rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P10075/1:b..l
	(detected by 1, t=10502 jiffies, g=97281, q=56 ncpus=2)
task:udevd           state:R  running task     stack:22928 pid:10075 ppid:3639   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696
RIP: 0010:ma_is_root lib/maple_tree.c:339 [inline]
RIP: 0010:mte_is_root lib/maple_tree.c:344 [inline]
RIP: 0010:mas_validate_gaps lib/maple_tree.c:7019 [inline]
RIP: 0010:mt_validate+0x3464/0x4cb0 lib/maple_tree.c:7246
Code: 48 8b 7c 24 18 e8 fc c5 b8 f7 e9 0e ff ff ff e8 22 db 67 f7 eb 05 e8 1b db 67 f7 49 bc 00 00 00 00 00 fc ff df 48 8b 5c 24 40 <49> 89 dd 49 c1 ed 03 43 80 7c 25 00 00 74 08 48 89 df e8 f5 c5 b8
RSP: 0018:ffffc90005edf700 EFLAGS: 00000293
RAX: ffffffff8a1a9795 RBX: ffff888062f8be00 RCX: ffff888019b1bb80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90005edf8b0 R08: ffff888019b1bb80 R09: 0000000000000004
R10: 0000000000000003 R11: 0000000000000000 R12: dffffc0000000000
R13: ffffffff8bb17fa1 R14: ffff88807c0b65e8 R15: 0000000000001000
 validate_mm_mt+0xe2/0x440 mm/mmap.c:295
 validate_mm+0xe1/0x2e0 mm/mmap.c:332
 mmap_region+0x78a/0x1ca0 mm/mmap.c:2922
 do_mmap+0x964/0xfd0 mm/mmap.c:1436
 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:520
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f05c511d822
RSP: 002b:00007ffc8de624d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f05c511d822
RDX: 0000000000000003 RSI: 0000000000000200 RDI: 0000000000000000
RBP: 0000000000000022 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000002600 R14: 0000562a187920b0 R15: 0000000000010000
 </TASK>
rcu: rcu_preempt kthread starved for 10532 jiffies! g97281 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:27408 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x99/0x3b0 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 02/12/2026
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742
Code: 48 89 df e8 e7 5f 9c f7 e9 44 ff ff ff e8 3d 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 77 ac 4f 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: 47a71407d9f82000 RBX: ffffffff8a3702b7 RCX: 47a71407d9f82000
RDX: 0000000000000001 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0f60
RBP: ffffc90000177f20 R08: ffff8880b8f3580b R09: 1ffff110171e6b01
R10: dffffc0000000000 R11: ffffed10171e6b02 R12: 1ffff9200002efc8
R13: dffffc0000000000 R14: ffff888017731dc0 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd5a61e34e8 CR3: 0000000056e9c000 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+0x20d/0x5a0 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>