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* Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2020-06-031-1/+40
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kvm updates from Paolo Bonzini: "ARM: - Move the arch-specific code into arch/arm64/kvm - Start the post-32bit cleanup - Cherry-pick a few non-invasive pre-NV patches x86: - Rework of TLB flushing - Rework of event injection, especially with respect to nested virtualization - Nested AMD event injection facelift, building on the rework of generic code and fixing a lot of corner cases - Nested AMD live migration support - Optimization for TSC deadline MSR writes and IPIs - Various cleanups - Asynchronous page fault cleanups (from tglx, common topic branch with tip tree) - Interrupt-based delivery of asynchronous "page ready" events (host side) - Hyper-V MSRs and hypercalls for guest debugging - VMX preemption timer fixes s390: - Cleanups Generic: - switch vCPU thread wakeup from swait to rcuwait The other architectures, and the guest side of the asynchronous page fault work, will come next week" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (256 commits) KVM: selftests: fix rdtsc() for vmx_tsc_adjust_test KVM: check userspace_addr for all memslots KVM: selftests: update hyperv_cpuid with SynDBG tests x86/kvm/hyper-v: Add support for synthetic debugger via hypercalls x86/kvm/hyper-v: enable hypercalls regardless of hypercall page x86/kvm/hyper-v: Add support for synthetic debugger interface x86/hyper-v: Add synthetic debugger definitions KVM: selftests: VMX preemption timer migration test KVM: nVMX: Fix VMX preemption timer migration x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit KVM: x86/pmu: Support full width counting KVM: x86/pmu: Tweak kvm_pmu_get_msr to pass 'struct msr_data' in KVM: x86: announce KVM_FEATURE_ASYNC_PF_INT KVM: x86: acknowledgment mechanism for async pf page ready notifications KVM: x86: interrupt based APF 'page ready' event delivery KVM: introduce kvm_read_guest_offset_cached() KVM: rename kvm_arch_can_inject_async_page_present() to kvm_arch_can_dequeue_async_page_present() KVM: x86: extend struct kvm_vcpu_pv_apf_data with token info Revert "KVM: async_pf: Fix #DF due to inject "Page not Present" and "Page Ready" exceptions simultaneously" KVM: VMX: Replace zero-length array with flexible-array ...
| * Merge tag 'kvmarm-5.8' of ↵Paolo Bonzini2020-06-011-1/+1
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for Linux 5.8: - Move the arch-specific code into arch/arm64/kvm - Start the post-32bit cleanup - Cherry-pick a few non-invasive pre-NV patches
| | * KVM: arm64: Support enabling dirty log gradually in small chunksKeqian Zhu2020-05-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is already support of enabling dirty log gradually in small chunks for x86 in commit 3c9bd4006bfc ("KVM: x86: enable dirty log gradually in small chunks"). This adds support for arm64. x86 still writes protect all huge pages when DIRTY_LOG_INITIALLY_ALL_SET is enabled. However, for arm64, both huge pages and normal pages can be write protected gradually by userspace. Under the Huawei Kunpeng 920 2.6GHz platform, I did some tests on 128G Linux VMs with different page size. The memory pressure is 127G in each case. The time taken of memory_global_dirty_log_start in QEMU is listed below: Page Size Before After Optimization 4K 650ms 1.8ms 2M 4ms 1.8ms 1G 2ms 1.8ms Besides the time reduction, the biggest improvement is that we will minimize the performance side effect (because of dissolving huge pages and marking memslots dirty) on guest after enabling dirty log. Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200413122023.52583-1-zhukeqian1@huawei.com
| * | x86/kvm/hyper-v: Add support for synthetic debugger interfaceJon Doron2020-06-011-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add support for Hyper-V synthetic debugger (syndbg) interface. The syndbg interface is using MSRs to emulate a way to send/recv packets data. The debug transport dll (kdvm/kdnet) will identify if Hyper-V is enabled and if it supports the synthetic debugger interface it will attempt to use it, instead of trying to initialize a network adapter. Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Jon Doron <arilou@gmail.com> Message-Id: <20200529134543.1127440-4-arilou@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | KVM: nVMX: Fix VMX preemption timer migrationPeter Shier2020-06-011-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add new field to hold preemption timer expiration deadline appended to struct kvm_vmx_nested_state_hdr. This is to prevent the first VM-Enter after migration from incorrectly restarting the timer with the full timer value instead of partially decayed timer value. KVM_SET_NESTED_STATE restarts timer using migrated state regardless of whether L1 sets VM_EXIT_SAVE_VMX_PREEMPTION_TIMER. Fixes: cf8b84f48a593 ("kvm: nVMX: Prepare for checkpointing L2 state") Signed-off-by: Peter Shier <pshier@google.com> Signed-off-by: Makarand Sonare <makarandsonare@google.com> Message-Id: <20200526215107.205814-2-makarandsonare@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exitJon Doron2020-06-011-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The problem the patch is trying to address is the fact that 'struct kvm_hyperv_exit' has different layout on when compiling in 32 and 64 bit modes. In 64-bit mode the default alignment boundary is 64 bits thus forcing extra gaps after 'type' and 'msr' but in 32-bit mode the boundary is at 32 bits thus no extra gaps. This is an issue as even when the kernel is 64 bit, the userspace using the interface can be both 32 and 64 bit but the same 32 bit userspace has to work with 32 bit kernel. The issue is fixed by forcing the 64 bit layout, this leads to ABI change for 32 bit builds and while we are obviously breaking '32 bit userspace with 32 bit kernel' case, we're fixing the '32 bit userspace with 64 bit kernel' one. As the interface has no (known) users and 32 bit KVM is rather baroque nowadays, this seems like a reasonable decision. Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Jon Doron <arilou@gmail.com> Message-Id: <20200424113746.3473563-2-arilou@gmail.com> Reviewed-by: Roman Kagan <rvkagan@yandex-team.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | kvm: add capability for halt pollingDavid Matlack2020-04-241-0/+17
