Re: [Qemu-devel] [PATCH v2] ppc: spapr-rtas - implement os-term rtas call

[Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>]

Alexander Graf <agraf@suse.de> writes:

> On 12.06.14 14:09, Nikunj A Dadhania wrote:
>> PAPR compliant guest calls this in absence of kdump. After
>> receiving this call qemu could trigger a guest dump. This guest dump
>> can be used to analyse using crash tool.
>>
>> Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
>> ---
>>
>> v2: indentation fixes
>>
>>   hw/ppc/spapr_rtas.c | 32 ++++++++++++++++++++++++++++++++
>>   1 file changed, 32 insertions(+)
>>
>> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
>> index ea4a2b2..f030e73 100644
>> --- a/hw/ppc/spapr_rtas.c
>> +++ b/hw/ppc/spapr_rtas.c
>> @@ -29,6 +29,8 @@
>>   #include "sysemu/char.h"
>>   #include "hw/qdev.h"
>>   #include "sysemu/device_tree.h"
>> +#include "qapi/qmp/qjson.h"
>> +#include "monitor/monitor.h"
>>   
>>   #include "hw/ppc/spapr.h"
>>   #include "hw/ppc/spapr_vio.h"
>> @@ -267,6 +269,34 @@ static void rtas_ibm_set_system_parameter(PowerPCCPU *cpu,
>>       rtas_st(rets, 0, ret);
>>   }
>>   
>> +static void rtas_ibm_os_term(PowerPCCPU *cpu,
>> +                             sPAPREnvironment *spapr,
>> +                             uint32_t token, uint32_t nargs,
>> +                             target_ulong args,
>> +                             uint32_t nret, target_ulong rets)
>> +{
>> +    target_ulong ret = 0;
>> +    QObject *data;
>> +
>> +    data = qobject_from_jsonf("{ 'action': %s }", "pause");
>> +    monitor_protocol_event(QEVENT_GUEST_PANICKED, data);
>> +    qobject_decref(data);
>> +    vm_stop(RUN_STATE_GUEST_PANICKED);
>> +
>> +    rtas_st(rets, 0, ret);
>> +}
>> +
>> +static void rtas_ibm_ext_os_term(PowerPCCPU *cpu,
>> +                                 sPAPREnvironment *spapr,
>> +                                 uint32_t token, uint32_t nargs,
>> +                                 target_ulong args,
>> +                                 uint32_t nret, target_ulong rets)
>> +{
>> +    target_ulong ret = 0;
>> +
>> +    rtas_st(rets, 0, ret);
>> +}
>> +
>>   static struct rtas_call {
>>       const char *name;
>>       spapr_rtas_fn fn;
>> @@ -392,6 +422,8 @@ static void core_rtas_register_types(void)
>>                           rtas_ibm_get_system_parameter);
>>       spapr_rtas_register("ibm,set-system-parameter",
>>                           rtas_ibm_set_system_parameter);
>> +    spapr_rtas_register("ibm,os-term", rtas_ibm_os_term);
>> +    spapr_rtas_register("ibm,extended-os-term", rtas_ibm_ext_os_term);
>
> Why do we need the extended-os-term if we don't do anything with it?

Linux kernel checks for both of them because of legacy:

arch/powerpc/kernel/rtas.c:

void rtas_os_term(char *str)
{
[...]
        /*
         * Firmware with the ibm,extended-os-term property is guaranteed
         * to always return from an ibm,os-term call. Earlier versions without
         * this property may terminate the partition which we want to avoid
         * since it interferes with panic_timeout.
         */
        if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term") ||
            RTAS_UNKNOWN_SERVICE == rtas_token("ibm,extended-os-term"))
                return;

[...]
}

Regards,
Nikunj