id = 1677
title = "qemu-system-x86_64 cannot run on Windows when -smp is specified with a value higher than `1`. An important argument for any expectation of VM performance"
state = "opened"
created_at = "2023-06-01T23:26:59.176Z"
closed_at = "n/a"
labels = ["hostos: Windows"]
url = "https://gitlab.com/qemu-project/qemu/-/issues/1677"
host-os = "Windows 10"
host-arch = "x86_64 (Intel)"
qemu-version = "QEMU emulator version 8.0.0 (v8.0.0-12024-gd6b71850be-dirty)"
guest-os = "NA - Grub2 boot process fails for multiple ISO flavours"
guest-arch = "x86_64"
description = """qemu-system-x86_64 seems to crash on Windows the moment you try to use -smp to define more vcpus, even the basic usage of `-smp 4` will cause qemu to segfault after the guest's boot option is selected."""
reproduce = """1. `qemu-system-x86_64 -smp 4 -cdrom rhel-9.2-x86_64-dvd.iso -drive if=pflash,format=raw,unit=0,readonly=on,file=edk2-x64/OVMF_CODE.fd -m 6G -nodefaults -serial mon:stdio`
2. Select the boot option to begin your installation
3. qemu hangs for 10 or so seconds then throws a Segmentation Fault."""
additional = """1. This does not happen if -smp arguments are omitted, but running VMs with a single vcpu thread is slow and painful.
2. This still happens even without OVMF (Traditional bios booting)
3. This still happens even without -defaults and without a serial device

Only output from qemu at death is `Segmentation fault`"""