graphic: 0.909 operating system: 0.903 KVM: 0.881 system: 0.863 x86: 0.812 architecture: 0.788 hypervisor: 0.788 semantic: 0.775 files: 0.766 device: 0.764 performance: 0.758 mistranslation: 0.718 ppc: 0.710 vnc: 0.709 network: 0.697 kernel: 0.693 PID: 0.683 user-level: 0.681 socket: 0.636 debug: 0.604 arm: 0.601 boot: 0.569 permissions: 0.560 virtual: 0.540 risc-v: 0.488 register: 0.485 peripherals: 0.484 VMM: 0.474 i386: 0.462 TCG: 0.429 assembly: 0.395 alpha: 0.246 [Bug] "-ht" flag ignored under KVM - guest still reports HT Hi Community, We have observed that the 'ht' feature bit cannot be disabled when QEMU runs with KVM acceleration. qemu-system-x86_64 \ --enable-kvm \ -machine q35 \ -cpu host,-ht \ -smp 4 \ -m 4G \ -drive file=rootfs.img,format=raw \ -nographic \ -append 'console=ttyS0 root=/dev/sda rw' Because '-ht' is specified, the guest should expose no HT capability (cpuid.1.edx[28] = 0), and /proc/cpuinfo shouldn't show HT feature, but we still saw ht in linux guest when run 'cat /proc/cpuinfo'. XiaoYao mentioned that: It has been the behavior of QEMU since commit 400281af34e5ee6aa9f5496b53d8f82c6fef9319 Author: Andre Przywara Date: Wed Aug 19 15:42:42 2009 +0200 set CPUID bits to present cores and threads topology that we cannot remove HT CPUID bit from guest via "-cpu xxx,-ht" if the VM has >= 2 vcpus. I'd like to know whether there's a plan to address this issue, or if the current behaviour is considered acceptable. Best regards, Ewan.