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2021-01-08Merge tag 'kvmarm-fixes-5.11-1' of ↵Paolo Bonzini1-2/+7
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 5.11, take #1 - VM init cleanups - PSCI relay cleanups - Kill CONFIG_KVM_ARM_PMU - Fixup __init annotations - Fixup reg_to_encoding() - Fix spurious PMCR_EL0 access
2020-12-23KVM: Documentation: Add arm64 KVM_RUN error codesAlexandru Elisei1-2/+7
The API documentation states that general error codes are not detailed, but errors with specific meanings are. On arm64, KVM_RUN can return error numbers with a different meaning than what is described by POSIX or the C99 standard (as taken from man 3 errno). Absent from the newly documented error codes is ERANGE which can be returned when making a change to the EL2 stage 1 tables if the address is larger than the largest supported input address. Assuming no bugs in the implementation, that is not possible because the input addresses which are mapped are the result of applying the macro kern_hyp_va() on kernel virtual addresses. CC: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20201201150157.223625-2-alexandru.elisei@arm.com
2020-11-15KVM: Make dirty ring exclusive to dirty bitmap logPeter Xu1-0/+7
There's no good reason to use both the dirty bitmap logging and the new dirty ring buffer to track dirty bits. We should be able to even support both of them at the same time, but it could complicate things which could actually help little. Let's simply make it the rule before we enable dirty ring on any arch, that we don't allow these two interfaces to be used together. The big world switch would be KVM_CAP_DIRTY_LOG_RING capability enablement. That's where we'll switch from the default dirty logging way to the dirty ring way. As long as kvm->dirty_ring_size is setup correctly, we'll once and for all switch to the dirty ring buffer mode for the current virtual machine. Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20201001012224.5818-1-peterx@redhat.com> [Change errno from EINVAL to ENXIO. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-15KVM: X86: Implement ring-based dirty memory trackingPeter Xu1-0/+93
This patch is heavily based on previous work from Lei Cao <lei.cao@stratus.com> and Paolo Bonzini <pbonzini@redhat.com>. [1] KVM currently uses large bitmaps to track dirty memory. These bitmaps are copied to userspace when userspace queries KVM for its dirty page information. The use of bitmaps is mostly sufficient for live migration, as large parts of memory are be dirtied from one log-dirty pass to another. However, in a checkpointing system, the number of dirty pages is small and in fact it is often bounded---the VM is paused when it has dirtied a pre-defined number of pages. Traversing a large, sparsely populated bitmap to find set bits is time-consuming, as is copying the bitmap to user-space. A similar issue will be there for live migration when the guest memory is huge while the page dirty procedure is trivial. In that case for each dirty sync we need to pull the whole dirty bitmap to userspace and analyse every bit even if it's mostly zeros. The preferred data structure for above scenarios is a dense list of guest frame numbers (GFN). This patch series stores the dirty list in kernel memory that can be memory mapped into userspace to allow speedy harvesting. This patch enables dirty ring for X86 only. However it should be easily extended to other archs as well. [1] https://patchwork.kernel.org/patch/10471409/ Signed-off-by: Lei Cao <lei.cao@stratus.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20201001012222.5767-1-peterx@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-15KVM: x86: hyper-v: allow KVM_GET_SUPPORTED_HV_CPUID as a system ioctlVitaly Kuznetsov1-5/+11
KVM_GET_SUPPORTED_HV_CPUID is a vCPU ioctl but its output is now independent from vCPU and in some cases VMMs may want to use it as a system ioctl instead. In particular, QEMU doesn CPU feature expansion before any vCPU gets created so KVM_GET_SUPPORTED_HV_CPUID can't be used. Convert KVM_GET_SUPPORTED_HV_CPUID to 'dual' system/vCPU ioctl with the same meaning. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20200929150944.1235688-2-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-08KVM: Documentation: Update entry for KVM_CAP_ENFORCE_PV_CPUIDPeter Xu1-2/+1