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KVM_CAP_HALT_POLL is a per-VM capability that lets userspace control the halt-polling time, allowing halt-polling to be tuned or disabled on particular VMs. With dynamic halt-polling, a VM's VCPUs can poll from anywhere from [0, halt_poll_ns] on each halt. KVM_CAP_HALT_POLL sets the upper limit on the poll time. Signed-off-by: David Matlack <dmatlack@google.com> Signed-off-by: Jon Cargille <jcargill@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Message-Id: <20200417221446.108733-1-jcargill@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* / docs: kvm: Fix KVM_KVMCLOCK_CTRL API docJoshua Abraham2020-05-051-5/+7
|/ | | | | | | | | | The KVM_KVMCLOCK_CTRL ioctl signals to supported KVM guests that the hypervisor has paused it. Update the documentation to reflect that the guest is notified by this API. Signed-off-by: Joshua Abraham <sinisterpatrician@gmail.com> Link: https://lore.kernel.org/r/20200501223624.GA25826@josh-ZenBook Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* Merge tag 'kvm-ppc-next-5.7-1' of ↵Paolo Bonzini2020-03-311-0/+17
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD KVM PPC update for 5.7 * Add a capability for enabling secure guests under the Protected Execution Framework ultravisor * Various bug fixes and cleanups.
| * KVM: PPC: Book3S HV: Add a capability for enabling secure guestsPaul Mackerras2020-03-261-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <paulus@ozlabs.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Ram Pai <linuxram@us.ibm.com>
* | Merge tag 'kvm-s390-next-5.7-3' of ↵Paolo Bonzini2020-03-301-0/+6
|\ \ | |/ |/| | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD KVM: s390: Fix for error codes - return the proper error to userspace when a signal interrupts the KSM unsharing operation
| * s390/gmap: return proper error code on ksm unsharingChristian Borntraeger2020-03-271-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a signal is pending we might return -ENOMEM instead of -EINTR. We should propagate the proper error during KSM unsharing. unmerge_ksm_pages returns -ERESTARTSYS on signal_pending. This gets translated by entry.S to -EINTR. It is important to get this error code so that userspace can retry. To make this clearer we also add -EINTR to the documentation of the PV_ENABLE call, which calls unmerge_ksm_pages. Fixes: 3ac8e38015d4 ("s390/mm: disable KSM for storage key enabled pages") Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com> Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com> Tested-by: Marc Hartmayer <mhartmay@linux.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | Merge tag 'kvm-s390-next-5.7-1' of ↵Paolo Bonzini2020-03-161-2/+63
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD 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: s390: protvirt: Add KVM api documentationJanosch Frank2020-02-271-0/+59
| | | | | | | | | | | | | | | | | | | | Add documentation for KVM_CAP_S390_PROTECTED capability and the KVM_S390_PV_COMMAND ioctl. Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> [borntraeger@de.ibm.com: patch merging, splitting, fixing] Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * KVM: s390: protvirt: disallow one_regJanosch Frank2020-02-271-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A lot of the registers are controlled by the Ultravisor and never visible to KVM. Some fields in the sie control block are overlayed, like gbea. As no known userspace uses the ONE_REG interface on s390 if sync regs are available, no functionality is lost if it is disabled for protected guests. Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> [borntraeger@de.ibm.com: patch merging, splitting, fixing] Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: x86: Remove stateful CPUID handlingSean Christopherson2020-03-161-18/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the code for handling stateful CPUID 0x2 and mark the associated flags as deprecated. WARN if host CPUID 0x2.0.AL > 1, i.e. if by some miracle a host with stateful CPUID 0x2 is encountered. No known CPU exists that supports hardware accelerated virtualization _and_ a stateful CPUID 0x2. Barring an extremely contrived nested virtualization scenario, stateful CPUID support is dead code. Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: x86: enable dirty log gradually in small chunksJay Zhou2020-03-161-3/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <jianjay.zhou@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: s390: rstify new ioctls in api.rstChristian Borntraeger2020-02-241-15/+18
|/ | | | | | | | | | We also need to rstify the new ioctls that we added in parallel to the rstification of the kvm docs. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* docs: kvm: Convert api.txt to ReST formatMauro Carvalho Chehab2020-02-121-0/+6026
convert api.txt document to ReST format while trying to keep its format as close as possible with the authors intent, and avoid adding uneeded markups. - Use document title and chapter markups; - Convert tables; - Add markups for literal blocks; - use :field: for field descriptions; - Add blank lines and adjust indentation Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>