What were you trying to do that didn't work?
Boot a rhel guest on EPYC-Genoa, hotplug vcpu, guest hit soft lockup.

Please provide the package NVR for which bug is seen:
kernel-6.10.0-15.el10.x86_64
qemu-kvm-9.0.0-4.el10
systemd-256-6.el10.x86_64
systemd-udev-256-6.el10.x86_64

How reproducible:
3/3

Steps to reproduce
1. Boot rhel.10.0 guest
2. Hotplug vcpu to the guest

Expected results
Guest works well.

Actual results
Guest hit soft lockup.
024-07-23 05:00:04: [ 24.318797] ACPI: CPU47 has been hot-added
2024-07-23 05:00:04: [ 24.360911] smpboot: Booting Node 0 Processor 47 APIC 0x37
2024-07-23 05:00:04: [ 24.362301] Will online and init hotplugged CPU: 47
2024-07-23 05:00:04: !!!! X64 Exception Type - 0E(#PF - Page-Fault) CPU Apic ID - 00000037 !!!!
2024-07-23 05:00:04: ExceptionData - 0000000000000003 I:0 R:0 U:0 W:1 P:1 PK:0 SS:0 SGX:0
2024-07-23 05:00:04: RIP - 000000007FFC506B, CS - 0000000000000038, RFLAGS - 0000000000010093
2024-07-23 05:00:04: RAX - 0000000000000001, RCX - 000000007FFCBDEB, RDX - 0000000000000000
2024-07-23 05:00:04: RBX - 000000007FFCBDEB, RSP - 000000007FFB7D00, RBP - 000000007FFB7D40
2024-07-23 05:00:04: RSI - 0000000000000000, RDI - 0000000000000001
2024-07-23 05:00:04: R8 - 0000000000000001, R9 - 000000007FFB7D38, R10 - 0000000000000015
2024-07-23 05:00:04: R11 - 0000000000000000, R12 - 0000000000000000, R13 - 0000000000000000
2024-07-23 05:00:04: R14 - 0000000000000000, R15 - 0000000000000000
2024-07-23 05:00:04: DS - 0000000000000020, ES - 0000000000000020, FS - 0000000000000020
2024-07-23 05:00:04: GS - 0000000000000020, SS - 0000000000000020
2024-07-23 05:00:04: CR0 - 0000000080010033, CR2 - 000000007FFCBDEA, CR3 - 000000007FE63000
2024-07-23 05:00:04: CR4 - 0000000000000668, CR8 - 0000000000000001
2024-07-23 05:00:04: DR0 - 0000000000000000, DR1 - 0000000000000000, DR2 - 0000000000000000
2024-07-23 05:00:04: DR3 - 0000000000000000, DR6 - 00000000FFFF0FF0, DR7 - 0000000000000400
2024-07-23 05:00:04: GDTR - 000000007FE911C8 000000000000004F, LDTR - 0000000000000000
2024-07-23 05:00:04: IDTR - 000000007FE97000 00000000000001FF, TR - 0000000000000040
2024-07-23 05:00:04: FXSAVE_STATE - 000000007FFB2C60
2024-07-23 05:00:42: [
2024-07-23 05:00:44: 60.962320] watchdog: BUG: soft lockup - CPU#3
2024-07-23 05:00:46: 2 stuck for 26s!