Should be squashed into 66570e966dd9cb4f. Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20201023183358.50607-3-peterx@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-08KVM: Documentation: Update entry for KVM_X86_SET_MSR_FILTERPeter Xu1-1/+1
It should be an accident when rebase, since we've already have section 8.25 (which is KVM_CAP_S390_DIAG318). Fix the number. Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20201001012044.5151-2-peterx@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-23Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-9/+207
Pull KVM updates from Paolo Bonzini: "For x86, there is a new alternative and (in the future) more scalable implementation of extended page tables that does not need a reverse map from guest physical addresses to host physical addresses. For now it is disabled by default because it is still lacking a few of the existing MMU's bells and whistles. However it is a very solid piece of work and it is already available for people to hammer on it. Other updates: ARM: - New page table code for both hypervisor and guest stage-2 - Introduction of a new EL2-private host context - Allow EL2 to have its own private per-CPU variables - Support of PMU event filtering - Complete rework of the Spectre mitigation PPC: - Fix for running nested guests with in-kernel IRQ chip - Fix race condition causing occasional host hard lockup - Minor cleanups and bugfixes x86: - allow trapping unknown MSRs to userspace - allow userspace to force #GP on specific MSRs - INVPCID support on AMD - nested AMD cleanup, on demand allocation of nested SVM state - hide PV MSRs and hypercalls for features not enabled in CPUID - new test for MSR_IA32_TSC writes from host and guest - cleanups: MMU, CPUID, shared MSRs - LAPIC latency optimizations ad bugfixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (232 commits) kvm: x86/mmu: NX largepage recovery for TDP MMU kvm: x86/mmu: Don't clear write flooding count for direct roots kvm: x86/mmu: Support MMIO in the TDP MMU kvm: x86/mmu: Support write protection for nesting in tdp MMU kvm: x86/mmu: Support disabling dirty logging for the tdp MMU kvm: x86/mmu: Support dirty logging for the TDP MMU kvm: x86/mmu: Support changed pte notifier in tdp MMU kvm: x86/mmu: Add access tracking for tdp_mmu kvm: x86/mmu: Support invalidate range MMU notifier for TDP MMU kvm: x86/mmu: Allocate struct kvm_mmu_pages for all pages in TDP MMU kvm: x86/mmu: Add TDP MMU PF handler kvm: x86/mmu: Remove disallowed_hugepage_adjust shadow_walk_iterator arg kvm: x86/mmu: Support zapping SPTEs in the TDP MMU KVM: Cache as_id in kvm_memory_slot kvm: x86/mmu: Add functions to handle changed TDP SPTEs kvm: x86/mmu: Allocate and free TDP MMU roots kvm: x86/mmu: Init / Uninit the TDP MMU kvm: x86/mmu: Introduce tdp_iter KVM: mmu: extract spte.h and spte.c KVM: mmu: Separate updating a PTE from kvm_set_pte_rmapp ...
2020-10-22kvm: x86: only provide PV features if enabled in guest's CPUIDOliver Upton1-0/+11
KVM unconditionally provides PV features to the guest, regardless of the configured CPUID. An unwitting guest that doesn't check KVM_CPUID_FEATURES before use could access paravirt features that userspace did not intend to provide. Fix this by checking the guest's CPUID before performing any paravirtual operations. Introduce a capability, KVM_CAP_ENFORCE_PV_FEATURE_CPUID, to gate the aforementioned enforcement. Migrating a VM from a host w/o this patch to a host with this patch could silently change the ABI exposed to the guest, warranting that we default to the old behavior and opt-in for the new one. Reviewed-by: Jim Mattson <jmattson@google.com> Reviewed-by: Peter Shier <pshier@google.com> Signed-off-by: Oliver Upton <oupton@google.com> Change-Id: I202a0926f65035b872bfe8ad15307c026de59a98 Message-Id: <20200818152429.1923996-4-oupton@google.com> Reviewed-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-22KVM: VMX: Forbid userspace MSR filters for x2APICPaolo Bonzini1-8/+10
Allowing userspace to intercept reads to x2APIC MSRs when APICV is fully enabled for the guest simply can't work. But more in general, the LAPIC could be set to in-kernel after the MSR filter is setup and allowing accesses by userspace would be very confusing. We could in principle allow userspace to intercept reads and writes to TPR, and writes to EOI and SELF_IPI, but while that could be made it work, it would still be silly. Cc: Alexander Graf <graf@amazon.com> Cc: Aaron Lewis <aaronlewis@google.com> Cc: Peter Xu <peterx@redhat.com> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-22KVM: VMX: Ignore userspace MSR filters for x2APICSean Christopherson1-11/+16
