Re: [Qemu-devel] [Qemu-ppc] [PATCH 4/4] spapr: Add RTAS sysparm SPLPAR Characteristics

[Alexander Graf <agraf@suse.de>]

On 24.06.14 02:22, Sam Bobroff wrote:
> Add support for the SPLPAR Characteristics parameter to the emulated
> RTAS call ibm,get-system-parameter.
>
> The support provides just enough information to allow "cat
> /proc/powerpc/lparcfg" to succeed without generating a kernel error
> message.
>
> Without this patch the above command will produce the following kernel
> message: arch/powerpc/platforms/pseries/lparcfg.c \
> parse_system_parameter_string Error calling get-system-parameter \
> (0xfffffffd)
>
> Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
> ---
>   hw/ppc/spapr_rtas.c | 13 +++++++++++++
>   1 file changed, 13 insertions(+)
>
> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
> index 8d94845..4270e7a 100644
> --- a/hw/ppc/spapr_rtas.c
> +++ b/hw/ppc/spapr_rtas.c
> @@ -224,6 +224,7 @@ static void rtas_stop_self(PowerPCCPU *cpu, sPAPREnvironment *spapr,
>       env->msr = 0;
>   }
>   
> +#define SPLPAR_CHARACTERISTICS      20
>   #define DIAGNOSTICS_RUN_MODE        42
>   #define UUID                        48
>   
> @@ -238,8 +239,20 @@ static void rtas_ibm_get_system_parameter(PowerPCCPU *cpu,
>       target_ulong length = rtas_ld(args, 2);
>       target_ulong ret = RTAS_OUT_SUCCESS;
>       uint8_t zero = 0;
> +    uint8_t param_buf[64];
> +    int param_len;
>   
>       switch (parameter) {
> +    case SPLPAR_CHARACTERISTICS:
> +        param_len = snprintf((char *)param_buf, sizeof param_buf,
> +                             "MaxEntCap=%d,MaxPlatProcs=%d",
> +                             max_cpus, smp_cpus);

We have a nice g_strdup_printf() helper function that allocates memory 
for us automatically based on the printf size. Just use that one here ;).


Alex