kernel/linux.git/include/uapi/linux/kvm.h, branch v5.7.3

KVM: PPC: Book3S HV: Add a capability for enabling secure guests

2020-03-26T00:09:04+00:00

At present, on Power systems with Protected Execution Facility hardware and an ultravisor, a KVM guest can transition to being a secure guest at will. Userspace (QEMU) has no way of knowing whether a host system is capable of running secure guests. This will present a problem in future when the ultravisor is capable of migrating secure guests from one host to another, because virtualization management software will have no way to ensure that secure guests only run in domains where all of the hosts can support secure guests. This adds a VM capability which has two functions: (a) userspace can query it to find out whether the host can support secure guests, and (b) userspace can enable it for a guest, which allows that guest to become a secure guest. If userspace does not enable it, KVM will return an error when the ultravisor does the hypercall that indicates that the guest is starting to transition to a secure guest. The ultravisor will then abort the transition and the guest will terminate. Signed-off-by: Paul Mackerras Reviewed-by: David Gibson Reviewed-by: Ram Pai

Merge tag 'kvm-s390-next-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

2020-03-16T17:19:34+00:00

KVM: s390: Features and Enhancements for 5.7 part1 1. Allow to disable gisa 2. protected virtual machines Protected VMs (PVM) are KVM VMs, where KVM can't access the VM's state like guest memory and guest registers anymore. Instead the PVMs are mostly managed by a new entity called Ultravisor (UV), which provides an API, so KVM and the PV can request management actions. PVMs are encrypted at rest and protected from hypervisor access while running. They switch from a normal operation into protected mode, so we can still use the standard boot process to load a encrypted blob and then move it into protected mode. Rebooting is only possible by passing through the unprotected/normal mode and switching to protected again. One mm related patch will go via Andrews mm tree ( mm/gup/writeback: add callbacks for inaccessible pages)

KVM: x86: enable dirty log gradually in small chunks

2020-03-16T16:57:37+00:00

It could take kvm->mmu_lock for an extended period of time when enabling dirty log for the first time. The main cost is to clear all the D-bits of last level SPTEs. This situation can benefit from manual dirty log protect as well, which can reduce the mmu_lock time taken. The sequence is like this: 1. Initialize all the bits of the dirty bitmap to 1 when enabling dirty log for the first time 2. Only write protect the huge pages 3. KVM_GET_DIRTY_LOG returns the dirty bitmap info 4. KVM_CLEAR_DIRTY_LOG will clear D-bit for each of the leaf level SPTEs gradually in small chunks Under the Intel(R) Xeon(R) Gold 6152 CPU @ 2.10GHz environment, I did some tests with a 128G windows VM and counted the time taken of memory_global_dirty_log_start, here is the numbers: VM Size Before After optimization 128G 460ms 10ms Signed-off-by: Jay Zhou Signed-off-by: Paolo Bonzini

KVM: s390: protvirt: introduce and enable KVM_CAP_S390_PROTECTED

2020-02-27T18:47:13+00:00

Now that everything is in place, we can announce the feature. Signed-off-by: Christian Borntraeger Reviewed-by: Cornelia Huck Reviewed-by: David Hildenbrand

KVM: s390: protvirt: UV calls in support of diag308 0, 1

2020-02-27T18:47:12+00:00

diag 308 subcode 0 and 1 require several KVM and Ultravisor interactions. Specific to these "soft" reboots are * The "unshare all" UVC * The "prepare for reset" UVC Signed-off-by: Janosch Frank Acked-by: David Hildenbrand Reviewed-by: Cornelia Huck [borntraeger@de.ibm.com: patch merging, splitting, fixing] Signed-off-by: Christian Borntraeger

KVM: S390: protvirt: Introduce instruction data area bounce buffer

2020-02-27T18:47:11+00:00

Now that we can't access guest memory anymore, we have a dedicated satellite block that's a bounce buffer for instruction data. We re-use the memop interface to copy the instruction data to / from userspace. This lets us re-use a lot of QEMU code which used that interface to make logical guest memory accesses which are not possible anymore in protected mode anyway. Signed-off-by: Janosch Frank Reviewed-by: Thomas Huth Reviewed-by: David Hildenbrand [borntraeger@de.ibm.com: patch merging, splitting, fixing] Signed-off-by: Christian Borntraeger

KVM: s390: protvirt: Add initial vm and cpu lifecycle handling

2020-02-27T18:47:11+00:00

This contains 3 main changes: 1. changes in SIE control block handling for secure guests 2. helper functions for create/destroy/unpack secure guests 3. KVM_S390_PV_COMMAND ioctl to allow userspace dealing with secure machines Signed-off-by: Janosch Frank Reviewed-by: David Hildenbrand Reviewed-by: Cornelia Huck [borntraeger@de.ibm.com: patch merging, splitting, fixing] Signed-off-by: Christian Borntraeger

KVM: s390: Add new reset vcpu API

2020-01-31T11:50:04+00:00

The architecture states that we need to reset local IRQs for all CPU resets. Because the old reset interface did not support the normal CPU reset we never did that on a normal reset. Let's implement an interface for the missing normal and clear resets and reset all local IRQs, registers and control structures as stated in the architecture. Userspace might already reset the registers via the vcpu run struct, but as we need the interface for the interrupt clearing part anyway, we implement the resets fully and don't rely on userspace to reset the rest. Signed-off-by: Janosch Frank Reviewed-by: Cornelia Huck Reviewed-by: Christian Borntraeger Reviewed-by: Thomas Huth Link: https://lore.kernel.org/r/20200131100205.74720-4-frankja@linux.ibm.com Signed-off-by: Christian Borntraeger

KVM: PPC: Book3S HV: Support reset of secure guest

2019-11-28T06:02:31+00:00

Add support for reset of secure guest via a new ioctl KVM_PPC_SVM_OFF. This ioctl will be issued by QEMU during reset and includes the the following steps: - Release all device pages of the secure guest. - Ask UV to terminate the guest via UV_SVM_TERMINATE ucall - Unpin the VPA pages so that they can be migrated back to secure side when guest becomes secure again. This is required because pinned pages can't be migrated. - Reinit the partition scoped page tables After these steps, guest is ready to issue UV_ESM call once again to switch to secure mode. Signed-off-by: Bharata B Rao Signed-off-by: Sukadev Bhattiprolu [Implementation of uv_svm_terminate() and its call from guest shutdown path] Signed-off-by: Ram Pai [Unpinning of VPA pages] Signed-off-by: Paul Mackerras

Merge tag 'kvmarm-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2019-11-21T08:58:35+00:00

KVM/arm updates for Linux 5.5: - Allow non-ISV data aborts to be reported to userspace - Allow injection of data aborts from userspace - Expose stolen time to guests - GICv4 performance improvements - vgic ITS emulation fixes - Simplify FWB handling - Enable halt pool counters - Make the emulated timer PREEMPT_RT compliant Conflicts: include/uapi/linux/kvm.h