kernel.git/Documentation/virt/kvm/api.rst, branch linux-5.16.y

KVM: x86: Add KVM_CAP_ENABLE_CAP to x86

2022-03-08T18:14:05Z

[ Upstream commit 127770ac0d043435375ab86434f31a93efa88215 ] Follow the precedent set by other architectures that support the VCPU ioctl, KVM_ENABLE_CAP, and advertise the VM extension, KVM_CAP_ENABLE_CAP. This way, userspace can ensure that KVM_ENABLE_CAP is available on a vcpu before using it. Fixes: 5c919412fe61 ("kvm/x86: Hyper-V synthetic interrupt controller") Signed-off-by: Aaron Lewis Message-Id: <20220214212950.1776943-1-aaronlewis@google.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin

KVM: SEV: Add support for SEV intra host migration

2021-11-11T15:35:27Z

For SEV to work with intra host migration, contents of the SEV info struct such as the ASID (used to index the encryption key in the AMD SP) and the list of memory regions need to be transferred to the target VM. This change adds a commands for a target VMM to get a source SEV VM's sev info. Signed-off-by: Peter Gonda Suggested-by: Sean Christopherson Reviewed-by: Marc Orr Cc: Marc Orr Cc: Paolo Bonzini Cc: Sean Christopherson Cc: David Rientjes Cc: Dr. David Alan Gilbert Cc: Brijesh Singh Cc: Tom Lendacky Cc: Vitaly Kuznetsov Cc: Wanpeng Li Cc: Jim Mattson Cc: Joerg Roedel Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: "H. Peter Anvin" Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Message-Id: <20211021174303.385706-3-pgonda@google.com> Signed-off-by: Paolo Bonzini

KVM: x86: Report host tsc and realtime values in KVM_GET_CLOCK

2021-10-18T18:43:44Z

Handling the migration of TSCs correctly is difficult, in part because Linux does not provide userspace with the ability to retrieve a (TSC, realtime) clock pair for a single instant in time. In lieu of a more convenient facility, KVM can report similar information in the kvm_clock structure. Provide userspace with a host TSC & realtime pair iff the realtime clock is based on the TSC. If userspace provides KVM_SET_CLOCK with a valid realtime value, advance the KVM clock by the amount of elapsed time. Do not step the KVM clock backwards, though, as it is a monotonic oscillator. Suggested-by: Paolo Bonzini Signed-off-by: Oliver Upton Signed-off-by: Paolo Bonzini Message-Id: <20210916181538.968978-5-oupton@google.com> Signed-off-by: Paolo Bonzini

RISC-V: KVM: Document RISC-V specific parts of KVM API

2021-10-04T10:42:34Z

Document RISC-V specific parts of the KVM API, such as: - The interrupt numbers passed to the KVM_INTERRUPT ioctl. - The states supported by the KVM_{GET,SET}_MP_STATE ioctls. - The registers supported by the KVM_{GET,SET}_ONE_REG interface and the encoding of those register ids. - The exit reason KVM_EXIT_RISCV_SBI for SBI calls forwarded to userspace tool. CC: Jonathan Corbet CC: linux-doc@vger.kernel.org Signed-off-by: Anup Patel Acked-by: Palmer Dabbelt

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2021-09-07T20:40:51Z

Pull KVM updates from Paolo Bonzini: "ARM: - Page ownership tracking between host EL1 and EL2 - Rely on userspace page tables to create large stage-2 mappings - Fix incompatibility between pKVM and kmemleak - Fix the PMU reset state, and improve the performance of the virtual PMU - Move over to the generic KVM entry code - Address PSCI reset issues w.r.t. save/restore - Preliminary rework for the upcoming pKVM fixed feature - A bunch of MM cleanups - a vGIC fix for timer spurious interrupts - Various cleanups s390: - enable interpretation of specification exceptions - fix a vcpu_idx vs vcpu_id mixup x86: - fast (lockless) page fault support for the new MMU - new MMU now the default - increased maximum allowed VCPU count - allow inhibit IRQs on KVM_RUN while debugging guests - let Hyper-V-enabled guests run with virtualized LAPIC as long as they do not enable the Hyper-V "AutoEOI" feature - fixes and optimizations for the toggling of AMD AVIC (virtualized LAPIC) - tuning for the case when two-dimensional paging (EPT/NPT) is disabled - bugfixes and cleanups, especially with respect to vCPU reset and choosing a paging mode based on CR0/CR4/EFER - support for 5-level page table on AMD processors Generic: - MMU notifier invalidation callbacks do not take mmu_lock unless necessary - improved caching of LRU kvm_memory_slot - support for histogram statistics - add statistics for halt polling and remote TLB flush requests" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (210 commits) KVM: Drop unused kvm_dirty_gfn_invalid() KVM: x86: Update vCPU's hv_clock before back to guest when tsc_offset is adjusted KVM: MMU: mark role_regs and role accessors as maybe unused KVM: MIPS: Remove a "set but not used" variable x86/kvm: Don't enable IRQ when IRQ enabled in kvm_wait KVM: stats: Add VM stat for remote tlb flush requests KVM: Remove unnecessary export of kvm_{inc,dec}_notifier_count() KVM: x86/mmu: Move lpage_disallowed_link further "down" in kvm_mmu_page KVM: x86/mmu: Relocate kvm_mmu_page.tdp_mmu_page for better cache locality Revert "KVM: x86: mmu: Add guest physical address check in translate_gpa()" KVM: x86/mmu: Remove unused field mmio_cached in struct kvm_mmu_page kvm: x86: Increase KVM_SOFT_MAX_VCPUS to 710 kvm: x86: Increase MAX_VCPUS to 1024 kvm: x86: Set KVM_MAX_VCPU_ID to 4*KVM_MAX_VCPUS KVM: VMX: avoid running vmx_handle_exit_irqoff in case of emulation KVM: x86/mmu: Don't freak out if pml5_root is NULL on 4-level host KVM: s390: index kvm->arch.idle_mask by vcpu_idx KVM: s390: Enable specification exception interpretation KVM: arm64: Trim guest debug exception handling KVM: SVM: Add 5-level page table support for SVM ...

