rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7829/1:b..l (detected by 0, t=10502 jiffies, g=33645, q=201) task:syz.1.1104 state:R running task stack:24352 pid: 7829 ppid: 6242 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:xas_find+0x7a/0xaa0 lib/xarray.c:1240 Code: de e8 2a 24 50 fd 48 83 fb 02 0f 94 c0 48 81 fd 06 c0 ff ff 0f 93 c3 20 c3 48 be fc ff ff ff 03 00 00 00 48 21 ee 41 0f 95 c6 <31> ff e8 ff 23 50 fd 44 84 f3 75 60 48 83 fd 01 74 5a 4c 89 64 24 RSP: 0018:ffffc900030f7708 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8880502a1dc0 RDX: ffffc9000389c000 RSI: 00000000730d9e40 RDI: 0000000000000002 RBP: ffff8880730d9e40 R08: ffffffff84303dc6 R09: fffff940002f0c69 R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc900030f7820 R13: ffffc900030f7838 R14: 0000000000000101 R15: 1ffff9200061ef07 find_get_entry mm/filemap.c:1978 [inline] find_lock_entries+0x22a/0x1030 mm/filemap.c:2092 shmem_undo_range+0x2a3/0x1b50 mm/shmem.c:943 shmem_truncate_range mm/shmem.c:1063 [inline] shmem_evict_inode+0x21b/0xa00 mm/shmem.c:1145 evict+0x2a4/0x620 fs/inode.c:587 __dentry_kill+0x436/0x650 fs/dcache.c:586 dentry_kill+0xbb/0x290 dput+0xd8/0x1a0 fs/dcache.c:893 __fput+0x636/0x8e0 fs/file_table.c:288 task_work_run+0x129/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f1fc2437e9b RSP: 002b:00007f1fc08b6e20 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: ffffffffffffffff RCX: 00007f1fc2437e9b RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000040 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000016 R13: 00007f1fc08b6ec0 R14: 000000000001f1d2 R15: 000000002003e3c0 rcu: rcu_preempt kthread starved for 9880 jiffies! g33645 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:27064 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 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:109 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:570