcu/update.c:123 trace_lock_acquire+0x59/0x190 include/trace/events/lock.h:13 lock_acquire+0xa5/0x4d0 kernel/locking/lockdep.c:5608 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1689 [inline] __hrtimer_run_queues+0x546/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x3e/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:creds_are_invalid kernel/cred.c:832 [inline] RIP: 0010:__validate_creds include/linux/cred.h:188 [inline] RIP: 0010:exit_creds+0x70/0x320 kernel/cred.c:170 Code: ef e8 94 dc 77 00 48 c7 45 00 00 00 00 00 4d 8d 7c 24 10 4c 89 fd 48 c1 ed 03 42 8a 44 2d 00 84 c0 0f 85 d5 01 00 00 41 8b 1f 64 65 73 43 89 de e8 34 0c 2c 00 81 fb 64 65 73 43 0f 85 32 02 RSP: 0018:ffffc90000007bb0 EFLAGS: 00000246 RAX: ffffffff81588e00 RBX: 0000000043736564 RCX: ffff888077e23a00 RDX: 0000000080000100 RSI: 0000000000000100 RDI: ffff88803f1b3a00 RBP: 1ffff110044f9b62 R08: dffffc0000000000 R09: fffffbfff1bfd1b6 R10: fffffbfff1bfd1b6 R11: 0000000000000000 R12: ffff8880227cdb00 R13: dffffc0000000000 R14: ffff88803f1b3a00 R15: ffff8880227cdb10 __put_task_struct+0x105/0x2c0 kernel/fork.c:753 rcu_do_batch kernel/rcu/tree.c:2506 [inline] rcu_core+0x9b8/0x1610 kernel/rcu/tree.c:2741 __do_softirq+0x392/0x7a3 kernel/softirq.c:558 __irq_exit_rcu+0xec/0x170 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:__rcu_read_unlock+0x0/0x650 kernel/rcu/tree_plugin.h:415 Code: 60 00 eb b2 44 89 f9 80 e1 07 80 c1 03 38 c1 7c b0 4c 89 ff e8 b1 a6 60 00 eb a6 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec c0 00 RSP: 0018:ffffc9000adaf780 EFLAGS: 00000246 RAX: ffffffff81915000 RBX: 0000000000000000 RCX: 0000000000040000 RDX: ffffc9000aab4000 RSI: 00000000000003be RDI: 00000000000003bf RBP: dffffc0000000000 R08: ffffffff81914ff8 R09: fffffbfff1ff35dd R10: fffffbfff1ff35dd R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000000 R14: 00007fa12182cae9 R15: 0000000000000000 rcu_read_unlock include/linux/rcupdate.h:720 [inline] is_bpf_text_address+0x247/0x270 kernel/bpf/core.c:717 kernel_text_address+0x9e/0xd0 kernel/extable.c:124 __kernel_text_address+0x9/0x40 kernel/extable.c:78 unwind_get_return_address+0x48/0x80 arch/x86/kernel/unwind_orc.c:318 arch_stack_walk+0xf8/0x140 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x11b/0x1e0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0xb6/0xf0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:3234 [inline] slab_alloc mm/slub.c:3242 [inline] kmem_cache_alloc+0x1c9/0x310 mm/slub.c:3247 kmem_cache_zalloc include/linux/slab.h:714 [inline] __alloc_file+0x26/0x2f0 fs/file_table.c:101 alloc_empty_file+0xa9/0x1b0 fs/file_table.c:150 alloc_file+0x58/0x4f0 fs/file_table.c:192 alloc_file_pseudo+0x272/0x300 fs/file_table.c:232 sock_alloc_file+0xb4/0x240 net/socket.c:462 sock_map_fd net/socket.c:486 [inline] __sys_socket+0x198/0x380 net/socket.c:1561 __do_sys_socket net/socket.c:1566 [inline] __se_sys_socket net/socket.c:1564 [inline] __x64_sys_socket+0x76/0x80 net/socket.c:1564 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa12182cae9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa120781188 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 00007fa121940028 RCX: 00007fa12182cae9 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000010 