Re: [kvm-unit-tests PATCH] riscv: lib: Add sbi-exit-code to configure and environment

[Andrew Jones <andrew.jones@linux.dev>]

On Thu, Jul 03, 2025 at 06:36:00AM -0700, Jesse Taube wrote:
> Add --[enable|disable]-sbi-exit-code to configure script.
> With the default value disabled.
> Add a check for SBI_PASS_EXIT_CODE in the environment, so that passing
> of the test status is configurable from both the
> environment and the configure script
> 
> Signed-off-by: Jesse Taube <jesse@rivosinc.com>
> ---
>  configure      | 11 +++++++++++
>  lib/riscv/io.c | 12 +++++++++++-
>  2 files changed, 22 insertions(+), 1 deletion(-)
> 
> diff --git a/configure b/configure
> index 20bf5042..7c949bdc 100755
> --- a/configure
> +++ b/configure
> @@ -67,6 +67,7 @@ earlycon=
>  console=
>  efi=
>  efi_direct=
> +sbi_exit_code=0
>  target_cpu=
>  
>  # Enable -Werror by default for git repositories only (i.e. developer builds)
> @@ -141,6 +142,9 @@ usage() {
>  	                           system and run from the UEFI shell. Ignored when efi isn't enabled
>  	                           and defaults to enabled when efi is enabled for riscv64.
>  	                           (arm64 and riscv64 only)
> +	    --[enable|disable]-sbi-exit-code
> +	                           Enable or disable sending pass/fail exit code to SBI SRST.
> +	                           (disabled by default, riscv only)
>  EOF
>      exit 1
>  }
> @@ -236,6 +240,12 @@ while [[ $optno -le $argc ]]; do
>  	--disable-efi-direct)
>  	    efi_direct=n
>  	    ;;
> +	--enable-sbi-exit-code)
> +	    sbi_exit_code=1
> +	    ;;
> +	--disable-sbi-exit-code)
> +	    sbi_exit_code=0
> +	    ;;
>  	--enable-werror)
>  	    werror=-Werror
>  	    ;;
> @@ -551,6 +561,7 @@ EOF
>  elif [ "$arch" = "riscv32" ] || [ "$arch" = "riscv64" ]; then
>      echo "#define CONFIG_UART_EARLY_BASE ${uart_early_addr}" >> lib/config.h
>      [ "$console" = "sbi" ] && echo "#define CONFIG_SBI_CONSOLE" >> lib/config.h
> +    echo "#define CONFIG_SBI_EXIT_CODE ${sbi_exit_code}" >> lib/config.h
>      echo >> lib/config.h
>  fi
>  echo "#endif" >> lib/config.h
> diff --git a/lib/riscv/io.c b/lib/riscv/io.c
> index b1163404..0e666009 100644
> --- a/lib/riscv/io.c
> +++ b/lib/riscv/io.c
> @@ -162,8 +162,18 @@ void halt(int code);
>  
>  void exit(int code)
>  {
> +	char *s = getenv("SBI_PASS_EXIT_CODE");
> +	bool pass_exit = CONFIG_SBI_EXIT_CODE;

This is the first case of what may become more common - a config variable
which also has an env override. I think it may be good convention to
name them the same, i.e. the env name would also be CONFIG_SBI_EXIT_CODE,
unless you think that would be confusing for some reason?

> +
>  	printf("\nEXIT: STATUS=%d\n", ((code) << 1) | 1);
> -	sbi_shutdown(code == 0);
> +
> +	if (s)
> +		pass_exit = (*s == '1' || *s == 'y' || *s == 'Y');

We now have this logic in four places[1]. I think it's time we factor it,
and it's counterpart "!(s && (*s == '0' || *s == 'n' || *s == 'N'))"
into a couple helper macros. I'm not sure where the best place for
those macros to live is, though. I guess libcflat.h, but we really
ought to split that thing apart someday...

[1]
 - twice in lib/errata.h
 - once in riscv/sbi-tests.ha
 - and now here

> +
> +	if (pass_exit)
> +		sbi_shutdown(code == 0);
> +	else
> +		sbi_shutdown(true);

nit: can be written more concisely as

 sbi_shutdown(pass_exit ? code == 0 : true)

>  	halt(code);
>  	__builtin_unreachable();
>  }
> -- 
> 2.43.0
>

Thanks,
drew