Re: [Qemu-trivial] [Qemu-devel] [RFC PATCH 4/4] qemu-options: Do not show -enable-kvm and -enable-hax in the docs anymore

[Markus Armbruster]

Paolo Bonzini <address@hidden> writes:

> On 22/06/2018 21:35, Eduardo Habkost wrote:
>>>> Why is this better than using KVM by default if it's available?
>>> The answer is (as almost always): Compatibility with migration. Nobody
>>> dares to sacrifice that chicken :-(
>> We can now kill it if we announce the feature as deprecated a
>> couple of releases in advance.
>> 
>> If we declare that compatibility when the accelerator is omitted
>> is deprecated in 3.0, in QEMU 3.3 we will be free to choose a
>> different default accelerator.
>
> We can, we don't necessarily want it.
>
> The status quo is that people using KVM are invoking qemu as qemu-kvm,
> people using TCG are invoking qemu as qemu-system-*.  All distros are
> shipping a qemu-kvm or more rarely kvm binary, which is invariably a
> wrapper script except for RHEL because RHEL doesn't have a qemu-system-*
> binary at all.
>
> By the way, changing qemu-system-*'s default to e.g. RHEL's "kvm or tcg"
> would not help distros that have "-accel kvm" in their /usr/bin/qemu-kvm
> script.

It wouldn't hurt them, either.

Attentive distros could even replace the wrapper script by a link.

> All in all, it seems simpler for me to take the status quo, which is
> what non-RHEL distros do, and make it part of upstream.
>
> Paolo