RBP: 00007fa121886ff7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff4518aa4f R14: 00007fa120781300 R15: 0000000000022000 rcu: rcu_preempt kthread starved for 10494 jiffies! g280433 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:26576 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xb72/0x1460 kernel/sched/core.c:6253 schedule+0x12b/0x1f0 kernel/sched/core.c:6326 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x1fd/0x770 kernel/rcu/tree.c:1955 rcu_gp_kthread+0xa5/0x350 kernel/rcu/tree.c:2128 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 8 Comm: kworker/u4:0 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound toggle_allocation_gate Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_check_gp_kthread_starvation+0x1ff/0x270 kernel/rcu/tree_stall.h:481 print_other_cpu_stall kernel/rcu/tree_stall.h:586 [inline] check_cpu_stall kernel/rcu/tree_stall.h:729 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq+0x23d5/0x2bc0 kernel/rcu/tree.c:2597 update_process_times+0x197/0x200 kernel/time/timer.c:1785 tick_sched_handle kernel/time/tick-sched.c:226 [inline] tick_sched_timer+0x27d/0x420 kernel/time/tick-sched.c:1428 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4cb/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline] RIP: 0010:smp_call_function_many_cond+0xbb2/0xda0 kernel/smp.c:969 Code: 83 e6 01 31 ff e8 fe b7 0b 00 41 83 e7 01 49 bf 00 00 00 00 00 fc ff df 75 0e e8 d9 b3 0b 00 eb 4c 0f 1f 80 00 00 00 00 f3 90 <42> 0f b6 04 3b 84 c0 75 11 41 f7 45 00 01 00 00 00 74 2b e8 b6 b3 RSP: 0018:ffffc90000cd7820 EFLAGS: 00000293 RAX: ffffffff8178e3ca RBX: 1ffff1101734831d RCX: ffff888012015700 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000cd7960 R08: ffffffff8178e392 R09: ffffffff844a3b20 R10: 0000000000000009 R11: ffff888012015700 R12: 0000000000000000 R13: ffff8880b9a418e8 R14: ffff8880b9b3a640 R15: dffffc0000000000 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1112 [inline] text_poke_bp_batch+0x310/0x940 arch/x86/kernel/alternative.c:1297 text_poke_flush arch/x86/kernel/alternative.c:1451 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1458 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x12d/0x250 kernel/jump_label.c:177 static_key_enable+0x16/0x20 kernel/jump_label.c:190 toggle_allocation_gate+0xbf/0x460 mm/kfence/core.c:732 process_one_work+0x853/0x1140 kernel/workqueue.c:2298 worker_thread+0xac1/0x1320 kernel/workqueue.c:2445 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 ---------------- Code disassembly (best guess): 0: 48 c7 c7 a0 cd 79 8a mov $0xffffffff8a79cda0,%rdi 7: e8 f9 01 00 00 callq 0x205 c: 65 ff 0d 1e ed f0 75 decl %gs:0x75f0ed1e(%rip) # 0x75f0ed31 13: 5b pop %rbx 14: 5d pop %rbp 15: c3 retq 16: cc int3 17: cc int3 18: cc int3 19: cc int3 1a: cc int3 1b: cc int3 1c: cc int3 1d: cc int3 1e: cc int3 1f: cc int3 20: cc int3 21: cc int3 22: cc int3 23: cc int3 24: cc int3 25: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) * 2a: 48 c7 c7 20 49 d5 8a mov $0xffffffff8ad54920,%rdi <-- trapping instruction 31: 48 c7 c6 60 49 d5 8a mov $0xffffffff8ad54960,%rsi 38: eb 0b jmp 0x45 3a: 66 data16 3b: 2e cs 3c: 0f .byte 0xf 3d: 1f (bad) 3e: 84 00 test %al,(%rax)