rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12872 rcu: (detected by 1, t=10502 jiffies, g=62725, q=17714 ncpus=2) task:syz.2.1062 state:R running task stack:26888 pid:12872 tgid:12870 ppid:11511 task_flags:0x40044c flags:0x00080001 Call Trace: sched_show_task+0x4aa/0x5f0 kernel/sched/core.c:8184 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:292 [inline] print_other_cpu_stall+0xf7b/0x1310 kernel/rcu/tree_stall.h:680 check_cpu_stall kernel/rcu/tree_stall.h:855 [inline] rcu_pending kernel/rcu/tree.c:3708 [inline] rcu_sched_clock_irq+0x93d/0x1050 kernel/rcu/tree.c:2744 update_process_times+0x234/0x2d0 kernel/time/timer.c:2475 tick_sched_handle kernel/time/tick-sched.c:296 [inline] tick_nohz_handler+0x38f/0x6b0 kernel/time/tick-sched.c:317 __run_hrtimer kernel/time/hrtimer.c:2032 [inline] __hrtimer_run_queues+0x3a0/0xaf0 kernel/time/hrtimer.c:2096 hrtimer_interrupt+0x44a/0x900 kernel/time/hrtimer.c:2215 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline] RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline] RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] RIP: 0010:rcu_is_watching+0x5e/0xb0 kernel/rcu/tree.c:752 Code: 03 42 80 3c 38 00 74 08 4c 89 f7 e8 3c 9c 84 00 48 c7 c3 58 6d 9e 92 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 34 <8b> 03 65 ff 0d 59 29 f3 10 74 11 83 e0 04 c1 e8 02 5b 41 5e 41 5f RSP: 0018:ffffc90005dff920 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880b8733d58 RCX: 0000000080000001 RDX: 0000000000000006 RSI: ffffffff8bca5f60 RDI: ffffffff8bca5f20 RBP: 0000000000000001 R08: ffffffff8faf74f7 R09: 1ffffffff1f5ee9e R10: dffffc0000000000 R11: fffffbfff1f5ee9f R12: 1ffff1100728e478 R13: ffff888039471f00 R14: ffffffff8db377d8 R15: dffffc0000000000 rcu_read_unlock include/linux/rcupdate.h:869 [inline] rt_spin_unlock+0x11b/0x200 kernel/locking/spinlock_rt.c:102 spin_unlock_irqrestore include/linux/spinlock_rt.h:129 [inline] vga_put drivers/pci/vgaarb.c:562 [inline] vga_arb_release+0x273/0x5b0 drivers/pci/vgaarb.c:1439 __fput+0x42a/0xa80 fs/file_table.c:512 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x73a/0x2360 kernel/exit.c:1004 do_group_exit+0x22d/0x2f0 kernel/exit.c:1147 get_signal+0x121b/0x12c0 kernel/signal.c:3038 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x104/0x730 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f763d16de59 Code: Unable to access opcode bytes at 0x7f763d16de2f. RSP: 002b:00007f763b3a5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: 000000000000000a RBX: 00007f763d3f6090 RCX: 00007f763d16de59 RDX: 000000000000000a RSI: 0000200000000000 RDI: 0000000000000004 RBP: 00007f763d203e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f763d3f6128 R14: 00007f763d3f6090 R15: 00007ffc49627e68