rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=b31/1/0x4000000000000000 softirq=23433/23434 fqs=5226 (t=10502 jiffies g=31869 q=2986) NMI backtrace for cpu 1 CPU: 1 PID: 13275 Comm: vhost-13272 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x22d/0x390 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq+0x1e33/0x2bc0 kernel/rcu/tree.c:2597 update_process_times+0x197/0x200 kernel/time/timer.c:1785 tick_sched_handle kernel/time/tick-sched.c:226 [inline] tick_sched_timer+0x27d/0x420 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4cb/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:vhost_iotlb_itree_iter_first drivers/vhost/iotlb.c:19 [inline] RIP: 0010:vhost_iotlb_itree_first+0x8e/0x260 drivers/vhost/iotlb.c:169 Code: 2e fa 49 8b 5d 00 48 89 df 4c 89 fe e8 3b e4 e2 f9 4c 39 fb 73 14 e8 f1 e1 e2 f9 e9 c2 01 00 00 e8 e7 e1 e2 f9 e9 b8 01 00 00 <49> 83 c4 08 4c 89 e0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 RSP: 0018:ffffc90005417a78 EFLAGS: 00000286 RAX: 0000000000000002 RBX: ffffffffffffffff RCX: dffffc0000000000 RDX: ffff88802344d700 RSI: 0000000000000000 RDI: ffffffffffffffff RBP: 000000000000000f R08: ffffffff87a162e5 R09: fffff52000a82f2d R10: fffff52000a82f2d R11: 0000000000000000 R12: ffff888077994480 R13: ffff8880161e7650 R14: ffff8880161e7600 R15: 0000000000000000 iotlb_access_ok+0x172/0x330 drivers/vhost/vhost.c:1336 vq_meta_prefetch+0x9f/0x1d0 drivers/vhost/vhost.c:1366 handle_rx+0x236/0x1430 drivers/vhost/net.c:1140 vhost_worker+0x215/0x340 drivers/vhost/vhost.c:372 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 ---------------- Code disassembly (best guess): 0: 2e fa cs cli 2: 49 8b 5d 00 mov 0x0(%r13),%rbx 6: 48 89 df mov %rbx,%rdi 9: 4c 89 fe mov %r15,%rsi c: e8 3b e4 e2 f9 callq 0xf9e2e44c 11: 4c 39 fb cmp %r15,%rbx 14: 73 14 jae 0x2a 16: e8 f1 e1 e2 f9 callq 0xf9e2e20c 1b: e9 c2 01 00 00 jmpq 0x1e2 20: e8 e7 e1 e2 f9 callq 0xf9e2e20c 25: e9 b8 01 00 00 jmpq 0x1e2 * 2a: 49 83 c4 08 add $0x8,%r12 <-- trapping instruction 2e: 4c 89 e0 mov %r12,%rax 31: 48 c1 e8 03 shr $0x3,%rax 35: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 3c: fc ff df 3f: 80 .byte 0x80