Rework the resetting of the MSR bitmap for x2APIC MSRs to ignore userspace filtering. Allowing userspace to intercept reads to x2APIC MSRs when APICV is fully enabled for the guest simply can't work; the LAPIC and thus virtual APIC is in-kernel and cannot be directly accessed by userspace. To keep things simple we will in fact forbid intercepting x2APIC MSRs altogether, independent of the default_allow setting. Cc: Alexander Graf <graf@amazon.com> Cc: Aaron Lewis <aaronlewis@google.com> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20201005195532.8674-3-sean.j.christopherson@intel.com> [Modified to operate even if APICv is disabled, adjust documentation. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-13Merge tag 'docs-5.10' of git://git.lwn.net/linuxLinus Torvalds1-2/+2
Pull documentation updates from Jonathan Corbet: "As hoped, things calmed down for docs this cycle; fewer changes and almost no conflicts at all. This includes: - A reworked and expanded user-mode Linux document - Some simplifications and improvements for submitting-patches.rst - An emergency fix for (some) problems with Sphinx 3.x - Some welcome automarkup improvements to automatically generate cross-references to struct definitions and other documents - The usual collection of translation updates, typo fixes, etc" * tag 'docs-5.10' of git://git.lwn.net/linux: (81 commits) gpiolib: Update indentation in driver.rst for code excerpts Documentation/admin-guide: tainted-kernels: Fix typo occured Documentation: better locations for sysfs-pci, sysfs-tagging docs: programming-languages: refresh blurb on clang support Documentation: kvm: fix a typo Documentation: Chinese translation of Documentation/arm64/amu.rst doc: zh_CN: index files in arm64 subdirectory mailmap: add entry for <mstarovoitov@marvell.com> doc: seq_file: clarify role of *pos in ->next() docs: trace: ring-buffer-design.rst: use the new SPDX tag Documentation: kernel-parameters: clarify "module." parameters Fix references to nommu-mmap.rst docs: rewrite admin-guide/sysctl/abi.rst docs: fb: Remove vesafb scrollback boot option docs: fb: Remove sstfb scrollback boot option docs: fb: Remove matroxfb scrollback boot option docs: fb: Remove framebuffer scrollback boot option docs: replace the old User Mode Linux HowTo with a new one Documentation/admin-guide: blockdev/ramdisk: remove use of "rdev" Documentation/admin-guide: README & svga: remove use of "rdev" ...
2020-09-28KVM: x86: Introduce MSR filteringAlexander Graf1-0/+108
It's not desireable to have all MSRs always handled by KVM kernel space. Some MSRs would be useful to handle in user space to either emulate behavior (like uCode updates) or differentiate whether they are valid based on the CPU model. To allow user space to specify which MSRs it wants to see handled by KVM, this patch introduces a new ioctl to push filter rules with bitmaps into KVM. Based on these bitmaps, KVM can then decide whether to reject MSR access. With the addition of KVM_CAP_X86_USER_SPACE_MSR it can also deflect the denied MSR events to user space to operate on. If no filter is populated, MSR handling stays identical to before. Signed-off-by: Alexander Graf <graf@amazon.com> Message-Id: <20200925143422.21718-8-graf@amazon.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-28KVM: x86: Allow deflecting unknown MSR accesses to user spaceAlexander Graf1-8/+77
MSRs are weird. Some of them are normal control registers, such as EFER. Some however are registers that really are model specific, not very interesting to virtualization workloads, and not performance critical. Others again are really just windows into package configuration. Out of these MSRs, only the first category is necessary to implement in kernel space. Rarely accessed MSRs, MSRs that should be fine tunes against certain CPU models and MSRs that contain information on the package level are much better suited for user space to process. However, over time we have accumulated a lot of MSRs that are not the first category, but still handled by in-kernel KVM code. This patch adds a generic interface to handle WRMSR and RDMSR from user space. With this, any future MSR that is part of the latter categories can be handled in user space. Furthermore, it allows us to replace the existing "ignore_msrs" logic with something that applies per-VM rather than on the full system. That way you can run productive VMs in parallel to experimental ones where you don't care about proper MSR handling. Signed-off-by: Alexander Graf <graf@amazon.com> Reviewed-by: Jim Mattson <jmattson@google.com> Message-Id: <20200925143422.21718-3-graf@amazon.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-28KVM: x86: hyper-v: Mention SynDBG CPUID leaves in api.rstVitaly Kuznetsov1-1/+4
