[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [qemu-s390x] [PATCH] s390/cpumodel: default enable bpb and ppa15 for
From: |
David Hildenbrand |
Subject: |
Re: [qemu-s390x] [PATCH] s390/cpumodel: default enable bpb and ppa15 for z196 and later |
Date: |
Tue, 26 Jun 2018 14:49:23 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 |
s/s390/s390x
I can't think of a scenario where this would be harmful. Migration with
compat machines will still work correctly. -cpu qemu is not affected, so
TCG will also continue to work just fine.
Reviewed-by: David Hildenbrand <address@hidden>
On 26.06.2018 14:38, Christian Borntraeger wrote:
> Most systems and host kernels provide the necessary building blocks for
> bpb and ppa15. We can reverse the logic and default enable those
> features, while still allowing to disable it via cpu model.
>
> So let us add bpb and ppa15 to z196 and later default CPU model for the
> qemu 3.0 machine. (like -cpu z13). Older machine types (e.g.
> s390-ccw-virtio-2.12) will retain the old value and not provide those
> bits in the default model.
>
> Signed-off-by: Christian Borntraeger <address@hidden>
> ---
> hw/s390x/s390-virtio-ccw.c | 2 ++
> target/s390x/gen-features.c | 2 ++
> 2 files changed, 4 insertions(+)
>
> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
> index 7ae5fb38dd..f8f58c8acb 100644
> --- a/hw/s390x/s390-virtio-ccw.c
> +++ b/hw/s390x/s390-virtio-ccw.c
> @@ -824,6 +824,8 @@ DEFINE_CCW_MACHINE(3_0, "3.0", true);
> static void ccw_machine_2_12_instance_options(MachineState *machine)
> {
> ccw_machine_3_0_instance_options(machine);
> + s390_cpudef_featoff_greater(11, 1, S390_FEAT_PPA15);
> + s390_cpudef_featoff_greater(11, 1, S390_FEAT_BPB);
> }
>
> static void ccw_machine_2_12_class_options(MachineClass *mc)
> diff --git a/target/s390x/gen-features.c b/target/s390x/gen-features.c
> index 6c1c636140..5af042c003 100644
> --- a/target/s390x/gen-features.c
> +++ b/target/s390x/gen-features.c
> @@ -513,6 +513,8 @@ static uint16_t default_GEN11_GA1[] = {
> S390_FEAT_IPTE_RANGE,
> S390_FEAT_ACCESS_EXCEPTION_FS_INDICATION,
> S390_FEAT_GROUP_MSA_EXT_4,
> + S390_FEAT_PPA15,
> + S390_FEAT_BPB,
> };
>
> #define default_GEN11_GA2 EmptyFeat
>
--
Thanks,
David / dhildenb