Re: [qemu-s390x] [PATCH] s390x/cpumodel: model PTFF subfunctions for Multiple-epoch facility

[David Hildenbrand]

On 05.02.2018 10:09, David Hildenbrand wrote:
> For now, the kernel does not properly indicate configured CPU subfunctions
> to the guest, but simply uses the host values (as support in KVM is still
> missing). That's why we missed to model the PTFF subfunctions that come
> with Multiple-epoch facility.
> 
> Let's properly add these, along with a new feature group.
> 
> Signed-off-by: David Hildenbrand <address@hidden>
> ---
>  target/s390x/cpu_features.c     |  5 +++++
>  target/s390x/cpu_features_def.h |  4 ++++
>  target/s390x/gen-features.c     | 10 ++++++++++
>  3 files changed, 19 insertions(+)
> 
> diff --git a/target/s390x/cpu_features.c b/target/s390x/cpu_features.c
> index 85d10b5710..8606e52ca0 100644
> --- a/target/s390x/cpu_features.c
> +++ b/target/s390x/cpu_features.c
> @@ -156,8 +156,12 @@ static const S390FeatDef s390_features[] = {
>      FEAT_INIT("ptff-qpc", S390_FEAT_TYPE_PTFF, 3, "PTFF Query Physical 
> Clock"),
>      FEAT_INIT("ptff-qui", S390_FEAT_TYPE_PTFF, 4, "PTFF Query UTC 
> Information"),
>      FEAT_INIT("ptff-qtou", S390_FEAT_TYPE_PTFF, 5, "PTFF Query TOD Offset 
> User"),
> +    FEAT_INIT("ptff-qsie", S390_FEAT_TYPE_PTFF, 10, "PTFF Query Steering 
> Information Extended"),
> +    FEAT_INIT("ptff-qtoue", S390_FEAT_TYPE_PTFF, 13, "PTFF Query TOD Offset 
> User Extended"),
>      FEAT_INIT("ptff-sto", S390_FEAT_TYPE_PTFF, 65, "PTFF Set TOD Offset"),
>      FEAT_INIT("ptff-stou", S390_FEAT_TYPE_PTFF, 69, "PTFF Set TOD Offset 
> User"),
> +    FEAT_INIT("ptff-stoe", S390_FEAT_TYPE_PTFF, 73, "PTFF Set TOD Offset 
> Extended"),
> +    FEAT_INIT("ptff-stoue", S390_FEAT_TYPE_PTFF, 77, "PTFF Set TOD Offset 
> User Extended"),
>  
>      FEAT_INIT("kmac-dea", S390_FEAT_TYPE_KMAC, 1, "KMAC DEA"),
>      FEAT_INIT("kmac-tdea-128", S390_FEAT_TYPE_KMAC, 2, "KMAC TDEA-128"),
> @@ -445,6 +449,7 @@ static S390FeatGroupDef s390_feature_groups[] = {
>      FEAT_GROUP_INIT("plo", PLO, "Perform-locked-operation facility"),
>      FEAT_GROUP_INIT("tods", TOD_CLOCK_STEERING, "Tod-clock-steering 
> facility"),
>      FEAT_GROUP_INIT("gen13ptff", GEN13_PTFF, "PTFF enhancements introduced 
> with z13"),
> +    FEAT_GROUP_INIT("mepochptff", MEPOCH_PTFF, "PTFF enhancements introduced 
> with Multiple-epoch facility"),
>      FEAT_GROUP_INIT("msa", MSA, "Message-security-assist facility"),
>      FEAT_GROUP_INIT("msa1", MSA_EXT_1, "Message-security-assist-extension 1 
> facility"),
>      FEAT_GROUP_INIT("msa2", MSA_EXT_2, "Message-security-assist-extension 2 
> facility"),
> diff --git a/target/s390x/cpu_features_def.h b/target/s390x/cpu_features_def.h
> index 4d930871b4..7c5915c7b2 100644
> --- a/target/s390x/cpu_features_def.h
> +++ b/target/s390x/cpu_features_def.h
> @@ -151,8 +151,12 @@ typedef enum {
>      S390_FEAT_PTFF_QPT,
>      S390_FEAT_PTFF_QUI,
>      S390_FEAT_PTFF_QTOU,
> +    S390_FEAT_PTFF_QSIE,
> +    S390_FEAT_PTFF_QTOUE,
>      S390_FEAT_PTFF_STO,
>      S390_FEAT_PTFF_STOU,
> +    S390_FEAT_PTFF_STOE,
> +    S390_FEAT_PTFF_STOUE,
>  
>      /* KMAC */
>      S390_FEAT_KMAC_DEA,
> diff --git a/target/s390x/gen-features.c b/target/s390x/gen-features.c
> index 58b6ac484e..8c04ff913f 100644
> --- a/target/s390x/gen-features.c
> +++ b/target/s390x/gen-features.c
> @@ -59,6 +59,12 @@
>      S390_FEAT_PTFF_QTOU, \
>      S390_FEAT_PTFF_STOU
>  
> +#define S390_FEAT_GROUP_MEPOCH_PTFF \
> +    S390_FEAT_PTFF_QSIE, \
> +    S390_FEAT_PTFF_QTOUE, \
> +    S390_FEAT_PTFF_STOE, \
> +    S390_FEAT_PTFF_STOUE
> +
>  #define S390_FEAT_GROUP_MSA \
>      S390_FEAT_MSA, \
>      S390_FEAT_KMAC_DEA, \
> @@ -219,6 +225,9 @@ static uint16_t group_TOD_CLOCK_STEERING[] = {
>  static uint16_t group_GEN13_PTFF[] = {
>      S390_FEAT_GROUP_GEN13_PTFF,
>  };
> +static uint16_t group_MEPOCH_PTFF[] = {
> +    S390_FEAT_GROUP_MEPOCH_PTFF,
> +};
>  static uint16_t group_MSA[] = {
>      S390_FEAT_GROUP_MSA,
>  };
> @@ -665,6 +674,7 @@ static FeatGroupDefSpec FeatGroupDef[] = {
>      FEAT_GROUP_INITIALIZER(PLO),
>      FEAT_GROUP_INITIALIZER(TOD_CLOCK_STEERING),
>      FEAT_GROUP_INITIALIZER(GEN13_PTFF),
> +    FEAT_GROUP_INITIALIZER(MEPOCH_PTFF),
>      FEAT_GROUP_INITIALIZER(MSA),
>      FEAT_GROUP_INITIALIZER(MSA_EXT_1),
>      FEAT_GROUP_INITIALIZER(MSA_EXT_2),
> 

