rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=175/1/0x4000000000000000 softirq=25343/25344 fqs=1 (detected by 1, t=10502 jiffies, g=34885, q=380) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 8295 Comm: syz-executor.1 Not tainted 5.17.0-rc5-syzkaller-00189-g53ab78cd6d5a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__kasan_check_read+0x0/0x10 mm/kasan/shadow.c:31 Code: 8b e8 b6 41 4a 07 48 85 db 0f 85 86 a7 4b 07 48 83 c4 60 5b 5d 41 5c 41 5d c3 c3 e9 86 a8 4b 07 cc cc cc cc cc cc cc cc cc cc <48> 8b 0c 24 89 f6 31 d2 e9 f3 f9 ff ff 0f 1f 00 48 8b 0c 24 89 f6 RSP: 0018:ffffc90000007b60 EFLAGS: 00000013 RAX: 0000000000000031 RBX: ffff8880764b4460 RCX: 1ffff1100ec96895 RDX: 1ffffffff200b153 RSI: 0000000000000008 RDI: ffffffff8ffc3ac8 RBP: 0000000000000c66 R08: 0000000000000000 R09: ffffffff8ffc3acf R10: fffffbfff1ff8759 R11: 0000000000000001 R12: ffff8880764b4488 R13: ffff8880764b3a00 R14: 0000000000000002 R15: 0000000000044000 FS: 00007f13e9f3a700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555564de848 CR3: 000000001d464000 CR4: 0000000000350ef0 Call Trace: 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:199 [inline] check_wait_context kernel/locking/lockdep.c:4701 [inline] __lock_acquire+0x481/0x56c0 kernel/locking/lockdep.c:4977 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:349 [inline] advance_sched+0x53/0x9a0 net/sched/sch_taprio.c:714 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__sanitizer_cov_trace_pc+0x43/0x60 kernel/kcov.c:206 Code: 70 02 00 a9 00 01 ff 00 74 0e 85 c9 74 35 8b 82 a4 15 00 00 85 c0 74 2b 8b 82 80 15 00 00 83 f8 02 75 20 48 8b 8a 88 15 00 00 <8b> 92 84 15 00 00 48 8b 01 48 83 c0 01 48 39 c2 76 07 48 89 34 c1 RSP: 0018:ffffc900046bfae0 EFLAGS: 00000246 RAX: 0000000000000002 RBX: 1ffff920008d7f5d RCX: ffffc90003f5a000 RDX: ffff8880764b3a00 RSI: ffffffff8136859c RDI: 0000000073bff067 RBP: dffffc0000000000 R08: 0000000000000000 R09: ffff8880764b3a07 R10: ffffffff81ad1a49 R11: 0000000000000000 R12: 0000000073bff007 R13: 0000000020053000 R14: 0000000000001052 R15: ffff88801dac6000 pud_huge+0x5c/0xd0 arch/x86/mm/hugetlbpage.c:73 follow_pud_mask mm/gup.c:757 [inline] follow_p4d_mask mm/gup.c:807 [inline] follow_page_mask+0x2b1/0x1530 mm/gup.c:866 __get_user_pages+0x41a/0xf60 mm/gup.c:1188 populate_vma_page_range+0x24d/0x330 mm/gup.c:1522 __mm_populate+0x1ea/0x3e0 mm/gup.c:1631 mm_populate include/linux/mm.h:2702 [inline] vm_mmap_pgoff+0x20e/0x290 mm/util.c:524 ksys_mmap_pgoff+0x40d/0x5a0 mm/mmap.c:1630 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f13eb5e6049 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f13e9f3a168 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f13eb6f9030 RCX: 00007f13eb5e6049 RDX: 0000000000000002 RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007f13eb64008d R08: 0000000000000003 R09: 0000000000000000 R10: 0000000000028011 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe5b86597f R14: 00007f13e9f3a300 R15: 0000000000022000 rcu: rcu_preempt kthread starved for 10500 jiffies! g34885 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:28664 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4995 [inline] __schedule+0xa94/0x4910 kernel/sched/core.c:6304 schedule+0xd2/0x260 kernel/sched/core.c:6377 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1963 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2136 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 10 Comm: kworker/u4:1 Not tainted 5.17.0-rc5-syzkaller-00189-g53ab78cd6d5a #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+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_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:458 print_other_cpu_stall kernel/rcu/tree_stall.h:563 [inline] check_cpu_stall kernel/rcu/tree_stall.h:706 [inline] rcu_pending kernel/rcu/tree.c:3919 [inline] rcu_sched_clock_irq+0x2068/0x2110 kernel/rcu/tree.c:2617 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428 __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:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline] RIP: 0010:smp_call_function_many_cond+0x4e6/0xc90 kernel/smp.c:969 Code: 0b 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 ac 89 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 e9 05 00 00 8b 43 08 31 RSP: 0018:ffffc90000cf79f0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9c41fa0 RCX: 0000000000000000 RDX: ffff888011911d00 RSI: ffffffff816d6214 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff816d623a R11: 0000000000000000 R12: ffffed10173883f5 R13: 0000000000000000 R14: ffff8880b9c41fa8 R15: 0000000000000001 on_each_cpu_cond_mask+0x56/0xa0 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+0x21d/0x6f0 arch/x86/kernel/alternative.c:1300 text_poke_flush arch/x86/kernel/alternative.c:1470 [inline] text_poke_flush arch/x86/kernel/alternative.c:1467 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1477 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 jump_label_update+0x32f/0x410 kernel/jump_label.c:830 static_key_enable_cpuslocked+0x1b1/0x260 kernel/jump_label.c:177 static_key_enable+0x16/0x20 kernel/jump_label.c:190 toggle_allocation_gate mm/kfence/core.c:735 [inline] toggle_allocation_gate+0x100/0x390 mm/kfence/core.c:727 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 8b e8 mov %eax,%ebp 2: b6 41 mov $0x41,%dh 4: 4a 07 rex.WX (bad) 6: 48 85 db test %rbx,%rbx 9: 0f 85 86 a7 4b 07 jne 0x74ba795 f: 48 83 c4 60 add $0x60,%rsp 13: 5b pop %rbx 14: 5d pop %rbp 15: 41 5c pop %r12 17: 41 5d pop %r13 19: c3 retq 1a: c3 retq 1b: e9 86 a8 4b 07 jmpq 0x74ba8a6 20: cc int3 21: cc int3 22: cc int3 23: cc int3 24: cc int3 25: cc int3 26: cc int3 27: cc int3 28: cc int3 29: cc int3 * 2a: 48 8b 0c 24 mov (%rsp),%rcx <-- trapping instruction 2e: 89 f6 mov %esi,%esi 30: 31 d2 xor %edx,%edx 32: e9 f3 f9 ff ff jmpq 0xfffffa2a 37: 0f 1f 00 nopl (%rax) 3a: 48 8b 0c 24 mov (%rsp),%rcx 3e: 89 f6 mov %esi,%esi