We forgot to update KVM_GET_SUPPORTED_HV_CPUID's documentation in api.rst when SynDBG leaves were added. While on it, fix 'KVM_GET_SUPPORTED_CPUID' copy-paste error. Fixes: f97f5a56f597 ("x86/kvm/hyper-v: Add support for synthetic debugger interface") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20200924145757.1035782-2-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-14docs: kvm: add documentation for KVM_CAP_S390_DIAG318Collin Walling1-0/+20
Documentation for the s390 DIAGNOSE 0x318 instruction handling. Signed-off-by: Collin Walling <walling@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/kvm/20200625150724.10021-2-walling@linux.ibm.com/ Message-Id: <20200625150724.10021-2-walling@linux.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-09-10docs: kvm: api.rst: add missing spacesMauro Carvalho Chehab1-1/+1
There are some warnings: Documentation/virt/kvm/api.rst:4354: WARNING: Definition list ends without a blank line; unexpected unindent. Documentation/virt/kvm/api.rst:4358: WARNING: Definition list ends without a blank line; unexpected unindent. Documentation/virt/kvm/api.rst:4363: WARNING: Definition list ends without a blank line; unexpected unindent. Produced by the lack of identation on a single line. That caused the literal block to end prematurely. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/b6b3679b6c2329dc9b16d397c289b5ade0184c63.1599660067.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-09docs: kvm: fix referenced ioctl symbolConnor Kuehl1-1/+1
The actual symbol that is exported and usable is 'KVM_MEMORY_ENCRYPT_OP', not 'KVM_MEM_ENCRYPT_OP' $ git grep -l KVM_MEM_ENCRYPT_OP Documentation/virt/kvm/amd-memory-encryption.rst $ git grep -l KVM_MEMORY_ENCRYPT_OP Documentation/virt/kvm/api.rst arch/x86/kvm/x86.c include/uapi/linux/kvm.h tools/include/uapi/linux/kvm.h While we're in there, update the KVM API category for KVM_MEMORY_ENCRYPT_OP. It is called on a VM file descriptor. Signed-off-by: Connor Kuehl <ckuehl@redhat.com> Link: https://lore.kernel.org/r/20200819211952.251984-1-ckuehl@redhat.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-08-21arm64/x86: KVM: Introduce steal-time capAndrew Jones1-0/+13
arm64 requires a vcpu fd (KVM_HAS_DEVICE_ATTR vcpu ioctl) to probe support for steal-time. However this is unnecessary, as only a KVM fd is required, and it complicates userspace (userspace may prefer delaying vcpu creation until after feature probing). Introduce a cap that can be checked instead. While x86 can already probe steal-time support with a kvm fd (KVM_GET_SUPPORTED_CPUID), we add the cap there too for consistency. Signed-off-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Steven Price <steven.price@arm.com> Link: https://lore.kernel.org/r/20200804170604.42662-7-drjones@redhat.com
2020-08-21KVM: Documentation: Minor fixupsAndrew Jones1-4/+5
In preparation for documenting a new capability let's fix up the formatting of the current ones. Signed-off-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Steven Price <steven.price@arm.com> Link: https://lore.kernel.org/r/20200804170604.42662-6-drjones@redhat.com
2020-08-07Merge tag 'powerpc-5.9-1' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Add support for (optionally) using queued spinlocks & rwlocks. - Support for a new faster system call ABI using the scv instruction on Power9 or later. - Drop support for the PROT_SAO mmap/mprotect flag as it will be unsupported on Power10 and future processors, leaving us with no way to implement the functionality it requests. This risks breaking userspace, though we believe it is unused in practice. - A bug fix for, and then the removal of, our custom stack expansion checking. We now allow stack expansion up to the rlimit, like other architectures. - Remove the remnants of our (previously disabled) topology update code, which tried to react to NUMA layout changes on virtualised systems, but was prone to crashes and other problems. - Add