I have a very simple use case for QEMU that doesn't seem to be possible, despite suggestions in some parts of the documentation that it should be, or am I doing something wrong?
The basic issue is how to get QEMU to provide new processor functionality for the host on the same architecture. In other words, add CPU flags in the accelerator that are not supported by the host CPU via emulation.
For example, I want to run an application that contains SSE4.1 instructions on a host machine that doesn't have support for these. If I try to do it with QEMUt, I'm just given warnings at startup and it doesn't seem that they have been made available?
$ qemu-system-x86_64 -enable-kvm -cpu "host,+ssse3,+sse4.1" -m 256M -smp 1 -boot d -cdrom /home/chris/vmware/iso/TinyCorePure64-15.0.iso -vga qxl -device AC97
qemu-system-x86_64: warning: host doesn't support requested feature: CPUID.01H:ECX.ssse3 [bit 9]
qemu-system-x86_64: warning: host doesn't support requested feature: CPUID.01H:ECX.sse4.1 [bit 19]
Is there something I can change in that command line to make this work, or why is this impossible? I know emulation is going to be inefficient and slow, but my main concern is getting it to actually work at all!