rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8800/1:b..l rcu: (detected by 1, t=10502 jiffies, g=30801, q=392 ncpus=2) task:syz.1.690 state:R running task stack:22520 pid:8800 tgid:8796 ppid:5858 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6935 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6959 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0x179/0x200 kernel/softirq.c:389 local_bh_enable include/linux/bottom_half.h:33 [inline] bpf_test_run+0x56b/0xa90 net/bpf/test_run.c:437 bpf_prog_test_run_skb+0xca2/0x1820 net/bpf/test_run.c:1095 bpf_prog_test_run+0x2e4/0x360 kernel/bpf/syscall.c:4402 __sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5808 __do_sys_bpf kernel/bpf/syscall.c:5897 [inline] __se_sys_bpf kernel/bpf/syscall.c:5895 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5895 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f372b37e819 RSP: 002b:00007f372c12e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f372b536080 RCX: 00007f372b37e819 RDX: 0000000000000050 RSI: 0000000020000380 RDI: 000000000000000a RBP: 00007f372b3f175e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f372b536080 R15: 00007ffe320cacb8 rcu: rcu_preempt kthread starved for 10457 jiffies! g30801 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:25376 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8786 Comm: syz.3.688 Not tainted 6.12.0-syzkaller-09087-g3448ad23b34e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__sanitizer_cov_trace_switch+0x98/0x120 kernel/kcov.c:351 Code: 00 41 b8 05 00 00 00 4d 85 d2 0f 84 8b 00 00 00 4c 8b 4c 24 20 65 4c 8b 1c 25 c0 d4 03 00 31 d2 eb 08 48 ff c2 49 39 d2 74 71 <4c> 8b 74 d6 10 65 8b 05 94 ee 6d 7e 25 00 01 ff 00 74 11 3d 00 01 RSP: 0018:ffffc90000007370 EFLAGS: 00000212 RAX: 0000000000000100 RBX: 0000000000000004 RCX: dffffc0000000000 RDX: 0000000000000018 RSI: ffffffff8e9927d0 RDI: 0000000000000004 RBP: 0000000000000003 R08: 0000000000000005 R09: ffffffff8199e443 R10: 0000000000000020 R11: ffff8880310ebc00 R12: 0000005034a36312 R13: 000000000000003c R14: 0000000000000017 R15: ffff88801ac8604c FS: 0000555585c95500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b3150aff8 CR3: 000000005649a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rb_read_data_buffer+0x103/0x520 kernel/trace/ring_buffer.c:1753 check_buffer+0x35e/0x850 kernel/trace/ring_buffer.c:4221 __rb_reserve_next kernel/trace/ring_buffer.c:4320 [inline] rb_reserve_next_event kernel/trace/ring_buffer.c:4452 [inline] ring_buffer_lock_reserve+0x12a9/0x21c0 kernel/trace/ring_buffer.c:4511 __trace_buffer_lock_reserve kernel/trace/trace.c:1020 [inline] trace_event_buffer_lock_reserve+0x2ab/0x6a0 kernel/trace/trace.c:2746 trace_event_buffer_reserve+0x2b7/0x3f0 kernel/trace/trace_events.c:515 do_trace_event_raw_event_bpf_trace_printk kernel/trace/bpf_trace.h:11 [inline] trace_event_raw_event_bpf_trace_printk+0x102/0x260 kernel/trace/bpf_trace.h:11 trace_bpf_trace_printk+0x186/0x1f0 kernel/trace/bpf_trace.h:11 ____bpf_trace_printk kernel/trace/bpf_trace.c:391 [inline] bpf_trace_printk+0x1bf/0x230 kernel/trace/bpf_trace.c:374 bpf_prog_0605f9f479290f07+0x38/0x3c bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline] __bpf_prog_run include/linux/filter.h:701 [inline] bpf_prog_run include/linux/filter.h:708 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2351 [inline] bpf_trace_run1+0x2ca/0x520 kernel/trace/bpf_trace.c:2391 trace_rcu_utilization+0x1b4/0x1e0 include/trace/events/rcu.h:27 rcu_core+0x1161/0x17a0 kernel/rcu/tree.c:2831 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:655 irq_exit_rcu+0x9/0x30 kernel/softirq.c:671 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0xa3/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738 RIP: 0010:rcu_read_unlock_special+0x88/0x570 kernel/rcu/tree_plugin.h:693 Code: f1 f1 f1 00 f2 f2 f2 49 89 04 14 66 41 c7 44 14 09 f3 f3 41 c6 44 14 0b f3 65 44 8b 3d 19 7b 87 7e 41 f7 c7 00 00 f0 00 74 49 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 22 00 00 00 00 66 42 c7 44 22 RSP: 0018:ffffc90003117c20 EFLAGS: 00000206 RAX: d63ec450bc6a1400 RBX: 1ffff92000622f8c RCX: ffffffff81718eba RDX: dffffc0000000000 RSI: ffffffff8c0ad8a0 RDI: ffffffff8c6154a0 RBP: ffffc90003117cf8 R08: ffffffff9431f8c7 R09: 1ffffffff2863f18 R10: dffffc0000000000 R11: fffffbfff2863f19 R12: 1ffff92000622f88 R13: ffff8880310ec060 R14: ffffc90003117c60 R15: 0000000000000000 __rcu_read_unlock+0xa1/0x110 kernel/rcu/tree_plugin.h:437 dput+0x197/0x2b0 fs/dcache.c:866 __fput+0x5ba/0xa50 fs/file_table.c:458 task_work_run+0x24f/0x310 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f88f1f7e819 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:00007ffd38a90708 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f88f2137ba0 RCX: 00007f88f1f7e819 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f88f2137ba0 R08: 0000000000014034 R09: 00007ffd38a909ff R10: 00007f88f2137ac0 R11: 0000000000000246 R12: 000000000003a6ee R13: 00007ffd38a90810 R14: 0000000000000032 R15: ffffffffffffffff