x86: 0.995 network: 0.940 architecture: 0.884 device: 0.849 performance: 0.842 mistranslation: 0.786 graphic: 0.732 ppc: 0.689 vnc: 0.612 semantic: 0.571 files: 0.539 permissions: 0.514 kernel: 0.511 socket: 0.504 boot: 0.469 TCG: 0.460 PID: 0.457 arm: 0.455 register: 0.451 user-level: 0.395 debug: 0.379 VMM: 0.357 peripherals: 0.341 hypervisor: 0.322 virtual: 0.316 risc-v: 0.284 KVM: 0.139 assembly: 0.043 i386: 0.009 qemu-system-x86_64 -net nic,model=help outputs to stderr instead of std qemu-system-x86_64 -net nic,model=help output comes to stderr instead of std qemu-system-x86_64 -net nic,model=help -> stdout qemu-system-x86_64 -machine help -> stdout qemu-system-x86_64 -cpu help -> stdout as of https://github.com/qemu/qemu/blob/044d65525f6ac2093042ae18dbf8c1300b5c1c18/net/net.c#L831 I run qemu 2.5 on x86_64 kind regards Finally fixed here: https://git.qemu.org/?p=qemu.git;a=commitdiff;h=7b71e03af98fd7b5e1