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Date:   Thu, 18 May 2023 09:32:55 +0200
From:   Andrew Jones <ajones@ventanamicro.com>
To:     Haibo Xu <xiaobo55x@gmail.com>
Cc:     Haibo Xu <haibo1.xu@intel.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Anup Patel <anup@brainfault.org>,
        Atish Patra <atishp@atishpatra.org>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Shuah Khan <shuah@kernel.org>, kvm@vger.kernel.org,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org,
        linux-kselftest@vger.kernel.org, kvmarm@lists.linux.dev,
        Marc Zyngier <maz@kernel.org>,
        Oliver Upton <oliver.upton@linux.dev>,
        Sean Christopherson <seanjc@google.com>
Subject: Re: [PATCH 2/2] KVM: selftests: Add riscv get-reg-list test
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On Thu, May 18, 2023 at 12:17:18PM +0800, Haibo Xu wrote:
...
> > The idea of these *to_str functions is to dump output that can be
> > copy+pasted into a reg array (hence the trailing commas in print_reg
> > lines). So we can't just print random lines here or return '##UNKOWN##',
> > as that won't compile. Instead, the default should return
> >
> >   str_with_index("KVM_REG_RISCV_CONFIG_REG(##)", reg_off)
> >
> 
> Thanks for sharing the detailed idea, will fix it in next version!

I guess we could also return a string like,

"KVM_REG_RISCV_CONFIG_REG(##) /* UNKNOWN */"

as that would still compile and also convey the message that this
register doesn't have a name because the test doesn't know it yet.

...
> > We should share all the code above, except print_reg(), with aarch64.
> > I'll send a patch series that splits the arch-neutral code out of
> > the aarch64 test that you can base this test on.
> >
> 
> Good idea! I will rebase the patch based on your work.
>

Ok, I've pushed patches to [1]. This series introduces two things to KVM
selftests. Primarily it splits the aarch64/get-reg-list test into a
cross-arch get-reg-list test and an $ARCH_DIR/get-reg-list.o object file,
which the cross-arch test depends on. To do that, it also introduces the
concept of a "split test", a test that has a cross-arch part which depends
on an arch-specific part. Using a split test is cleaner than the
#ifdeffery we usually do for cross-arch tests.

I've added kvmarm@lists.linux.dev, Marc, Oliver, and Sean to the CC of
this message. You'll want to add them when you post v2 as well.

[1] https://github.com/jones-drew/linux/commits/arm64/kself/get-reg-list

Thanks,
drew