Merge tag 'docs-5.15' of git://git.lwn.net/linux

2021-09-02T01:49:47Z

Pull documentation updates from Jonathan Corbet: "Yet another set of documentation changes: - A reworking of PDF generation to yield better results for documents using CJK fonts in particular. - A new set of translations into traditional Chinese, a dialect for which I am assured there is a community of interested readers. - A lot more regular Chinese translation work as well. ... plus the usual assortment of updates, fixes, typo tweaks, etc" * tag 'docs-5.15' of git://git.lwn.net/linux: (55 commits) docs: sphinx-requirements: Move sphinx_rtd_theme to top docs: pdfdocs: Enable language-specific font choice of zh_TW translations docs: pdfdocs: Teach xeCJK about character classes of quotation marks docs: pdfdocs: Permit AutoFakeSlant for CJK fonts docs: pdfdocs: One-half spacing for CJK translations docs: pdfdocs: Add conf.py local to translations for ascii-art alignment docs: pdfdocs: Preserve inter-phrase space in Korean translations docs: pdfdocs: Choose Serif font as CJK mainfont if possible docs: pdfdocs: Add CJK-language-specific font settings docs: pdfdocs: Refactor config for CJK document scripts/kernel-doc: Override -Werror from KCFLAGS with KDOC_WERROR docs/zh_CN: Add zh_CN/accounting/psi.rst doc: align Italian translation Documentation/features/vm: riscv supports THP now docs/zh_CN: add infiniband user_verbs translation docs/zh_CN: add infiniband user_mad translation docs/zh_CN: add infiniband tag_matching translation docs/zh_CN: add infiniband sysfs translation docs/zh_CN: add infiniband opa_vnic translation docs/zh_CN: add infiniband ipoib translation ...

KVM: x86: implement KVM_GUESTDBG_BLOCKIRQ

2021-08-20T20:06:37Z

KVM_GUESTDBG_BLOCKIRQ will allow KVM to block all interrupts while running. This change is mostly intended for more robust single stepping of the guest and it has the following benefits when enabled: * Resuming from a breakpoint is much more reliable. When resuming execution from a breakpoint, with interrupts enabled, more often than not, KVM would inject an interrupt and make the CPU jump immediately to the interrupt handler and eventually return to the breakpoint, to trigger it again. From the user point of view it looks like the CPU never executed a single instruction and in some cases that can even prevent forward progress, for example, when the breakpoint is placed by an automated script (e.g lx-symbols), which does something in response to the breakpoint and then continues the guest automatically. If the script execution takes enough time for another interrupt to arrive, the guest will be stuck on the same breakpoint RIP forever. * Normal single stepping is much more predictable, since it won't land the debugger into an interrupt handler. * RFLAGS.TF has less chance to be leaked to the guest: We set that flag behind the guest's back to do single stepping but if single step lands us into an interrupt/exception handler it will be leaked to the guest in the form of being pushed to the stack. This doesn't completely eliminate this problem as exceptions can still happen, but at least this reduces the chances of this happening. Signed-off-by: Maxim Levitsky Message-Id: <20210811122927.900604-6-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini

KVM: stats: Update doc for histogram statistics

2021-08-20T20:06:32Z

Add documentations for linear and logarithmic histogram statistics. Signed-off-by: Jing Zhang Message-Id: <20210802165633.1866976-3-jingzhangos@google.com> [Small changes to the phrasing. - Paolo] Signed-off-by: Paolo Bonzini

docs: virt: kvm: api.rst: replace some characters

2021-07-26T12:26:06Z

The conversion tools used during DocBook/LaTeX/html/Markdown->ReST conversion and some cut-and-pasted text contain some characters that aren't easily reachable on standard keyboards and/or could cause troubles when parsed by the documentation build system. Replace the occurences of the following characters: - U+00a0 (' '): NO-BREAK SPACE as it can cause lines being truncated on PDF output Signed-off-by: Mauro Carvalho Chehab Message-Id: Signed-off-by: Paolo Bonzini

KVM: Documentation: Fix KVM_CAP_ENFORCE_PV_FEATURE_CPUID name

2021-07-26T12:24:30Z

'KVM_CAP_ENFORCE_PV_CPUID' doesn't match the define in include/uapi/linux/kvm.h. Signed-off-by: Vitaly Kuznetsov Message-Id: <20210722092628.236474-1-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini