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| author | Christian Borntraeger <borntraeger@de.ibm.com> | 2017-11-09 10:00:45 +0100 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2017-11-09 16:48:51 +0100 |
| commit | da9a1446d248f673a8560ce46251ff620214ab7b (patch) | |
| tree | 1ad9a5e7c71c4c31536e0a532339ec759a2ad0e8 /Documentation/virtual | |
| parent | 4dd6f17eb913d3d23dd6c07950627ac2c3068dca (diff) | |
| download | lwn-da9a1446d248f673a8560ce46251ff620214ab7b.tar.gz lwn-da9a1446d248f673a8560ce46251ff620214ab7b.zip | |
KVM: s390: provide a capability for AIS state migration
The AIS capability was introduced in 4.12, while the interface to
migrate the state was added in 4.13. Unfortunately it is not possible
for userspace to detect the migration capability without creating a flic
kvm device. As in QEMU the cpu model detection runs on the "none"
machine this will result in cpu model issues regarding the "ais"
capability.
To get the "ais" capability properly let's add a new KVM capability that
tells userspace that AIS states can be migrated.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Diffstat (limited to 'Documentation/virtual')
| -rw-r--r-- | Documentation/virtual/kvm/api.txt | 9 | ||||
| -rw-r--r-- | Documentation/virtual/kvm/devices/s390_flic.txt | 2 |
2 files changed, 11 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index e63a35fafef0..49540e53c4bd 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -4347,3 +4347,12 @@ This capability indicates that userspace can load HV_X64_MSR_VP_INDEX msr. Its value is used to denote the target vcpu for a SynIC interrupt. For compatibilty, KVM initializes this msr to KVM's internal vcpu index. When this capability is absent, userspace can still query this msr's value. + +8.13 KVM_CAP_S390_AIS_MIGRATION + +Architectures: s390 +Parameters: none + +This capability indicates if the flic device will be able to get/set the +AIS states for migration via the KVM_DEV_FLIC_AISM_ALL attribute and allows +to discover this without having to create a flic device. diff --git a/Documentation/virtual/kvm/devices/s390_flic.txt b/Documentation/virtual/kvm/devices/s390_flic.txt index 27ad53c7149d..a4e20a090174 100644 --- a/Documentation/virtual/kvm/devices/s390_flic.txt +++ b/Documentation/virtual/kvm/devices/s390_flic.txt @@ -151,6 +151,8 @@ struct kvm_s390_ais_all { to an ISC (MSB0 bit 0 to ISC 0 and so on). The combination of simm bit and nimm bit presents AIS mode for a ISC. + KVM_DEV_FLIC_AISM_ALL is indicated by KVM_CAP_S390_AIS_MIGRATION. + Note: The KVM_SET_DEVICE_ATTR/KVM_GET_DEVICE_ATTR device ioctls executed on FLIC with an unknown group or attribute gives the error code EINVAL (instead of ENXIO, as specified in the API documentation). It is not possible to conclude |