rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5436/1:b..l (detected by 0, t=10502 jiffies, g=16105, q=314 ncpus=2) task:syz.0.674 state:R running task stack:24664 pid:5436 ppid:3548 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6561 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 cf b2 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc9000311f5c0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000623ec4 RCX: 1ffff92000623e64 RDX: dffffc0000000000 RSI: ffffffff8aec13c0 RDI: ffffffff8b3d48a0 RBP: ffffc9000311f708 R08: dffffc0000000000 R09: fffffbfff2093845 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000623ec0 R13: dffffc0000000000 R14: ffffc9000311f620 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] filemap_map_pages+0x294/0x12c0 mm/filemap.c:3415 do_fault_around mm/memory.c:4581 [inline] do_read_fault mm/memory.c:4607 [inline] do_fault mm/memory.c:4741 [inline] handle_pte_fault mm/memory.c:5013 [inline] __handle_mm_fault mm/memory.c:5155 [inline] handle_mm_fault+0x33e2/0x5340 mm/memory.c:5276 faultin_page mm/gup.c:1009 [inline] __get_user_pages+0x4f3/0x1190 mm/gup.c:1233 populate_vma_page_range+0x217/0x2b0 mm/gup.c:1590 __mm_populate+0x275/0x440 mm/gup.c:1704 mm_populate include/linux/mm.h:2797 [inline] vm_mmap_pgoff+0x22b/0x2d0 mm/util.c:525 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe50fd75b59 RSP: 002b:00007fe510bc9048 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fe50ff05f60 RCX: 00007fe50fd75b59 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007fe50fde4e5d R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fe50ff05f60 R15: 00007ffcc070b888 rcu: rcu_preempt kthread timer wakeup didn't happen for 10503 jiffies! g16105 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=8232 rcu: rcu_preempt kthread starved for 10509 jiffies! g16105 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:25528 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6561 schedule+0xbf/0x180 kernel/sched/core.c:6637 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567