rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (10500 ticks this GP) idle=b6fc/1/0x4000000000000000 softirq=19048/1909894 fqs=4784 rcu: hardirqs softirqs csw/system rcu: number: 1 940152 0 rcu: cputime: 1082 50163 1247 ==> 52490(ms) rcu: (t=10500 jiffies g=12009 q=3799 ncpus=2) CPU: 0 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted 6.15.0-rc4-syzkaller-g7220eabff8cb #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:rb_read_data_buffer+0x423/0x580 kernel/trace/ring_buffer.c:-1 Code: 48 89 e8 4c 21 e8 74 52 49 09 c6 4c 89 f7 48 89 ee e8 01 34 fc ff 49 39 ee 4d 89 e5 72 5f e8 94 31 fc ff eb 3d e8 8d 31 fc ff <4d> 89 e5 ff 04 24 41 c1 ee 05 49 01 ee 48 89 df e8 18 10 fe ff 41 RSP: 0018:ffffc900000073d0 EFLAGS: 00000246 RAX: ffffffff81c38af2 RBX: ffff88801a086240 RCX: ffff88801b688000 RDX: 0000000000000100 RSI: ffffffff8df90d30 RDI: 0000000000000004 RBP: 000000332749611f R08: ffff88801b688000 R09: 0000000000000020 R10: 000000000000001f R11: 0000000000000100 R12: ffff88801a086010 R13: 0000000000000004 R14: 000000000008be44 R15: 0000000000000230 FS: 0000000000000000(0000) GS:ffff8881260cc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b30109ff8 CR3: 0000000011050000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: check_buffer+0x28a/0x750 kernel/trace/ring_buffer.c:4297 __rb_reserve_next+0x592/0xdb0 kernel/trace/ring_buffer.c:4396 rb_reserve_next_event kernel/trace/ring_buffer.c:4533 [inline] ring_buffer_lock_reserve+0xbb5/0x1010 kernel/trace/ring_buffer.c:4592 __trace_buffer_lock_reserve kernel/trace/trace.c:1028 [inline] trace_event_buffer_lock_reserve+0x1d0/0x6f0 kernel/trace/trace.c:2742 trace_event_buffer_reserve+0x2a6/0x3d0 kernel/trace/trace_events.c:661 do_trace_event_raw_event_bpf_trace_printk kernel/trace/bpf_trace.h:11 [inline] trace_event_raw_event_bpf_trace_printk+0x100/0x260 kernel/trace/bpf_trace.h:11 __do_trace_bpf_trace_printk kernel/trace/bpf_trace.h:11 [inline] trace_bpf_trace_printk+0x170/0x1d0 kernel/trace/bpf_trace.h:11 ____bpf_trace_printk kernel/trace/bpf_trace.c:380 [inline] bpf_trace_printk+0x11e/0x190 kernel/trace/bpf_trace.c:363 bpf_prog_9e1c00255e17e72e+0x39/0x3b bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline] __bpf_prog_run include/linux/filter.h:709 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2258 [inline] bpf_trace_run1+0x3fd/0x4b0 kernel/trace/bpf_trace.c:2298 __bpf_trace_rcu_utilization+0xa1/0xf0 include/trace/events/rcu.h:27 __traceiter_rcu_utilization+0x77/0xb0 include/trace/events/rcu.h:27 __do_trace_rcu_utilization include/trace/events/rcu.h:27 [inline] trace_rcu_utilization+0x1ad/0x1d0 include/trace/events/rcu.h:27 rcu_core+0x1336/0x1710 kernel/rcu/tree.c:2832 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 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+0x87/0x4c0 kernel/rcu/tree_plugin.h:694 Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 e2 a3 cd 10 41 f7 c6 00 00 f0 00 74 49 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b RSP: 0018:ffffc90000127380 EFLAGS: 00000206 RAX: 78eb23b1e42d9900 RBX: 1ffff92000024e78 RCX: 78eb23b1e42d9900 RDX: 0000000000000006 RSI: ffffffff8d74a4de RDI: ffffffff8bc1d020 RBP: ffffc90000127478 R08: ffffffff8f7ed277 R09: 1ffffffff1efda4e R10: dffffc0000000000 R11: fffffbfff1efda4f R12: ffffffff8df40c00 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 __rcu_read_unlock+0x84/0xe0 kernel/rcu/tree_plugin.h:438 rcu_read_unlock include/linux/rcupdate.h:873 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x19ae/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2398 [inline] slab_free mm/slub.c:4656 [inline] kfree+0x193/0x440 mm/slub.c:4855 skb_kfree_head net/core/skbuff.c:1058 [inline] skb_free_head net/core/skbuff.c:1070 [inline] skb_release_data+0x69a/0x890 net/core/skbuff.c:1097 skb_release_all net/core/skbuff.c:1162 [inline] __kfree_skb net/core/skbuff.c:1176 [inline] consume_skb+0x9e/0xf0 net/core/skbuff.c:1408 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] nsim_dev_trap_report_work+0x7cf/0xb80 drivers/net/netdevsim/dev.c:851 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245