On 2018-10-09 15:14, Markus Armbruster wrote: > Markus Armbruster <arm...@redhat.com> writes: > >> Peter Maydell <peter.mayd...@linaro.org> writes: >> >>> On 5 October 2018 at 15:13, Thomas Huth <th...@redhat.com> wrote: >>>> When compiling with "--disable-tcg", we currently still use "tcg" >>>> as default accelerator. "kvm" should be used in this case instead. >>> >>> This part is non-controversial and makes good sense. >> >> Agreed. >> >>>> Also, some downstream distros provide QEMU binaries which have "kvm" >>>> in their names (e.g. "qemu-kvm" on RHEL or "kvm" on Ubuntu) that use >>>> KVM by default - and some users might want to do something similar >>>> with upstream binaries, too. Accomodate them by using "kvm:tcg" as >>>> default when we detect such a binary name. >>> >>> This part is much riskier and less clearly a good plan -- >>> do we really want our behaviour to vary based on the name >>> of the executable? Distros who want that sort of qemu-kvm >>> wrapper generally are providing it already (the Ubuntu one >>> is a 2-line shell script). >> >> I hate it when argv[0] affects behavior[*]. I hate shell wrappers less. >> >> If a system provides just one qemu executable, and its default >> accelerator should be something other than tcg:kvm, then there's a use > > Correction: "other than tcg". See configure_accelerator(). > > Remind me, why is "tcg" a good default?
"It's been always like this and we're keen on backward compatibility" ? Thomas