PMU support for Power10 CPUs. - A change to our signal trampoline so that we don't unbalance the link stack (branch return predictor) in the signal delivery path. - Lots of other cleanups, refactorings, smaller features and so on as usual. Thanks to: Abhishek Goel, Alastair D'Silva, Alexander A. Klimov, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Balamuruhan S, Bharata B Rao, Bill Wendling, Bin Meng, Cédric Le Goater, Chris Packham, Christophe Leroy, Christoph Hellwig, Daniel Axtens, Dan Williams, David Lamparter, Desnes A. Nunes do Rosario, Erhard F., Finn Thain, Frederic Barrat, Ganesh Goudar, Gautham R. Shenoy, Geoff Levand, Greg Kurz, Gustavo A. R. Silva, Hari Bathini, Harish, Imre Kaloz, Joel Stanley, Joe Perches, John Crispin, Jordan Niethe, Kajol Jain, Kamalesh Babulal, Kees Cook, Laurent Dufour, Leonardo Bras, Li RongQing, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Cave-Ayland, Michal Suchanek, Milton Miller, Mimi Zohar, Murilo Opsfelder Araujo, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nayna Jain, Nicholas Piggin, Oliver O'Halloran, Palmer Dabbelt, Pedro Miraglia Franco de Carvalho, Philippe Bergheaud, Pingfan Liu, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Randy Dunlap, Ravi Bangoria, Sachin Sant, Sam Bobroff, Sandipan Das, Santosh Sivaraj, Satheesh Rajendran, Shirisha Ganta, Sourabh Jain, Srikar Dronamraju, Stan Johnson, Stephen Rothwell, Thadeu Lima de Souza Cascardo, Thiago Jung Bauermann, Tom Lane, Vaibhav Jain, Vladis Dronov, Wei Yongjun, Wen Xiong, YueHaibing. * tag 'powerpc-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (337 commits) selftests/powerpc: Fix pkey syscall redefinitions powerpc: Fix circular dependency between percpu.h and mmu.h powerpc/powernv/sriov: Fix use of uninitialised variable selftests/powerpc: Skip vmx/vsx/tar/etc tests on older CPUs powerpc/40x: Fix assembler warning about r0 powerpc/papr_scm: Add support for fetching nvdimm 'fuel-gauge' metric powerpc/papr_scm: Fetch nvdimm performance stats from PHYP cpuidle: pseries: Fixup exit latency for CEDE(0) cpuidle: pseries: Add function to parse extended CEDE records cpuidle: pseries: Set the latency-hint before entering CEDE selftests/powerpc: Fix online CPU selection powerpc/perf: Consolidate perf_callchain_user_[64|32]() powerpc/pseries/hotplug-cpu: Remove double free in error path powerpc/pseries/mobility: Add pr_debug() for device tree changes powerpc/pseries/mobility: Set pr_fmt() powerpc/cacheinfo: Warn if cache object chain becomes unordered powerpc/cacheinfo: Improve diagnostics about malformed cache lists powerpc/cacheinfo: Use name@unit instead of full DT path in debug messages powerpc/cacheinfo: Set pr_fmt() powerpc: fix function annotations to avoid section mismatch warnings with gcc-10 ...
2020-08-06Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-0/+5
Pull KVM updates from Paolo Bonzini: "s390: - implement diag318 x86: - Report last CPU for debugging - Emulate smaller MAXPHYADDR in the guest than in the host - .noinstr and tracing fixes from Thomas - nested SVM page table switching optimization and fixes Generic: - Unify shadow MMU cache data structures across architectures" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (127 commits) KVM: SVM: Fix sev_pin_memory() error handling KVM: LAPIC: Set the TDCR settable bits KVM: x86: Specify max TDP level via kvm_configure_mmu() KVM: x86/mmu: Rename max_page_level to max_huge_page_level KVM: x86: Dynamically calculate TDP level from max level and MAXPHYADDR KVM: VXM: Remove temporary WARN on expected vs. actual EPTP level mismatch KVM: x86: Pull the PGD's level from the MMU instead of recalculating it KVM: VMX: Make vmx_load_mmu_pgd() static KVM: x86/mmu: Add separate helper for shadow NPT root page role calc KVM: VMX: Drop a duplicate declaration of construct_eptp() KVM: nSVM: Correctly set the shadow NPT root level in its MMU role KVM: Using macros instead of magic values MIPS: KVM: Fix build error caused by 'kvm_run' cleanup KVM: nSVM: remove nonsensical EXITINFO1 adjustment on nested NPF KVM: x86: Add a capability for GUEST_MAXPHYADDR < HOST_MAXPHYADDR support KVM: VMX: optimize #PF injection when MAXPHYADDR does not match KVM: VMX: Add guest physical address check in EPT violation and misconfig KVM: VMX: introduce vmx_need_pf_intercept KVM: x86: update exception bitmap on CPUID changes KVM: x86: rename update_bp_intercept to update_exception_bitmap ...
