rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P18244/1:b..l (detected by 1, t=10502 jiffies, g=188273, q=432 ncpus=2) task:modprobe state:R running task stack:24272 pid:18244 ppid:15473 flags:0x00004000 Call Trace: 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_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:215 Code: 00 00 00 00 00 90 53 48 89 fb e8 17 00 00 00 48 8b 3d f0 52 9d 0c 48 89 de 5b e9 67 21 50 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d c4 fc 7f 7e 65 8b 15 c5 fc 7f 7e 81 e2 00 01 ff 00 74 RSP: 0018:ffffc900039e7698 EFLAGS: 00000293 RAX: ffffffff8a19f7d5 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff888079f55940 RSI: 0000000000000001 RDI: 0000000000000004 RBP: ffffc900039e7850 R08: ffff888079f55940 R09: 0000000000000003 R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000001 R13: ffff88807bca2880 R14: ffff88807bca2800 R15: 0000000000000001 mas_data_end lib/maple_tree.c:1492 [inline] mt_validate_nulls lib/maple_tree.c:7200 [inline] mt_validate+0x4545/0x4cb0 lib/maple_tree.c:7249 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 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482 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: 0033:0x7f0844cc1242 RSP: 002b:00007ffce0279248 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f0844994000 RCX: 00007f0844cc1242 RDX: 0000000000000003 RSI: 0000000000002000 RDI: 00007f0844994000 RBP: 0000000000000812 R08: 0000000000000000 R09: 000000000005f000 R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffce0279308 R13: 00007f08449a06b0 R14: 00007ffce0279680 R15: 00000fff9c04f24c rcu: rcu_preempt kthread starved for 5424 jiffies! g188273 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:27608 pid:16 ppid:2 flags:0x00004000 Call Trace: 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 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 10/25/2025 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742 Code: 48 89 df e8 a7 10 9d f7 e9 44 ff ff ff e8 7d 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 87 5d 50 00 fb f4 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: 97bad6fee2d89100 RBX: ffffffff8a3651a7 RCX: 97bad6fee2d89100 RDX: 0000000000000001 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0c20 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: 00007f2764829c50 CR3: 0000000068991000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000083 DR3: ffffffffefffff15 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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