rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4905/1:b..l P4900/1:b..l
	(detected by 1, t=10502 jiffies, g=11165, q=47 ncpus=2)
task:dhcpcd-run-hook state:R  running task     stack:24160 pid:4900  ppid:3933   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696
RIP: 0010:mas_data_end lib/maple_tree.c:1491 [inline]
RIP: 0010:mt_validate_nulls lib/maple_tree.c:7198 [inline]
RIP: 0010:mt_validate+0x45a1/0x4c90 lib/maple_tree.c:7247
Code: 4c 24 40 4c 8d 2c c1 4c 89 e8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ef e8 4d ce cb f7 4d 8b 6d 00 31 ff 4c 89 ee e8 cf b5 7b f7 <4d> 85 ed 0f 85 10 02 00 00 e8 e1 b1 7b f7 4d 8d be f8 00 00 00 4c
RSP: 0018:ffffc900046973c0 EFLAGS: 00000293
RAX: ffffffff8a051e31 RBX: dffffc0000000000 RCX: ffff88801f673b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004697590 R08: ffff88801f673b80 R09: 0000000000000003
R10: 0000000000000003 R11: 0000000000000000 R12: 000000000000000e
R13: 0000000000000000 R14: ffff888060d2d800 R15: 0000000000000001
 validate_mm_mt+0xcd/0x420 mm/mmap.c:295
 validate_mm+0xcc/0x2b0 mm/mmap.c:332
 remove_mt mm/mmap.c:2322 [inline]
 do_mas_align_munmap+0xf98/0x1220 mm/mmap.c:2595
 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650
 __mmap_region mm/mmap.c:2698 [inline]
 mmap_region+0x6e5/0x1c70 mm/mmap.c:2916
 do_mmap+0x958/0xfd0 mm/mmap.c:1436
 vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:520
 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f4acbecc242
RSP: 002b:00007ffd514e8138 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f4acbba8000 RCX: 00007f4acbecc242
RDX: 0000000000000003 RSI: 0000000000002000 RDI: 00007f4acbba8000
RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000006000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffd514e81f8
R13: 00007f4acbbab0c0 R14: 00007ffd514e8570 R15: 00000fffaa29d02a
 </TASK>
task:udevd           state:R  running task     stack:27584 pid:4905  ppid:3638   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730
 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 filemap_map_pages+0xe27/0x10d0 mm/filemap.c:3499
 do_fault_around mm/memory.c:4600 [inline]
 do_read_fault mm/memory.c:4626 [inline]
 do_fault mm/memory.c:4760 [inline]
 handle_pte_fault mm/memory.c:5031 [inline]
 __handle_mm_fault mm/memory.c:5173 [inline]
 handle_mm_fault+0x2889/0x3e70 mm/memory.c:5294
 do_user_addr_fault+0x51f/0xb10 arch/x86/mm/fault.c:1340
 handle_page_fault arch/x86/mm/fault.c:1431 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1487
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f4f5490a9e0
RSP: 002b:00007fff4ccb42f8 EFLAGS: 00010246
RAX: 00007f4f54f82b40 RBX: 0000000000000000 RCX: 00007f4f5485ff07
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 00007f4f54f82880 R08: 00007f4f549f2b60 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 00007f4f5507fb10
R13: 0000000000000000 R14: 0000000000000000 R15: 00007f4f5507fb10
 </TASK>
rcu: rcu_preempt kthread starved for 10552 jiffies! g11165 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:26912 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742
Code: 48 89 df e8 37 b2 af f7 e9 4c ff ff ff e8 fd 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 87 63 65 00 fb f4 <c3> 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffc90000177de8 EFLAGS: 000002c6
RAX: 564182c25fb06d00 RBX: ffffffff8a213f27 RCX: 564182c25fb06d00
RDX: 0000000000000001 RSI: ffffffff8a8c0300 RDI: ffffffff8adefae0
RBP: ffffc90000177f20 R08: dffffc0000000000 R09: ffffed10171e6af6
R10: ffffed10171e6af6 R11: 1ffff110171e6af5 R12: 0000000000000001
R13: dffffc0000000000 R14: ffff888017739dc0 R15: 1ffffffff1c3ee66
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005627efd00258 CR3: 000000005cfe4000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 default_idle_call+0x84/0xc0 kernel/sched/idle.c:109
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1fc/0x570 kernel/sched/idle.c:303
 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401
 start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281
 secondary_startup_64_no_verify+0xcf/0xdb
 </TASK>