linux/virt/kvm
Thomas Huth a86cb413f4 KVM: s390: Do not report unusabled IDs via KVM_CAP_MAX_VCPU_ID
KVM_CAP_MAX_VCPU_ID is currently always reporting KVM_MAX_VCPU_ID on all
architectures. However, on s390x, the amount of usable CPUs is determined
during runtime - it is depending on the features of the machine the code
is running on. Since we are using the vcpu_id as an index into the SCA
structures that are defined by the hardware (see e.g. the sca_add_vcpu()
function), it is not only the amount of CPUs that is limited by the hard-
ware, but also the range of IDs that we can use.
Thus KVM_CAP_MAX_VCPU_ID must be determined during runtime on s390x, too.
So the handling of KVM_CAP_MAX_VCPU_ID has to be moved from the common
code into the architecture specific code, and on s390x we have to return
the same value here as for KVM_CAP_MAX_VCPUS.
This problem has been discovered with the kvm_create_max_vcpus selftest.
With this change applied, the selftest now passes on s390x, too.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20190523164309.13345-9-thuth@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2019-05-28 15:52:19 +02:00
..
arm KVM: s390: Do not report unusabled IDs via KVM_CAP_MAX_VCPU_ID 2019-05-28 15:52:19 +02:00
async_pf.c KVM: fix some typos 2018-12-21 11:28:26 +01:00
async_pf.h KVM: fix checkpatch.pl errors in kvm/async_pf.h 2015-06-19 17:16:25 +02:00
coalesced_mmio.c kvm: Add memcg accounting to KVM allocations 2019-02-20 22:48:29 +01:00
coalesced_mmio.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
eventfd.c kvm: Check irqchip mode before assign irqfd 2019-05-24 21:27:12 +02:00
irqchip.c KVM: fix spectrev1 gadgets 2019-04-16 15:38:07 +02:00
Kconfig KVM: polling: add architecture backend to disable polling 2019-04-26 09:08:17 +02:00
kvm_main.c KVM: s390: Do not report unusabled IDs via KVM_CAP_MAX_VCPU_ID 2019-05-28 15:52:19 +02:00
vfio.c kvm: Add memcg accounting to KVM allocations 2019-02-20 22:48:29 +01:00
vfio.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00