rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=4b04/1/0x4000000000000000 softirq=74026/74026 fqs=0
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P15003/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=56617, q=462 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 14996 Comm: syz-executor Not tainted 6.15.0-rc3-syzkaller-00001-g9d7a0577c9db #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:lock_is_held_type+0x56/0x1a0 kernel/locking/lockdep.c:5931
Code: 30 04 00 0f 84 0e 01 00 00 65 8b 05 c4 f7 38 07 85 c0 0f 85 ff 00 00 00 65 4c 8b 24 25 08 60 68 93 41 83 bc 24 ec 0a 00 00 00 <0f> 85 e7 00 00 00 41 89 f6 49 89 ff 48 c7 04 24 00 00 00 00 9c 8f
RSP: 0018:ffffc90000a08c28 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 00000000ffffffff RCX: ffff888030e9da00
RDX: ffff888030e9da00 RSI: 00000000ffffffff RDI: ffff888058772300
RBP: ffffffff93686020 R08: ffffffff8a25dfcb R09: fffff5200014117c
R10: dffffc0000000000 R11: fffff5200014117c R12: ffff888030e9da00
R13: ffffffff8a25df10 R14: ffff888058772340 R15: ffff888030e9e4d8
FS:  0000555568636500(0000) GS:ffff88812509a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33717ff8 CR3: 000000004f300000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 lock_is_held include/linux/lockdep.h:249 [inline]
 advance_sched+0xcd/0xca0 net/sched/sch_taprio.c:925
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x5a8/0xd40 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:prepare_alloc_pages+0x205/0x610 mm/page_alloc.c:4744
Code: c7 c7 b3 09 57 8e be 41 01 00 00 e8 c5 02 73 ff 2e 2e 2e 31 c0 48 be 00 00 00 00 00 fc ff df 4c 89 eb 48 c1 eb 03 0f b6 04 33 <84> c0 0f 85 1f 02 00 00 41 f6 45 01 04 75 21 44 89 ff 8b 74 24 1c
RSP: 0018:ffffc900042579c8 EFLAGS: 00000216
RAX: 0000000000000004 RBX: 1ffff9200084af50 RCX: ffff888030e9da00
RDX: ffff888030e9da00 RSI: dffffc0000000000 RDI: ffffffff8ca1b680
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffc90004257aa0
R13: ffffc90004257a80 R14: 0000000000000000 R15: 0000000000002dc2
 __alloc_frozen_pages_noprof+0x162/0x5b0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301
 alloc_frozen_pages_noprof mm/mempolicy.c:2372 [inline]
 alloc_pages_noprof+0x121/0x190 mm/mempolicy.c:2392
 vm_area_alloc_pages mm/vmalloc.c:3591 [inline]
 __vmalloc_area_node mm/vmalloc.c:3669 [inline]
 __vmalloc_node_range_noprof+0x9cb/0x1390 mm/vmalloc.c:3844
 vmalloc_user_noprof+0x74/0x80 mm/vmalloc.c:3996
 kcov_ioctl+0x56/0x640 kernel/kcov.c:716
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf3/0x160 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f493c78dd6b
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007ffe1da2cc40 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000100000 RCX: 00007f493c78dd6b
RDX: 0000000000100000 RSI: ffffffff80086301 RDI: 00000000000000d7
RBP: 00007f493c9b5f40 R08: 00000000000000da R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
 </TASK>
task:syz.7.2531      state:R  running task     stack:25960 pid:15003 tgid:15002 ppid:7067   task_flags:0x40054c flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x1b88/0x5240 kernel/sched/core.c:6767
 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6947
 preempt_schedule+0xe4/0xf0 kernel/sched/core.c:6971
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 zap_pte_range mm/memory.c:1761 [inline]
 zap_pmd_range mm/memory.c:1823 [inline]
 zap_pud_range mm/memory.c:1852 [inline]
 zap_p4d_range mm/memory.c:1873 [inline]
 unmap_page_range+0x39c5/0x44d0 mm/memory.c:1894
 unmap_vmas+0x3ce/0x5f0 mm/memory.c:1984
 exit_mmap+0x2bc/0xde0 mm/mmap.c:1284
 __mmput+0x115/0x420 kernel/fork.c:1379
 exit_mm+0x221/0x310 kernel/exit.c:589
 do_exit+0x994/0x27f0 kernel/exit.c:940
 do_group_exit+0x207/0x2c0 kernel/exit.c:1102
 get_signal+0x1696/0x1730 kernel/signal.c:3034
 arch_do_signal_or_restart+0x98/0x810 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218
 do_syscall_64+0x100/0x210 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9a4938e169
RSP: 002b:00007f9a4a25d0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f9a495b5fa8 RCX: 00007f9a4938e169
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f9a495b5fa8
RBP: 00007f9a495b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9a495b5fac
R13: 0000000000000000 R14: 00007fff16ae5750 R15: 00007fff16ae5838
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g56617 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=29865
rcu: rcu_preempt kthread starved for 10502 jiffies! g56617 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:26976 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x1b88/0x5240 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x163/0x360 kernel/sched/core.c:6860
 schedule_timeout+0x15b/0x2b0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2e1/0x1340 kernel/rcu/tree.c:2046
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2248
 kthread+0x7b9/0x940 kernel/kthread.c:464
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>