rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6066 rcu: (detected by 0, t=10503 jiffies, g=11045, q=2041 ncpus=2) task:syz.2.49 state:R running task stack:27016 pid:6066 ppid:5786 flags:0x0000400e Call Trace: sched_show_task+0x481/0x5a0 kernel/sched/core.c:9179 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:261 [inline] print_other_cpu_stall+0xfa7/0x1340 kernel/rcu/tree_stall.h:637 check_cpu_stall kernel/rcu/tree_stall.h:809 [inline] rcu_pending kernel/rcu/tree.c:3950 [inline] rcu_sched_clock_irq+0x87c/0x1220 kernel/rcu/tree.c:2295 update_process_times+0x147/0x1b0 kernel/time/timer.c:2071 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x3a2/0x580 kernel/time/tick-sched.c:1492 __run_hrtimer kernel/time/hrtimer.c:1755 [inline] __hrtimer_run_queues+0x4df/0xc40 kernel/time/hrtimer.c:1819 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1881 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x51/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:variable_ffs arch/x86/include/asm/bitops.h:319 [inline] RIP: 0010:handle_softirqs+0x1b0/0x820 kernel/softirq.c:566 Code: 89 64 24 2c 0f b7 db 48 c7 c7 a0 b1 a9 8a e8 47 19 1d 09 65 66 c7 05 1d 35 b2 7e 00 00 e8 88 74 3a 00 fb 49 c7 c6 c0 a0 a0 8c <89> 5c 24 34 b8 ff ff ff ff 0f bc 44 24 34 41 89 c5 41 ff c5 0f 84 RSP: 0018:ffffc90000007e40 EFLAGS: 00000286 RAX: c5309b00a2524900 RBX: 0000000000000200 RCX: c5309b00a2524900 RDX: dffffc0000000000 RSI: ffffffff8aaab940 RDI: ffffffff8afc7880 RBP: ffffc90000007f50 R08: ffffffff90da6537 R09: 1ffffffff21b4ca6 R10: dffffc0000000000 R11: fffffbfff21b4ca7 R12: 000000000000000a R13: 0000000000000000 R14: ffffffff8ca0a0c0 R15: ffff88801af35a00 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0xa1/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:723 RIP: 0010:rcu_read_unlock_special+0x88/0x4c0 kernel/rcu/tree_plugin.h:682 Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 19 5e 93 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b RSP: 0018:ffffc90004f5fc00 EFLAGS: 00000206 RAX: c5309b00a2524900 RBX: 1ffff920009ebf88 RCX: c5309b00a2524900 RDX: dffffc0000000000 RSI: ffffffff8aaab940 RDI: ffffffff8afc7880 RBP: ffffc90004f5fcf0 R08: ffffffff90da6537 R09: 1ffffffff21b4ca6 R10: dffffc0000000000 R11: fffffbfff21b4ca7 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000246 R15: ffffffff8cd35398 __rcu_read_unlock+0x7c/0xd0 kernel/rcu/tree_plugin.h:426 rcu_read_unlock+0x85/0xa0 include/linux/rcupdate.h:818 dput+0xe6/0x1e0 fs/dcache.c:911 __fput+0x5e5/0x970 fs/file_table.c:392 task_work_run+0x1ce/0x250 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f7317d8e929 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff7ee2fc58 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f7317fb7ba0 RCX: 00007f7317d8e929 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f7317fb7ba0 R08: 000000000000f74c R09: 000000117ee2ff4f R10: 00000000005ebff4 R11: 0000000000000246 R12: 00000000000185d9 R13: 00007f7317fb6080 R14: ffffffffffffffff R15: 00007fff7ee2fd70