rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=6eec/1/0x4000000000000000 softirq=59434/59434 fqs=0 rcu: (detected by 0, t=10502 jiffies, g=50189, q=93 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 13802 Comm: syz.5.1713 Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210 Code: 7e 60 e8 a3 ff ff ff 31 c0 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 65 48 8b 15 d4 c2 69 7e 65 8b 05 d5 c2 69 7e a9 00 01 RSP: 0018:ffffc90000a18dc8 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff88803340a340 RCX: ffffffff8b260ed0 RDX: 1ffff110170e596b RSI: ffffffff8b260ede RDI: 0000000000000006 RBP: ffff8880b872cb50 R08: 0000000000000006 R09: 0000000000000001 R10: ffff88803340a340 R11: 0000000000000001 R12: ffff8880b872cb58 R13: 0000000000000000 R14: ffff8880b872ca00 R15: 0000000000000000 FS: 00007f9a951d16c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b3021fffc CR3: 0000000077304000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rb_erase_cached include/linux/rbtree.h:124 [inline] timerqueue_del+0xd0/0x150 lib/timerqueue.c:57 __remove_hrtimer+0x99/0x290 kernel/time/hrtimer.c:1109 __run_hrtimer kernel/time/hrtimer.c:1719 [inline] __hrtimer_run_queues+0x50b/0xae0 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:write_comp_data+0x8b/0x90 kernel/kcov.c:272 Code: 00 00 4a 8d 34 dd 28 00 00 00 48 39 f2 72 1b 48 83 c7 01 48 89 38 4c 89 44 30 e0 4c 89 4c 30 e8 4c 89 54 30 f0 4a 89 4c d8 20 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 RSP: 0018:ffffc9000c27fa30 EFLAGS: 00000297 RAX: 0000000000000002 RBX: ffffffff8bd19d40 RCX: ffffffff81e28ac2 RDX: ffff88805d408000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00000000000000a2 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffffc9000c27faa8 R14: ffffc9000c27fb90 R15: ffffc9000c27faa8 __might_fault+0x62/0x190 mm/memory.c:6746 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x29/0xd0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] copy_msghdr_from_user+0x99/0x160 net/socket.c:2513 recvmsg_copy_msghdr net/socket.c:2769 [inline] ___sys_recvmsg+0xdc/0x1a0 net/socket.c:2841 do_recvmmsg+0x2f8/0x740 net/socket.c:2940 __sys_recvmmsg net/socket.c:3014 [inline] __do_sys_recvmmsg net/socket.c:3037 [inline] __se_sys_recvmmsg net/socket.c:3030 [inline] __x64_sys_recvmmsg+0x239/0x290 net/socket.c:3030 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9a94385d29 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:00007f9a951d1038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f9a94576080 RCX: 00007f9a94385d29 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000005 RBP: 00007f9a94401b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9a94576080 R15: 00007fffd6599a98 rcu: rcu_preempt kthread starved for 10502 jiffies! g50189 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:27488 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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: CPU: 0 UID: 0 PID: 13803 Comm: syz.5.1713 Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x47c/0x1300 kernel/smp.c:884 Code: ba 0e 0c 00 f3 90 41 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 a7 0c 00 00 8b 43 08 31 ff 83 e0 01 41 89 c5 89 c6 e8 d4 10 0c 00 <45> 85 ed 75 d0 e8 8a 0e 0c 00 e8 85 0e 0c 00 44 8b 6c 24 20 bf 07 RSP: 0018:ffffc90002fd76c8 EFLAGS: 00000297 RAX: 0000000000000002 RBX: ffff8880b8744a40 RCX: ffffffff818e078c RDX: ffff8880307d0000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000004 R12: ffffed10170e8949 R13: 0000000000000001 R14: ffff8880b8744a48 R15: ffff8880b863fe40 FS: 00007f9a951b06c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9a951aff98 CR3: 0000000077304000 CR4: 00000000003526f0 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2114 [inline] text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_flush arch/x86/kernel/alternative.c:2512 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2522 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:920 static_key_slow_inc_cpuslocked kernel/jump_label.c:168 [inline] static_key_slow_inc_cpuslocked+0x82/0x120 kernel/jump_label.c:151 static_key_slow_inc+0x1a/0x30 kernel/jump_label.c:191 kvm_create_lapic+0x39c/0x500 arch/x86/kvm/lapic.c:2894 kvm_arch_vcpu_create+0x24c/0xae0 arch/x86/kvm/x86.c:12248 kvm_vm_ioctl_create_vcpu virt/kvm/kvm_main.c:4106 [inline] kvm_vm_ioctl+0xf93/0x3df0 virt/kvm/kvm_main.c:5019 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9a94385d29 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:00007f9a951b0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f9a94576160 RCX: 00007f9a94385d29 RDX: 0000000000000000 RSI: 000000000000ae41 RDI: 0000000000000004 RBP: 00007f9a94401b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9a94576160 R15: 00007fffd6599a98