Re: [PATCH] xen/argo: Command line handling improvements

["Daniel P. Smith" <dpsmith@xxxxxxxxxxxxxxxxxxxx>]

On 5/20/25 10:10, Andrew Cooper wrote:
> Treat "argo" on the command line as a positive boolean, rather than requiring
> the user to pass "argo=1/on/enable/true".
>
> Move both opt_argo* variables into __ro_after_init.  They're set during
> command line parsing and never modified thereafter.
>
> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> ---
> CC: Christopher Clark <christopher.w.clark@xxxxxxxxx>
> CC: Daniel P. Smith <dpsmith@xxxxxxxxxxxxxxxxxxxx>
> CC: Denis Mukhin <dmkhn@xxxxxxxxx>
>
> Found while
> ---
>   xen/common/argo.c | 9 ++++++---
>   1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/xen/common/argo.c b/xen/common/argo.c
> index cbe8911a4364..027b37b18a6c 100644
> --- a/xen/common/argo.c
> +++ b/xen/common/argo.c
> @@ -79,8 +79,8 @@ DEFINE_XEN_GUEST_HANDLE(xen_argo_unregister_ring_t);
>   DEFINE_COMPAT_HANDLE(compat_argo_iov_t);
>   #endif
>   
> -static bool __read_mostly opt_argo;
> -static bool __read_mostly opt_argo_mac_permissive;
> +static bool __ro_after_init opt_argo;
> +static bool __ro_after_init opt_argo_mac_permissive;
>   
>   static int __init cf_check parse_argo(const char *s)
>   {
> @@ -92,7 +92,10 @@ static int __init cf_check parse_argo(const char *s)
>           if ( !ss )
>               ss = strchr(s, '\0');
>   
> -        if ( (val = parse_bool(s, ss)) >= 0 )
> +        /* Intepret "argo" as a positive boolean. */
> +        if ( *s == '\0' )
> +            opt_argo = true;
> +        else if ( (val = parse_bool(s, ss)) >= 0 )
>               opt_argo = val;
>           else if ( (val = parse_boolean("mac-permissive", s, ss)) >= 0 )
>               opt_argo_mac_permissive = val;
>
> base-commit: 293abb9e0c5e8df96cc5dfe457c62dfcb7542b19
While it is logical, this does technically change the behavior of the 
command line flag. Should there be an update to xen-command-line.pandoc 
to clarify that the list is optional?
Other than the doc concern,

Reviewed-by: Daniel P. Smith <dpsmith@xxxxxxxxxxxxxxxxxxxx>