Starting with recent kernels, if the cmma attributes are available, we
actually have hardware support. Enabling CMMA then means providing the
guest VCPU with CMM, therefore enabling its CMM facility.
Let's not blindly enable CMM anymore but let's control it using CPU models.
For disabled CPU models, CMMA will continue to always get enabled.
Also enable it in the applicable default models.
Please note that CMM doesn't work with hugetlbfs, therefore we will
warn the user and keep it disabled. Migrating from/to a hugetlbfs
configuration works, as it will be disabled on both sides.
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Message-Id: <20160905085244.99980-24-dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Feature groups will be very helpful to reduce the amount of features
typically available in sane configurations. E.g. the MSA facilities
introduced loads of subfunctions, which could - in theory - go away
in the future, but we want to avoid reporting hundrets of features to
the user if usually all of them are in place.
Groups only contain features that were introduced in one shot, not just
random features. Therefore, groups can never change. This is an important
property regarding migration.
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Message-Id: <20160905085244.99980-7-dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
This patch introduces the helper "gen-features" which allows to generate
feature list definitions at compile time. Its flexibility is better and the
error-proneness is lower when compared to static programming time added
statements.
The helper includes "target-s390x/cpu_features.h" to be able to use named
facility bits instead of numbers. The generated defines will be used for
the definition of CPU models.
We generate feature lists for each HW generation and GA for EC models. BC
models are always based on a EC version and have no separate definitions.
Base features: Features we expect to be always available in sane setups.
Migration safe - will never change. Can be seen as "minimum features
required for a CPU model".
Default features: Features we expect to be stable and around in latest
setups (e.g. having KVM support) - not migration safe.
Max features: All supported features that are theoretically allowed for a
CPU model. Exceeding these features could otherwise produce problems with
IBC (instruction blocking controls) in KVM.
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
[generate base, default and models. renaming and cleanup]
Message-Id: <20160905085244.99980-6-dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
