rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7680/1:b..l (detected by 1, t=10502 jiffies, g=31385, q=2180 ncpus=2) task:syz.1.956 state:R running task stack:23472 pid:7680 ppid:4268 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline] RIP: 0010:__local_bh_enable_ip+0x13e/0x1c0 kernel/softirq.c:428 Code: 8a e8 46 b6 dd 08 65 66 8b 05 7e 3b b4 7e 66 85 c0 75 54 bf 01 00 00 00 e8 6f 85 09 00 e8 9a 76 39 00 fb 65 8b 05 2a 0a b3 7e <85> c0 75 05 e8 79 1e b1 ff 48 c7 04 24 0e 36 e0 45 4b c7 04 37 00 RSP: 0018:ffffc900047c76a0 EFLAGS: 00000286 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 4293b875d0e81e00 RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0f60 RBP: ffffc900047c7730 R08: ffff8880b8e3580b R09: 1ffff110171c6b01 R10: dffffc0000000000 R11: ffffed10171c6b02 R12: ffffffff88314b2b R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920008f8ed4 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:861 [inline] __dev_queue_xmit+0x1cd2/0x37c0 net/core/dev.c:4399 dev_queue_xmit include/linux/netdevice.h:3051 [inline] __bpf_tx_skb net/core/filter.c:2134 [inline] __bpf_redirect_common net/core/filter.c:2182 [inline] __bpf_redirect+0xbdf/0x1180 net/core/filter.c:2189 ____bpf_clone_redirect net/core/filter.c:2473 [inline] bpf_clone_redirect+0x30b/0x4a0 net/core/filter.c:2436 bpf_prog_ef75413035540f6e+0x19/0x1d bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_test_run+0x2b6/0x830 net/bpf/test_run.c:402 bpf_prog_test_run_skb+0xaa6/0x12a0 net/bpf/test_run.c:1191 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: 0033:0x7f171099c799 RSP: 002b:00007f1711808028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f1710c15fa0 RCX: 00007f171099c799 RDX: 0000000000000050 RSI: 00002000000003c0 RDI: 000000000000000a RBP: 00007f1710a32c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1710c16038 R14: 00007f1710c15fa0 R15: 00007ffc6053b338 rcu: rcu_preempt kthread timer wakeup didn't happen for 10433 jiffies! g31385 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=17445 rcu: rcu_preempt kthread starved for 10434 jiffies! g31385 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27352 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7679 Comm: syz.1.956 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:215 Code: 00 00 00 00 00 90 53 48 89 fb e8 17 00 00 00 48 8b 3d f0 66 9d 0c 48 89 de 5b e9 77 21 50 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d 84 fc 7f 7e 65 8b 15 85 fc 7f 7e 81 e2 00 01 ff 00 74 RSP: 0018:ffffc900047876f8 EFLAGS: 00000046 RAX: ffffffff813a0dfb RBX: 00000000b8e3b9f0 RCX: ffff88802ef8bb80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffff8880b8e3b9fb R09: 1ffff110171c773f R10: dffffc0000000000 R11: ffffed10171c7740 R12: 0000000000000000 R13: dffffc0000000001 R14: 000000000000002e R15: 0000000000000000 FS: 0000555594fb4500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2c8d0e CR3: 00000000569ab000 CR4: 00000000003506f0 DR0: fffffffffffffffc DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __virt_addr_valid+0xcb/0x540 arch/x86/mm/physaddr.c:61 kasan_addr_to_slab+0x9/0xc0 mm/kasan/common.c:36 __kasan_record_aux_stack+0xf/0xc0 mm/kasan/generic.c:471 irq_work_queue_on+0x10f/0x260 kernel/irq_work.c:140 rcu_read_unlock_special+0x3c9/0x510 kernel/rcu/tree_plugin.h:678 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426 rcu_read_unlock include/linux/rcupdate.h:823 [inline] trace_call_bpf+0x5bb/0x6b0 kernel/trace/bpf_trace.c:137 perf_trace_run_bpf_submit+0x79/0x1c0 kernel/events/core.c:9997 perf_trace_preemptirq_template+0x268/0x320 include/trace/events/preemptirq.h:14 trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40 trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728 RIP: 0010:rcu_read_unlock_special+0x7f/0x510 kernel/rcu/tree_plugin.h:685 Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 e2 33 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08 RSP: 0018:ffffc90004787c00 EFLAGS: 00000206 RAX: 6967bacf32ad1800 RBX: 1ffff920008f0f88 RCX: 6967bacf32ad1800 RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0f60 RBP: ffffc90004787cf8 R08: ffffffff90af624f R09: 1ffffffff215ec49 R10: dffffc0000000000 R11: fffffbfff215ec4a R12: 0000000000000246 R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8cb32c58 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426 rcu_read_unlock+0x85/0xa0 include/linux/rcupdate.h:823 dput+0xe2/0x1d0 fs/dcache.c:911 __fput+0x5e0/0x920 fs/file_table.c:328 task_work_run+0x1d0/0x260 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f171099c799 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:00007ffc6053b498 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f1710c17da0 RCX: 00007f171099c799 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f1710c17da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007f1710c17cb0 R11: 0000000000000246 R12: 0000000000047441 R13: 00007f1710c1609c R14: 0000000000047212 R15: 00007f1710c16090