rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8792/1:b..l rcu: (detected by 0, t=10502 jiffies, g=37425, q=187 ncpus=2) task:syz.2.805 state:R running task stack:27096 pid:8792 tgid:8792 ppid:5611 task_flags:0x40004c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7234 preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7413 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:190 spin_unlock include/linux/spinlock.h:390 [inline] zap_pte_range mm/memory.c:1964 [inline] zap_pmd_range mm/memory.c:2020 [inline] zap_pud_range mm/memory.c:2048 [inline] zap_p4d_range mm/memory.c:2069 [inline] __zap_vma_range+0x16f7/0x4a30 mm/memory.c:2109 unmap_vmas+0x299/0x5f0 mm/memory.c:2178 exit_mmap+0x1ef/0xa00 mm/mmap.c:1300 __mmput+0x12a/0x410 kernel/fork.c:1187 mmput+0x67/0x80 kernel/fork.c:1210 exit_mm kernel/exit.c:610 [inline] do_exit+0x8b1/0x2ae0 kernel/exit.c:992 do_group_exit+0xd5/0x2a0 kernel/exit.c:1147 __do_sys_exit_group kernel/exit.c:1158 [inline] __se_sys_exit_group kernel/exit.c:1156 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1156 x64_sys_call+0x102c/0x1530 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6be239de59 RSP: 002b:00007ffe9c109938 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6be239de59 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffe9c10999c R08: 0000000000000000 R09: 00000000000927c0 R10: 00007f6be2626038 R11: 0000000000000246 R12: 00000000000000b0 R13: 00000000000927c0 R14: 000000000004ceb9 R15: 00007ffe9c1099f0 rcu: rcu_preempt kthread timer wakeup didn't happen for 10495 jiffies! g37425 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=18250 rcu: rcu_preempt kthread starved for 10496 jiffies! g37425 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:27528 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0xdd/0x2c0 kernel/sched/core.c:7326 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:trace_lock_acquire include/trace/events/lock.h:23 [inline] RIP: 0010:lock_acquire+0x4a/0x370 kernel/locking/lockdep.c:5831 Code: 65 4c 8b 3d 20 df 7d 12 4c 89 7c 24 30 4d 89 cf 66 90 65 8b 05 3b df 7d 12 83 f8 07 0f 87 da 00 00 00 48 0f a3 05 86 c4 3c 0f <0f> 82 ac 02 00 00 8b 35 4e f8 3c 0f 85 f6 0f 85 c7 00 00 00 48 8b RSP: 0018:ffffc90000a08d60 EFLAGS: 00000097 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88807cbee2c0 RBP: ffff88807cbee2c0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888123eec000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000001000 CR3: 000000005b46f000 CR4: 00000000003526f0 Call Trace: __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:158 spin_lock include/linux/spinlock.h:342 [inline] advance_sched+0xe5/0xd20 net/sched/sch_taprio.c:930 __run_hrtimer kernel/time/hrtimer.c:2032 [inline] __hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2096 hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2215 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: 06 8e 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d c3 d9 12 00 fb f4 bc 48 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197e00 EFLAGS: 00000242 RAX: 0000000001a75025 RBX: ffff88801eaba540 RCX: ffffffff8bb8c2d5 RDX: 0000000000000000 RSI: ffffffff8e1a29fc RDI: ffffffff8c400c80 RBP: ffffed1003d574a8 R08: 0000000000000001 R09: ffffed10170a678d R10: ffff8880b8533c6b R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 1ffff92000032fc4 R15: dffffc0000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:768 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x3a7/0x5b0 kernel/sched/idle.c:355 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x158