tugouxp <13824125...@163.com> writes:
> thank you. > > i just want to confirm one thing, that is whether the qemu can emulate a > whole operation system just by analysis instructions by instructions manually > without the support of KVM. > so from the answer you give to me, it is feasible, right? Yes - if you run qemu-system-$(ARCH) you are emulating a full machine with hardware attached. It can either use TCG or a HW based acceleration like KVM. HW based acceleration is only available on the same machine type. There is a third type - qemu-$(ARCH) which is often called linux-user mode. Here the translation engine only translates instruction from guest to the host and then maps system calls to the host system. This is isn't emulating a whole system but allows you to run binaries from one architecture on another. > > > > thanks very much! > > > > > > > > > > At 2018-12-21 17:01:02, "Alex Bennée" <alex.ben...@linaro.org> wrote: >> >>tugouxp <13824125...@163.com> writes: >> >>> Hi alex: >>> now my host machine did not have the "/dev/kvm" nodes and no chance to >>> make it exists. >>> so i want to know whether the "/dev/kvm" is mandatory for qemu to emulate >>> the whole system. >>> so i can make the emulation without the support of kvm mechanism. >> >>QEMU runs in two modes - full system emulation with TCG doesn't require >>KVM although it is relatively slow. On systems where there guest >>architecture is the same as the host architecture you can run with KMV >>(or HAX/WHPX/HVF) accelerators at near native speeds. >> >>The reasons for not having a /dev/kvm can vary but you haven't said what >>your host architecture is and what OS you are running so it's hard to >>offer advice here. >> >>-- >>Alex Bennée -- Alex Bennée