Re: [PATCH 8/9] hw/arm/virt: Restrict 32-bit CPUs to TCG

[Peter Maydell <peter.maydell@linaro.org>]

On Fri, 5 Feb 2021 at 14:44, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>
> Support for ARMv7 has been dropped in commit 82bf7ae84ce
> ("target/arm: Remove KVM support for 32-bit Arm hosts").
> Restrict the 32-bit CPUs to --enable-tcg builds.
>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  hw/arm/virt.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index f5e4a6ec914..ab6300650f9 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -197,8 +197,10 @@ static const int a15irqmap[] = {
>  };
>
>  static const char *valid_cpus[] = {
> +#ifdef CONFIG_TCG
>      ARM_CPU_TYPE_NAME("cortex-a7"),
>      ARM_CPU_TYPE_NAME("cortex-a15"),
> +#endif /* CONFIG_TCG */
>  #ifdef TARGET_AARCH64
>      ARM_CPU_TYPE_NAME("cortex-a53"),
>      ARM_CPU_TYPE_NAME("cortex-a57"),

How painful would it be to just have it check whether the
CPU type is present in the executable, rather than hard-coding an ifdef ?

I think that if you try to run the virt board with command line
arguments that (implicitly or explicitly) mean you've asked for
a CPU which isn't present in the QEMU executable, it should give
an error rather than silently selecting something else.

thanks
-- PMM