Guess this hunk is missing:

diff --git a/target/s390x/gen-features.c b/target/s390x/gen-features.c
index 8c04ff913f..cfb371dac3 100644
--- a/target/s390x/gen-features.c
+++ b/target/s390x/gen-features.c
@@ -475,6 +475,7 @@ static uint16_t full_GEN14_GA1[] = {
     S390_FEAT_CMM_NT,
     S390_FEAT_HPMA2,
     S390_FEAT_SIE_KSS,
+    S390_FEAT_GROUP_MEPOCH_PTFF,
 };
 
 /* Default features (in order of release)


And we should most probably add this:

diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c
index bfd14723f1..deb870921b 100644
--- a/target/s390x/kvm.c
+++ b/target/s390x/kvm.c
@@ -2221,6 +2221,14 @@ void kvm_s390_get_host_cpu_model(S390CPUModel *model, 
Error **errp)
         return;
     }
 
+    /* PTFF subfunctions might be indicated although kernel support missing */
+    if (!test_bit(S390_FEAT_MULTIPLE_EPOCH, model->features)) {
+        clear_bit(S390_FEAT_PTFF_QSIE, model->features);
+        clear_bit(S390_FEAT_PTFF_QTOUE, model->features);
+        clear_bit(S390_FEAT_PTFF_STOE, model->features);
+        clear_bit(S390_FEAT_PTFF_STOUE, model->features);
+    }
+
     /* with cpu model support, CMM is only indicated if really available */
     if (kvm_s390_cmma_available()) {
         set_bit(S390_FEAT_CMM, model->features);


Unfortunately I don't have access to a z14.

-- 

Thanks,

David / dhildenb