rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P20054/1:b..l rcu: (detected by 0, t=10502 jiffies, g=109797, q=339 ncpus=2) task:syz.0.3589 state:R running task stack:26080 pid:20054 tgid:20053 ppid:16869 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5282 [inline] __schedule+0x14ed/0x5040 kernel/sched/core.c:6894 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7078 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0xe1/0x130 kernel/softirq.c:457 local_bh_enable include/linux/bottom_half.h:33 [inline] xdp_test_run_batch net/bpf/test_run.c:357 [inline] bpf_test_run_xdp_live+0x1880/0x1b20 net/bpf/test_run.c:379 bpf_prog_test_run_xdp+0x7de/0x1100 net/bpf/test_run.c:1396 bpf_prog_test_run+0x2c7/0x340 kernel/bpf/syscall.c:4702 __sys_bpf+0x5ee/0x8a0 kernel/bpf/syscall.c:6224 __do_sys_bpf kernel/bpf/syscall.c:6319 [inline] __se_sys_bpf kernel/bpf/syscall.c:6317 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6317 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f537358f749 RSP: 002b:00007f53744d8038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f53737e5fa0 RCX: 00007f537358f749 RDX: 0000000000000048 RSI: 0000200000000600 RDI: 000000000000000a RBP: 00007f5373613f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f53737e6038 R14: 00007f53737e5fa0 R15: 00007fff95a4d0c8 rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g109797 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=87852 rcu: rcu_preempt kthread starved for 10500 jiffies! g109797 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:27640 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5282 [inline] __schedule+0x14ed/0x5040 kernel/sched/core.c:6894 __schedule_loop kernel/sched/core.c:6976 [inline] schedule+0x165/0x360 kernel/sched/core.c:6991 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x11b0 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x9b/0x2d0 kernel/rcu/tree.c:2297 kthread+0x389/0x480 kernel/kthread.c:467 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 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: 20047 Comm: syz.9.3582 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:146 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:153 [inline] RIP: 0010:lock_release+0x26e/0x3b0 kernel/locking/lockdep.c:5892 Code: e8 17 2f 00 00 48 8b 5c 24 08 48 c7 c7 c0 45 b8 8d e8 c6 86 bf 09 b8 ff ff ff ff 65 0f c1 05 d9 ae 03 11 83 f8 01 75 2e 9c 58 00 02 00 00 75 42 f7 c3 00 02 00 00 75 47 65 48 8b 05 2b 69 03 RSP: 0018:ffffc90000a08cc0 EFLAGS: 00000046 RAX: 0000000000000046 RBX: 0000000000000087 RCX: 0000000080010003 RDX: 0000000000000002 RSI: ffffffff8db845c0 RDI: ffffffff8be08c60 RBP: ffff8880270a47d8 R08: ffffffff8fa25d77 R09: 1ffffffff1f44bae R10: dffffc0000000000 R11: fffffbfff1f44baf R12: 0000000000000002 R13: 0000000000000002 R14: ffff8880b8728298 R15: ffff8880270a3c80 FS: 00007f1e3fd5e6c0(0000) GS:ffff888125d07000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc04aa47f98 CR3: 0000000068f5a000 CR4: 00000000003526f0 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:176 [inline] _raw_spin_unlock_irqrestore+0x1b/0x80 kernel/locking/spinlock.c:194 __run_hrtimer kernel/time/hrtimer.c:1773 [inline] __hrtimer_run_queues+0x408/0xc30 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:194 Code: f7 e8 2d 70 3e f6 f7 c3 00 02 00 00 74 05 e8 30 5d 68 f6 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 04 8b 30 f6 65 8b 05 dd 67 41 07 85 c0 74 18 5b 41 5e e9 01 48 RSP: 0018:ffffc900046973a8 EFLAGS: 00000206 RAX: 0000000000000006 RBX: 0000000000000246 RCX: 0000000080000002 RDX: 0000000000000006 RSI: ffffffff8d9a0b7f RDI: 0000000000000001 RBP: ffffc90004697488 R08: ffffffff8fa25d77 R09: 1ffffffff1f44bae R10: dffffc0000000000 R11: fffffbfff1f44baf R12: ffff8880b87337a8 R13: dffffc0000000000 R14: ffff8880217e88d8 R15: ffffea0001433980 spin_unlock_irqrestore include/linux/spinlock.h:410 [inline] unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1500 [inline] folio_batch_move_lru+0x37e/0x420 mm/swap.c:178 __folio_batch_add_and_move+0x512/0xc60 mm/swap.c:196 shmem_alloc_and_add_folio+0xca0/0xf40 mm/shmem.c:2003 shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2539 shmem_fault+0x179/0x390 mm/shmem.c:2740 __do_fault+0x138/0x390 mm/memory.c:5302 do_read_fault mm/memory.c:5737 [inline] do_fault mm/memory.c:5871 [inline] do_pte_missing+0x2206/0x3330 mm/memory.c:4416 handle_pte_fault mm/memory.c:6255 [inline] __handle_mm_fault mm/memory.c:6393 [inline] handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6562 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x1650/0x29f0 mm/gup.c:1428 populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1860 __mm_populate+0x24c/0x380 mm/gup.c:1963 mm_populate include/linux/mm.h:3679 [inline] vm_mmap_pgoff+0x387/0x4d0 mm/util.c:586 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1e3ef8f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1e3fd5e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f1e3f1e6180 RCX: 00007f1e3ef8f749 RDX: 0000000001000002 RSI: 0000000000fbe000 RDI: 0000200000000000 RBP: 00007f1e3f013f91 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000004012831 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1e3f1e6218 R14: 00007f1e3f1e6180 R15: 00007ffca9df4fe8