Re: [PATCH 5/8] pc-bios: s390x: Move panic() into header and add infinite loop

[Cornelia Huck]

On Tue, 24 Mar 2020 11:08:44 -0400
Janosch Frank <address@hidden> wrote:

> panic() was defined for the ccw and net bios, i.e. twice, so it's
> cleaner to rather put it into the header.

They were also slightly different, so unifying them makes sense.

> 
> Also let's add an infinite loop into the assembly of disabled_wait() so
> the caller doesn't need to take care of it.
> 
> Signed-off-by: Janosch Frank <address@hidden>
> Reviewed-by: Pierre Morel <address@hidden>
> ---
>  pc-bios/s390-ccw/main.c     | 7 -------
>  pc-bios/s390-ccw/netmain.c  | 8 --------
>  pc-bios/s390-ccw/s390-ccw.h | 7 ++++++-
>  pc-bios/s390-ccw/start.S    | 5 +++--
>  4 files changed, 9 insertions(+), 18 deletions(-)
> 

> @@ -91,6 +90,12 @@ bool menu_is_enabled_enum(void);
>  
>  #define MAX_BOOT_ENTRIES  31
>  
> +static inline void panic(const char *string)
> +{
> +    sclp_print(string);
> +    disabled_wait();
> +}
> +
>  static inline void fill_hex(char *out, unsigned char val)
>  {
>      const char hex[] = "0123456789abcdef";
> diff --git a/pc-bios/s390-ccw/start.S b/pc-bios/s390-ccw/start.S
> index aa8fceb19da2164a..35be141d8da38d07 100644
> --- a/pc-bios/s390-ccw/start.S
> +++ b/pc-bios/s390-ccw/start.S
> @@ -47,8 +47,9 @@ memsetxc:
>   */
>       .globl disabled_wait
>  disabled_wait:
> -        larl %r1,disabled_wait_psw
> -        lpswe   0(%r1)
> +        larl %r1,disabled_wait_psw
> +        lpswe        0(%r1)
> +1:   j       1b
>  
>  
>  /*

Possibly dumb question: Does checking code now figure out correctly
that code flow does not continue after disabled_wait()?