rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5838/1:b..l (detected by 0, t=10505 jiffies, g=230477, q=658 ncpus=2) task:syz.6.9440 state:R running task stack:23344 pid:5838 ppid:26190 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6731 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6755 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __local_bh_enable_ip+0x147/0x1c0 kernel/softirq.c:428 local_bh_enable include/linux/bottom_half.h:33 [inline] xdp_test_run_batch net/bpf/test_run.c:340 [inline] bpf_test_run_xdp_live+0x1834/0x1a90 net/bpf/test_run.c:362 bpf_prog_test_run_xdp+0x736/0xf10 net/bpf/test_run.c:1412 bpf_prog_test_run+0x31e/0x390 kernel/bpf/syscall.c:3695 __sys_bpf+0x62b/0x780 kernel/bpf/syscall.c:5048 __do_sys_bpf kernel/bpf/syscall.c:5134 [inline] __se_sys_bpf kernel/bpf/syscall.c:5132 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5132 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: 0033:0x7fc42a59c629 RSP: 002b:00007fc42b3db028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fc42a815fa0 RCX: 00007fc42a59c629 RDX: 0000000000000048 RSI: 0000200000000600 RDI: 000000000000000a RBP: 00007fc42a632b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc42a816038 R14: 00007fc42a815fa0 R15: 00007ffd97f56c88 rcu: rcu_preempt kthread timer wakeup didn't happen for 10486 jiffies! g230477 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=135403 rcu: rcu_preempt kthread starved for 10487 jiffies! g230477 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:27408 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5840 Comm: syz.5.9441 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:lockdep_hardirqs_on+0x4a/0x140 kernel/locking/lockdep.c:4350 Code: 5c f3 03 00 0f 84 90 00 00 00 65 8b 05 77 c9 d5 75 a9 00 00 f0 00 75 4d 65 8b 05 e1 d3 d5 75 85 c0 75 77 65 8b 05 86 d0 d5 75 <85> c0 75 6c 83 3d 4b 1b 93 0c 00 75 2e 48 c7 04 24 00 00 00 00 9c RSP: 0018:ffffc900001e0d30 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff888063629dc0 RCX: ac4fa52a71f9c200 RDX: dffffc0000000000 RSI: ffffffff8a8c23a0 RDI: ffffffff8a400e86 RBP: 0000000000000000 R08: ffff8880b8f3580b R09: 1ffff110171e6b01 R10: dffffc0000000000 R11: ffffed10171e6b02 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f2c5a3f66c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc42b3bad58 CR3: 0000000077516000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000008d24 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728 RIP: 0010:variable_ffs arch/x86/include/asm/bitops.h:319 [inline] RIP: 0010:handle_softirqs+0x1c8/0x930 kernel/softirq.c:584 Code: 89 7c 24 44 0f b7 db 48 c7 c7 00 08 8b 8a e8 df 51 dd 08 65 66 c7 05 15 37 b4 7e 00 00 e8 b0 74 39 00 fb 49 c7 c6 c0 a0 80 8c <89> 5c 24 4c b8 ff ff ff ff 0f bc 44 24 4c 41 89 c5 41 ff c5 0f 84 RSP: 0018:ffffc900001e0e00 EFLAGS: 00000286 RAX: ac4fa52a71f9c200 RBX: 0000000000000200 RCX: ac4fa52a71f9c200 RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0de0 RBP: ffffc900001e0f30 R08: ffff8880b8f3580b R09: 1ffff110171e6b01 R10: dffffc0000000000 R11: ffffed10171e6b02 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff8c80a0c0 R15: 000000000000000a __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:__rcu_read_unlock+0x36/0xd0 kernel/rcu/tree_plugin.h:425 Code: 00 00 00 00 fc ff df 65 48 8b 3d b5 32 95 7e 48 8d 9f 3c 04 00 00 49 89 dc 49 c1 ec 03 43 0f b6 04 3c 84 c0 75 48 ff 0b 75 1d <4c> 8d b7 40 04 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 38 84 c0 75 RSP: 0018:ffffc90005567b08 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff88806362a1fc RCX: 0000000000080000 RDX: ffffc90014cc1000 RSI: 000000000001f15e RDI: ffff888063629dc0 RBP: dffffc0000000000 R08: ffff88801ad201ff R09: 1ffff110035a403f R10: dffffc0000000000 R11: ffffed10035a4040 R12: 1ffff1100c6c543f R13: 0000000000000003 R14: 0000000000000000 R15: dffffc0000000000 rcu_read_unlock include/linux/rcupdate.h:823 [inline] page_ext_put+0x91/0xb0 mm/page_ext.c:182 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1486 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508 free_slab mm/slub.c:2036 [inline] discard_slab mm/slub.c:2042 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2591 put_cpu_partial+0x17c/0x250 mm/slub.c:2667 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc_lru+0x11a/0x2e0 mm/slub.c:3390 alloc_inode_sb include/linux/fs.h:3245 [inline] sock_alloc_inode+0x24/0xc0 net/socket.c:306 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x5f/0x1c0 fs/inode.c:1063 sock_alloc net/socket.c:631 [inline] __sock_create+0x129/0x940 net/socket.c:1513 sock_create net/socket.c:1605 [inline] __sys_socket_create net/socket.c:1642 [inline] __sys_socket+0xc4/0x190 net/socket.c:1670 __do_sys_socket net/socket.c:1683 [inline] __se_sys_socket net/socket.c:1681 [inline] __x64_sys_socket+0x76/0x80 net/socket.c:1681 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: 0033:0x7f2c5c19c629 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2c5a3f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 00007f2c5c415fa0 RCX: 00007f2c5c19c629 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000011 RBP: 00007f2c5c232b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2c5c416038 R14: 00007f2c5c415fa0 R15: 00007ffe957ab258