Re: [PATCH v18 2/7] ppc: spapr: Introduce FWNMI capability

[Ganesh <ganeshgr@linux.ibm.com>]

On 1/6/20 2:37 PM, Greg Kurz wrote:
> On Thu,  2 Jan 2020 13:21:06 +0530
> Ganesh Goudar <ganeshgr@linux.ibm.com> wrote:
>
>> From: Aravinda Prasad <arawinda.p@gmail.com>
>>
>> Introduce fwnmi an spapr capability and validate it against
>> the kernels existing capability by trying to enable it.
> I see this patch indeed adds a KVM helper to do that but it isn't
> called before some later patch in this series. Please update the
> changelog to make it clear this is just a preparatory patch that
> doesn't change any existing behavior.
Ok, ill update the commit message
>
>> [eliminate cap_ppc_fwnmi, add fwnmi cap to migration state
>>   and reprhase the commit message]
>> Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
> Personal changes and S-o-b are usually appended to the existing
> ones...
>
>> Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
> ... i.e. here.
ok
>
>> ---
>>   hw/ppc/spapr.c         |  2 ++
>>   hw/ppc/spapr_caps.c    | 18 ++++++++++++++++++
>>   include/hw/ppc/spapr.h |  5 ++++-
>>   target/ppc/kvm.c       |  8 ++++++++
>>   target/ppc/kvm_ppc.h   |  6 ++++++
>>   5 files changed, 38 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
>> index f11422fc41..c91e64aad0 100644
>> --- a/hw/ppc/spapr.c
>> +++ b/hw/ppc/spapr.c
>> @@ -1994,6 +1994,7 @@ static const VMStateDescription vmstate_spapr = {
>>           &vmstate_spapr_dtb,
>>           &vmstate_spapr_cap_large_decr,
>>           &vmstate_spapr_cap_ccf_assist,
>> +        &vmstate_spapr_cap_fwnmi,
>>           NULL
>>       }
>>   };
>> @@ -4400,6 +4401,7 @@ static void spapr_machine_class_init(ObjectClass *oc, void *data)
>>       smc->default_caps.caps[SPAPR_CAP_NESTED_KVM_HV] = SPAPR_CAP_OFF;
>>       smc->default_caps.caps[SPAPR_CAP_LARGE_DECREMENTER] = SPAPR_CAP_ON;
>>       smc->default_caps.caps[SPAPR_CAP_CCF_ASSIST] = SPAPR_CAP_OFF;
>> +    smc->default_caps.caps[SPAPR_CAP_FWNMI_MCE] = SPAPR_CAP_OFF;
>>       spapr_caps_add_properties(smc, &error_abort);
>>       smc->irq = &spapr_irq_dual;
>>       smc->dr_phb_enabled = true;
>> diff --git a/hw/ppc/spapr_caps.c b/hw/ppc/spapr_caps.c
>> index 481dfd2a27..3001098601 100644
>> --- a/hw/ppc/spapr_caps.c
>> +++ b/hw/ppc/spapr_caps.c
>> @@ -496,6 +496,14 @@ static void cap_ccf_assist_apply(SpaprMachineState *spapr, uint8_t val,
>>       }
>>   }
>>   
>> +static void cap_fwnmi_mce_apply(SpaprMachineState *spapr, uint8_t val,
>> +                                Error **errp)
>> +{
>> +    if (!val) {
>> +        return; /* Disabled by default */
>> +    }
>> +}
>> +
>>   SpaprCapabilityInfo capability_table[SPAPR_CAP_NUM] = {
>>       [SPAPR_CAP_HTM] = {
>>           .name = "htm",
>> @@ -595,6 +603,15 @@ SpaprCapabilityInfo capability_table[SPAPR_CAP_NUM] = {
>>           .type = "bool",
>>           .apply = cap_ccf_assist_apply,
>>       },
>> +    [SPAPR_CAP_FWNMI_MCE] = {
>> +        .name = "fwnmi-mce",
>> +        .description = "Handle fwnmi machine check exceptions",
>> +        .index = SPAPR_CAP_FWNMI_MCE,
