rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5832/1:b..l rcu: (detected by 0, t=10502 jiffies, g=8721, q=252 ncpus=2) task:syz-executor190 state:R running task stack:25520 pid:5832 tgid:5832 ppid:5831 task_flags:0x400040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5257 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6864 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7191 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x16c/0x340 kernel/locking/lockdep.c:5872 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 d4 e8 da 10 <48> 3b 44 24 58 0f 85 e5 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000421eb38 EFLAGS: 00000206 RAX: 63ecd11f51b1f900 RBX: 0000000000000000 RCX: 63ecd11f51b1f900 RDX: 000000000613a49c RSI: ffffffff8d944207 RDI: ffffffff8bbf77e0 RBP: ffffffff81742f85 R08: ffffffff81742f85 R09: ffffffff8df3d820 R10: ffffc9000421ecf8 R11: ffffffff81ad8e70 R12: 0000000000000002 R13: ffffffff8df3d820 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 mm/page_owner.c:165 __set_page_owner+0x8d/0x4c0 mm/page_owner.c:341 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3b0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xf2b/0x1960 mm/slub.c:4651 __slab_alloc+0x65/0x100 mm/slub.c:4774 __slab_alloc_node mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:5246 [inline] __do_kmalloc_node mm/slub.c:5651 [inline] __kmalloc_noprof+0x47d/0x7f0 mm/slub.c:5664 kmalloc_noprof include/linux/slab.h:961 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x1c1/0x3b0 security/tomoyo/file.c:771 security_file_open+0xb1/0x270 security/security.c:2636 do_dentry_open+0x34e/0x1420 fs/open.c:939 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:4597 [inline] path_openat+0x33ce/0x3d90 fs/namei.c:4756 do_filp_open+0x1fa/0x410 fs/namei.c:4783 do_sys_openat2+0x121/0x200 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe15a2dede9 RSP: 002b:00007fffebefbe88 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe15a2dede9 RDX: 0000000000000002 RSI: 0000200000000c00 RDI: ffffffffffffff9c RBP: 00000000000f4240 R08: 0000000000000000 R09: 00000000000000a0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fffebefc0a8 R14: 00007fffebefbeb0 R15: 00007fffebefbea0 rcu: rcu_preempt kthread starved for 10462 jiffies! g8721 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:27224 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5257 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6864 __schedule_loop kernel/sched/core.c:6946 [inline] schedule+0x165/0x360 kernel/sched/core.c:6961 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 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: CPU: 0 UID: 0 PID: 5827 Comm: syz-executor190 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:__local_bh_disable_ip+0xdc/0x190 kernel/softirq.c:393 Code: 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 0f 85 a4 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 65 8b 05 74 e3 f3 10 <25> ff ff ff 7f 39 d8 75 42 48 8b 5d 08 48 89 df e8 bf 88 19 00 85 RSP: 0018:ffffc9000416f880 EFLAGS: 00000206 RAX: 0000000080000200 RBX: 0000000000000200 RCX: 0000000058cbdf50 RDX: 0000000000000000 RSI: 0000000000000200 RDI: ffffffff89778022 RBP: ffffc9000416f930 R08: ffff88807de50007 R09: 1ffff1100fbca000 R10: dffffc0000000000 R11: ffffed100fbca001 R12: 1ffff9200082df10 R13: ffffc90000aae048 R14: 0000000000000246 R15: dffffc0000000000 FS: 0000555580187380(0000) GS:ffff888125e8b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000c00 CR3: 000000007385a000 CR4: 00000000003526f0 Call Trace: local_bh_disable include/linux/bottom_half.h:20 [inline] bpf_test_run+0x237/0x7a0 net/bpf/test_run.c:417 bpf_prog_test_run_skb+0xd67/0x1d50 net/bpf/test_run.c:1158 bpf_prog_test_run+0x2c7/0x340 kernel/bpf/syscall.c:4712 __sys_bpf+0x562/0x860 kernel/bpf/syscall.c:6191 __do_sys_bpf kernel/bpf/syscall.c:6283 [inline] __se_sys_bpf kernel/bpf/syscall.c:6281 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6281 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe15a2dede9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fffebefbe88 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 785558656a9e3876 RCX: 00007fe15a2dede9 RDX: 000000000000009f RSI: 0000200000000900 RDI: 000000000000000a RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000000a0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000