rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-....: (303 ticks this GP) idle=9cb/1/0x4000000000000002 softirq=15083/15083 fqs=2165 (detected by 1, t=10505 jiffies, g=19805, q=1309) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 14 Comm: ksoftirqd/0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x0/0x80 kernel/kcov.c:301 Code: 28 4d 39 ca 77 22 89 ff 89 f6 4a c7 44 02 08 05 00 00 00 4a 89 7c 02 10 4a 89 74 02 18 4a 89 44 02 20 48 ff c1 48 89 0a c3 90 <48> 8b 04 24 65 48 8b 0d c4 9f 8a 7e 65 8b 15 c5 9f 8a 7e 81 e2 00 RSP: 0018:ffffc90000d36b30 EFLAGS: 00000046 RAX: 1ffff11017206a4a RBX: ffff8880b90351c8 RCX: ffff88813fea9dc0 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffc90000d36ca0 R10: fffff520001a6d9b R11: 1ffff920001a6d94 R12: dffffc0000000000 R13: ffffc90000d36d06 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f260b9c3f98 CR3: 000000005e9bf000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: user_mode arch/x86/include/asm/ptrace.h:136 [inline] perf_misc_flags+0x13f/0x1b0 arch/x86/events/core.c:2970 perf_prepare_sample+0x132/0x1cb0 kernel/events/core.c:7622 __perf_event_output kernel/events/core.c:7802 [inline] perf_event_output_forward+0x146/0x280 kernel/events/core.c:7822 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515 perf_swevent_overflow kernel/events/core.c:9591 [inline] perf_swevent_event+0x4ad/0x530 kernel/events/core.c:9629 perf_tp_event+0x32c/0xb50 kernel/events/core.c:10047 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021 perf_trace_preemptirq_template+0x2be/0x380 include/trace/events/preemptirq.h:14 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674 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 ed 11 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b RSP: 0018:ffffc90000d37300 EFLAGS: 00000206 RAX: c26a1b3d29519f00 RBX: 1ffff920001a6e64 RCX: c26a1b3d29519f00 RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800 RBP: ffffc90000d373e0 R08: dffffc0000000000 R09: ffffed1017207662 R10: ffffed1017207662 R11: 1ffff11017207661 R12: ffffffff8c120c00 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:772 [inline] netif_receive_skb_list_internal+0x93a/0xb90 net/core/dev.c:5760 gro_normal_list net/core/dev.c:5913 [inline] gro_normal_one net/core/dev.c:5926 [inline] napi_gro_complete+0x26b/0x630 net/core/dev.c:5962 dev_gro_receive+0x194f/0x20b0 net/core/dev.c:6188 napi_gro_receive+0x31d/0xa60 net/core/dev.c:6293 receive_buf+0x3793/0x5780 drivers/net/virtio_net.c:1240 virtnet_receive drivers/net/virtio_net.c:1504 [inline] virtnet_poll+0x546/0xef0 drivers/net/virtio_net.c:1617 __napi_poll+0xc0/0x430 net/core/dev.c:7075 napi_poll net/core/dev.c:7142 [inline] net_rx_action+0x4a8/0x9c0 net/core/dev.c:7232 handle_softirqs+0x328/0x820 kernel/softirq.c:576 run_ksoftirqd+0x98/0xf0 kernel/softirq.c:943 smpboot_thread_fn+0x4f6/0x970 kernel/smpboot.c:164 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287