rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P26659/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=320409, q=818 ncpus=2)
task:syz-executor    state:R  running task     stack:23680 pid:26659 tgid:26659 ppid:5215   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:871 [inline]
RIP: 0010:page_ext_put+0xa4/0xc0 mm/page_ext.c:550
Code: c7 80 36 18 8c be 64 03 00 00 48 c7 c2 00 39 18 8c e8 a0 2c 6a ff 48 8d 35 00 00 00 00 48 c7 c7 20 83 93 8e e8 7d f1 69 ff 5b <e9> 27 9a 74 ff e8 f2 87 8d ff 5b e9 b7 3d ea 09 66 2e 0f 1f 84 00
RSP: 0018:ffffc9000325f838 EFLAGS: 00000246
RAX: b5bdbd2df654cc00 RBX: 0000000000000000 RCX: ffffc9000325f703
RDX: 0000000000000000 RSI: ffffffff8c0ae6e0 RDI: ffffffff8c606d40
RBP: ffff88813fffa7b0 R08: ffffffff9017f16f R09: 1ffffffff202fe2d
R10: dffffc0000000000 R11: fffffbfff202fe2e R12: 0000000000000001
R13: 0000000000000001 R14: ffffea0000d01c40 R15: 0000000000000000
 page_table_check_alloc include/linux/page_table_check.h:33 [inline]
 post_alloc_hook+0x206/0x230 mm/page_alloc.c:1494
 prep_new_page mm/page_alloc.c:1501 [inline]
 get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3439
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4695
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2263
 vm_area_alloc_pages mm/vmalloc.c:3584 [inline]
 __vmalloc_area_node mm/vmalloc.c:3653 [inline]
 __vmalloc_node_range_noprof+0xa40/0x1400 mm/vmalloc.c:3834
 vmalloc_user_noprof+0x74/0x80 mm/vmalloc.c:3988
 kcov_ioctl+0x59/0x640 kernel/kcov.c:715
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xfe/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2ab5379a7b
RSP: 002b:00007ffe335bb080 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000100000 RCX: 00007f2ab5379a7b
RDX: 0000000000100000 RSI: ffffffff80086301 RDI: 00000000000000d7
RBP: 00007f2ab5515f40 R08: 00000000000000da R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10484 jiffies! g320409 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:26288 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
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:48 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111