Re: [PATCH v4 12/12] .travis.yml: Add a KVM-only Aarch64 job

Thomas Huth
2020-10-03T10:14:32Z

On 03/10/2020 12.03, Richard Henderson wrote:
> On 9/29/20 5:43 PM, Philippe Mathieu-Daudé wrote:
>> Add a job to build QEMU on Aarch64 with TCG disabled, so
>> this configuration won't bitrot over time.
>>
>> We explicitly modify default-configs/aarch64-softmmu.mak to
>> only select the 'virt' and 'SBSA-REF' machines.
>
> I really wish we didn't have to do this.
>
> Can't we e.g. *not* list all of the arm boards explicitly in default-configs,
> but use the Kconfig "default y if ..."?
>
> Seems like that would let --disable-tcg work as expected.
> One should still be able to create custom configs with e.g.
> CONFIG_EXYNOS4=n or CONIFIG_ARM_V4=n, correct?

But that would be different from how we handle all other targets currently...
IMHO we shoud go into a different direction instead, e.g. by adding a
"--kconfig-dir" switch to the configure script. If it has not been
specified, the configs will be read from default-configs/ (or maybe we
should then rename it to configs/default/). But if the switch has been
specified with a directory as parameter, the config files will be read from
that directory instead. We could then have folders like:

- configs/default (current default-configs)
- configs/no-tcg (all machines that work without tcg)
- configs/lean-kvm (for "nemu"-style minimalistic settings)

etc.

What do you think?

Thomas