Re: [PATCH for-10.1] hw/riscv: do not mark any machine as default

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 27/3/25 14:02, Daniel Henrique Barboza wrote:
> Commit 5b4beba124 ("RISC-V Spike Machines") added the Spike machine and
> made it default for qemu-system-riscv32/64. It was the first RISC-V
> machine added in QEMU so setting it as default was sensible.
> 
> Today we have 7 risc64 and 6 riscv32 machines and having 'spike' as
> default machine is not intuitive. For example, [1] is a bug that was
> opened with the 'virt' board in mind, but given that the user didn't
> pass a '-machine' option, the user was using 'spike' without knowing.
> 
> The QEMU archs that defines a default machine usually defines it as the
> most used machine, e.g. PowerPC uses 'pseries' as default. So in theory
> we could change the default to the 'virt' machine, but that would make
> existing command lines that don't specify a machine option to act
> weird: they would silently use 'virt' instead of 'spike'.
> 
> Being explicit in the command line is desirable when we have a handful
> of boards available, so remove the default machine setting from RISC-V
> and make it obligatory to specify the board.
> 
> After this patch we'll throw an error if no machine is specified:
> 
> $ ./build/qemu-system-riscv64 --nographic qemu-system-riscv64: No
> machine specified, and there is no default Use -machine help to list
> supported machines
> 
> 'spike' users that aren't specifying their machines in the command line
> will be impacted and will need to add '-M spike' in their scripts.
> 
> [1] https://gitlab.com/qemu-project/qemu/-/issues/2467
> 
> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> ---
>   hw/riscv/spike.c | 1 -
>   1 file changed, 1 deletion(-)

I'm in favor of this change, which I believe is the correct way to
go, so:
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
but I'd rather we follow the deprecation process. Up to the maintainer.