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authorPaolo Bonzini <pbonzini@redhat.com>2015-02-09 13:34:43 +0100
committerPaolo Bonzini <pbonzini@redhat.com>2015-02-09 13:34:43 +0100
commitccd9e785ea174a1c21d4c63a2afaacd6ef31d56d (patch)
tree33413aecd118bb8342e95ad3297a06ce322c07a0 /Documentation
parentf7819512996361280b86259222456fcf15aad926 (diff)
parentde8e5d744051568c8aad35c1c2dcf8fd137d10c9 (diff)
Merge tag 'kvm-s390-next-20150209' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
KVM: s390: fixes and features for kvm/next (3.20) 1. Fixes - Fix user triggerable endless loop - reenable LPP facility - disable KVM compat ioctl on s390 (untested and broken) 2. cpu models for s390 - provide facilities and instruction blocking per VM - add s390 specific vm attributes for setting values 3. crypto - toleration patch for z13 support 4. add uuid and long name to /proc/sysinfo (stsi 322) - patch Acked by Heiko Carstens (touches non-kvm s390 code)
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/virtual/kvm/devices/vm.txt45
1 files changed, 45 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/devices/vm.txt b/Documentation/virtual/kvm/devices/vm.txt
index c3b17c61b7dd..5542c4641a3c 100644
--- a/Documentation/virtual/kvm/devices/vm.txt
+++ b/Documentation/virtual/kvm/devices/vm.txt
@@ -38,3 +38,48 @@ Allows userspace to query the actual limit and set a new limit for
the maximum guest memory size. The limit will be rounded up to
2048 MB, 4096 GB, 8192 TB respectively, as this limit is governed by
the number of page table levels.
+
+2. GROUP: KVM_S390_VM_CPU_MODEL
+Architectures: s390
+
+2.1. ATTRIBUTE: KVM_S390_VM_CPU_MACHINE (r/o)
+
+Allows user space to retrieve machine and kvm specific cpu related information:
+
+struct kvm_s390_vm_cpu_machine {
+ __u64 cpuid; # CPUID of host
+ __u32 ibc; # IBC level range offered by host
+ __u8 pad[4];
+ __u64 fac_mask[256]; # set of cpu facilities enabled by KVM
+ __u64 fac_list[256]; # set of cpu facilities offered by host
+}
+
+Parameters: address of buffer to store the machine related cpu data
+ of type struct kvm_s390_vm_cpu_machine*
+Returns: -EFAULT if the given address is not accessible from kernel space
+ -ENOMEM if not enough memory is available to process the ioctl
+ 0 in case of success
+
+2.2. ATTRIBUTE: KVM_S390_VM_CPU_PROCESSOR (r/w)
+
+Allows user space to retrieve or request to change cpu related information for a vcpu:
+
+struct kvm_s390_vm_cpu_processor {
+ __u64 cpuid; # CPUID currently (to be) used by this vcpu
+ __u16 ibc; # IBC level currently (to be) used by this vcpu
+ __u8 pad[6];
+ __u64 fac_list[256]; # set of cpu facilities currently (to be) used
+ # by this vcpu
+}
+
+KVM does not enforce or limit the cpu model data in any form. Take the information
+retrieved by means of KVM_S390_VM_CPU_MACHINE as hint for reasonable configuration
+setups. Instruction interceptions triggered by additionally set facilitiy bits that
+are not handled by KVM need to by imlemented in the VM driver code.
+
+Parameters: address of buffer to store/set the processor related cpu
+ data of type struct kvm_s390_vm_cpu_processor*.
+Returns: -EBUSY in case 1 or more vcpus are already activated (only in write case)
+ -EFAULT if the given address is not accessible from kernel space
+ -ENOMEM if not enough memory is available to process the ioctl
+ 0 in case of success