rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P14195/1:b..l rcu: (detected by 0, t=10502 jiffies, g=49597, q=204 ncpus=2) task:syz.1.2230 state:R running task stack:26824 pid:14195 tgid:14192 ppid:5819 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5248 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6855 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7182 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:rcu_lock_acquire include/linux/rcupdate.h:331 [inline] RIP: 0010:rcu_read_lock include/linux/rcupdate.h:867 [inline] RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1195 [inline] RIP: 0010:unwind_next_frame+0xae/0x20a0 arch/x86/kernel/unwind_orc.c:479 Code: 48 89 04 24 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 3e 18 00 00 49 8b 45 38 48 89 44 24 10 e8 12 fa 35 00 <31> d2 45 31 c9 45 31 c0 48 8d 05 00 00 00 00 50 b9 02 00 00 00 31 RSP: 0018:ffffc9000b8f7420 EFLAGS: 00000293 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffc9000b8f7578 RDX: 0000000000000000 RSI: ffff888022fec980 RDI: ffff888022fece04 RBP: ffffc9000b8f7528 R08: 0000000000000001 R09: 0000000000000000 R10: ffffc9000b8f74e0 R11: 00000000f9abc992 R12: fffff5200171ee9e R13: ffffc9000b8f74e0 R14: ffffc9000b8f74e0 R15: ffffc9000b8f74e8 __unwind_start+0x45f/0x7f0 arch/x86/kernel/unwind_orc.c:758 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0x73/0x100 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 save_stack+0x160/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x84/0x1a0 mm/page_owner.c:311 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2901 discard_slab mm/slub.c:3330 [inline] __put_partials+0x130/0x170 mm/slub.c:3876 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4978 [inline] slab_alloc_node mm/slub.c:5288 [inline] kmem_cache_alloc_lru_noprof+0x254/0x720 mm/slub.c:5307 __d_alloc+0x35/0xa80 fs/dcache.c:1691 d_alloc_pseudo+0x1c/0xc0 fs/dcache.c:1822 alloc_path_pseudo fs/file_table.c:363 [inline] alloc_file_pseudo+0xcf/0x230 fs/file_table.c:379 __anon_inode_getfile+0xe8/0x280 fs/anon_inodes.c:166 __anon_inode_getfd+0x5c/0x150 fs/anon_inodes.c:283 bpf_map_new_fd kernel/bpf/syscall.c:1191 [inline] bpf_map_new_fd kernel/bpf/syscall.c:1183 [inline] map_create+0x1740/0x29f0 kernel/bpf/syscall.c:1602 __sys_bpf+0x3d9d/0x4980 kernel/bpf/syscall.c:6131 __do_sys_bpf kernel/bpf/syscall.c:6259 [inline] __se_sys_bpf kernel/bpf/syscall.c:6257 [inline] __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:6257 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f34c1b8f749 RSP: 002b:00007f34c29aa038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f34c1de6180 RCX: 00007f34c1b8f749 RDX: 0000000000000048 RSI: 00002000000007c0 RDI: 0000000000000000 RBP: 00007f34c1c13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f34c1de6218 R14: 00007f34c1de6180 R15: 00007ffc5cfc5988 rcu: rcu_preempt kthread starved for 10214 jiffies! g49597 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:27960 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5248 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6855 __schedule_loop kernel/sched/core.c:6937 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6952 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 76 76 02 e9 d3 2f 03 00 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 13 d3 2b 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197de8 EFLAGS: 000002c2 RAX: 000000000383d27f RBX: 0000000000000001 RCX: ffffffff8b5e86f9 RDX: 0000000000000000 RSI: ffffffff8daa3473 RDI: ffffffff8bf1d300 RBP: ffffed1003b50498 R08: 0000000000000001 R09: ffffed10170a672d R10: ffff8880b853396b R11: 00000000ffffffff R12: 0000000000000001 R13: ffff88801da824c0 R14: ffffffff9085ced0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124a9c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff7e215f28 CR3: 000000005ba1d000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x38d/0x510 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x148