2017-08-15 16:39+0800, Li Zhijian: > Hi guys > > i encountered a problem when i test vmx related cases > > the test log like below > [adam@skylake kvm-unit-tests]$ ./run_tests.sh > SKIP vmx_null (0 tests) > [adam@skylake kvm-unit-tests]$ cat logs/ > SUMMARY vmx_null.log > [adam@skylake kvm-unit-tests]$ cat logs/vmx_null.log > warning: host doesn't support requested feature: CPUID.01H:ECX.vmx [bit 5] > timeout -k 1s --foreground 90s /usr/bin/qemu-system-x86_64 -nodefaults -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio -device pci-testdev -machine accel=kvm -kernel x86/vmx.flat -smp 1 -cpu host,+vmx -append null # -initrd /tmp/tmp.wTXf483ild > enabling apic > paging enabled > cr0 = 80010011 > cr3 = 469000 > cr4 = 20 > WARNING: vmx not supported, add '-cpu host' > SUMMARY: 0 tests > > why the test output this warning, my skylake i5-6500 machine can support vmx feature, and how i can fix it. The warning means that KVM doesn't allow the guest to see the vmx feature. You are most likely without nested vmx, because it is disabled by default: % cat /sys/module/kvm_intel/parameters/nested N In order to turn it on, reload the "kvm_intel" module with "nested=Y" parameter. modprobe -r kvm_intel; modprobe kvm_intel nested=y If you want to have this automatically, add options kvm_intel nested=1 to /etc/modprobe.d/kvm.conf. > i tried the same test at my another haswell(i7-4790) machine(has the same kernel) doesn't occur this issue. Not sure why it works on the other machine -- is it a different distro? Thanks.
