Re: [PATCH for-4.14] xen/hypfs: fix loglvl parameter setting

[Julien Grall <julien@xxxxxxx>]

Hi Juergen,

On 09/06/2020 16:45, Juergen Gross wrote:
> Writing the runtime parameters loglvl or guest_loglvl omits setting the
> new length of the resulting parameter value.
>
> Reported-by: George Dunlap <george.dunlap@xxxxxxxxxx>
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Reviewed-by: Julien Grall <jgrall@xxxxxxxxxx>

Although one unrelated comment below.

> ---
>   xen/drivers/char/console.c | 19 +++++++++++++++----
>   1 file changed, 15 insertions(+), 4 deletions(-)
>
> diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c
> index 56e24821b2..861ad53a8f 100644
> --- a/xen/drivers/char/console.c
> +++ b/xen/drivers/char/console.c
> @@ -241,14 +241,25 @@ static int _parse_loglvl(const char *s, int *lower, int 
> *upper, char *val)
>   
>   static int parse_loglvl(const char *s)
>   {
> -    return _parse_loglvl(s, &xenlog_lower_thresh, &xenlog_upper_thresh,
> -                         xenlog_val);
> +    int ret;
> +
> +    ret = _parse_loglvl(s, &xenlog_lower_thresh, &xenlog_upper_thresh,
> +                        xenlog_val);
> +    custom_runtime_set_var(param_2_parfs(parse_loglvl), xenlog_val);
Mixing function and variable name is pretty confusing. It took me 
sometimes to go through the macro maze to figure out what's happening.
It might be worth thinking to document more the custom_runtime_* interface.

Cheers,

--
Julien Grall