>> +        .get = spapr_cap_get_bool,
>> +        .set = spapr_cap_set_bool,
>> +        .type = "bool",
>> +        .apply = cap_fwnmi_mce_apply,
>> +    },
>>   };
>>   
>>   static SpaprCapabilities default_caps_with_cpu(SpaprMachineState *spapr,
>> @@ -734,6 +751,7 @@ SPAPR_CAP_MIG_STATE(hpt_maxpagesize, SPAPR_CAP_HPT_MAXPAGESIZE);
>>   SPAPR_CAP_MIG_STATE(nested_kvm_hv, SPAPR_CAP_NESTED_KVM_HV);
>>   SPAPR_CAP_MIG_STATE(large_decr, SPAPR_CAP_LARGE_DECREMENTER);
>>   SPAPR_CAP_MIG_STATE(ccf_assist, SPAPR_CAP_CCF_ASSIST);
>> +SPAPR_CAP_MIG_STATE(fwnmi, SPAPR_CAP_FWNMI_MCE);
>>   
>>   void spapr_caps_init(SpaprMachineState *spapr)
>>   {
>> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
>> index 61f005c6f6..7bc5fc3a9e 100644
>> --- a/include/hw/ppc/spapr.h
>> +++ b/include/hw/ppc/spapr.h
>> @@ -79,8 +79,10 @@ typedef enum {
>>   #define SPAPR_CAP_LARGE_DECREMENTER     0x08
>>   /* Count Cache Flush Assist HW Instruction */
>>   #define SPAPR_CAP_CCF_ASSIST            0x09
>> +/* FWNMI machine check handling */
>> +#define SPAPR_CAP_FWNMI_MCE             0x0A
>>   /* Num Caps */
>> -#define SPAPR_CAP_NUM                   (SPAPR_CAP_CCF_ASSIST + 1)
>> +#define SPAPR_CAP_NUM                   (SPAPR_CAP_FWNMI_MCE + 1)
>>   
>>   /*
>>    * Capability Values
>> @@ -869,6 +871,7 @@ extern const VMStateDescription vmstate_spapr_cap_hpt_maxpagesize;
>>   extern const VMStateDescription vmstate_spapr_cap_nested_kvm_hv;
>>   extern const VMStateDescription vmstate_spapr_cap_large_decr;
>>   extern const VMStateDescription vmstate_spapr_cap_ccf_assist;
>> +extern const VMStateDescription vmstate_spapr_cap_fwnmi;
>>   
>>   static inline uint8_t spapr_get_cap(SpaprMachineState *spapr, int cap)
>>   {
>> diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
>> index d1c334f0e3..518de7e4b7 100644
>> --- a/target/ppc/kvm.c
>> +++ b/target/ppc/kvm.c
>> @@ -2060,6 +2060,14 @@ void kvmppc_set_mpic_proxy(PowerPCCPU *cpu, int mpic_proxy)
>>       }
>>   }
>>   
>> +int kvmppc_set_fwnmi(void)
>> +{
>> +    PowerPCCPU *cpu = POWERPC_CPU(first_cpu);
>> +    CPUState *cs = CPU(cpu);
>> +
>> +    return kvm_vcpu_enable_cap(cs, KVM_CAP_PPC_FWNMI, 0);
>> +}
>> +
>>   int kvmppc_smt_threads(void)
>>   {
>>       return cap_ppc_smt ? cap_ppc_smt : 1;
>> diff --git a/target/ppc/kvm_ppc.h b/target/ppc/kvm_ppc.h
>> index f22daabf51..eedb15d48e 100644
>> --- a/target/ppc/kvm_ppc.h
>> +++ b/target/ppc/kvm_ppc.h
>> @@ -27,6 +27,7 @@ void kvmppc_enable_h_page_init(void);
>>   void kvmppc_set_papr(PowerPCCPU *cpu);
>>   int kvmppc_set_compat(PowerPCCPU *cpu, uint32_t compat_pvr);
>>   void kvmppc_set_mpic_proxy(PowerPCCPU *cpu, int mpic_proxy);
>> +int kvmppc_set_fwnmi(void);
>>   int kvmppc_smt_threads(void);
>>   void kvmppc_error_append_smt_possible_hint(Error *const *errp);
>>   int kvmppc_set_smt_threads(int smt);
>> @@ -159,6 +160,11 @@ static inline void kvmppc_set_mpic_proxy(PowerPCCPU *cpu, int mpic_proxy)
>>   {
>>   }
>>   
>> +static inline int kvmppc_set_fwnmi(void)
>> +{
>> +    return -1;
>> +}
>> +
>>   static inline int kvmppc_smt_threads(void)
>>   {
>>       return 1;