2020-08-05Merge tag 'docs-5.9' of git://git.lwn.net/linuxLinus Torvalds1-9/+9
Pull documentation updates from Jonathan Corbet: "It's been a busy cycle for documentation - hopefully the busiest for a while to come. Changes include: - Some new Chinese translations - Progress on the battle against double words words and non-HTTPS URLs - Some block-mq documentation - More RST conversions from Mauro. At this point, that task is essentially complete, so we shouldn't see this kind of churn again for a while. Unless we decide to switch to asciidoc or something...:) - Lots of typo fixes, warning fixes, and more" * tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits) scripts/kernel-doc: optionally treat warnings as errors docs: ia64: correct typo mailmap: add entry for <alobakin@marvell.com> doc/zh_CN: add cpu-load Chinese version Documentation/admin-guide: tainted-kernels: fix spelling mistake MAINTAINERS: adjust kprobes.rst entry to new location devices.txt: document rfkill allocation PCI: correct flag name docs: filesystems: vfs: correct flag name docs: filesystems: vfs: correct sync_mode flag names docs: path-lookup: markup fixes for emphasis docs: path-lookup: more markup fixes docs: path-lookup: fix HTML entity mojibake CREDITS: Replace HTTP links with HTTPS ones docs: process: Add an example for creating a fixes tag doc/zh_CN: add Chinese translation prefer section doc/zh_CN: add clearing-warn-once Chinese version doc/zh_CN: add admin-guide index doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label futex: MAINTAINERS: Re-add selftests directory ...
2020-07-22KVM: PPC: Book3S HV: Save/restore new PMU registersAthira Rajeev1-0/+3
Power ISA v3.1 has added new performance monitoring unit (PMU) special purpose registers (SPRs). They are: Monitor Mode Control Register 3 (MMCR3) Sampled Instruction Event Register A (SIER2) Sampled Instruction Event Register B (SIER3) Add support to save/restore these new SPRs while entering/exiting guest. Also include changes to support KVM_REG_PPC_MMCR3/SIER2/SIER3. Add new SPRs to KVM API documentation. Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1594996707-3727-6-git-send-email-atrajeev@linux.vnet.ibm.com
2020-07-13Documentation: virt/kvm/api: eliminate duplicated wordRandy Dunlap1-1/+1
Drop the duplicated word "struct". Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: kvm@vger.kernel.org Link: https://lore.kernel.org/r/20200707180414.10467-21-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-07-10KVM: nVMX: fixes for preemption timer migrationPaolo Bonzini1-2/+3
Commit 850448f35aaf ("KVM: nVMX: Fix VMX preemption timer migration", 2020-06-01) accidentally broke nVMX live migration from older version by changing the userspace ABI. Restore it and, while at it, ensure that vmx->nested.has_preemption_timer_deadline is always initialized according to the KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE flag. Cc: Makarand Sonare <makarandsonare@google.com> Fixes: 850448f35aaf ("KVM: nVMX: Fix VMX preemption timer migration") Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-08KVM: X86: Reset vcpu->arch.cpuid_nent to 0 if SET_CPUID* failsXiaoyao Li1-0/+4
Current implementation keeps userspace input of CPUID configuration and cpuid->nent even if kvm_update_cpuid() fails. Reset vcpu->arch.cpuid_nent to 0 for the case of failure as a simple fix. Besides, update the doc to explicitly state that if IOCTL SET_CPUID* fail KVM gives no gurantee that previous valid CPUID configuration is kept. Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Message-Id: <20200708065054.19713-2-xiaoyao.li@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-08kvm: x86: Add "last CPU" to some KVM_EXIT informationJim Mattson1-0/+1
More often than not, a failed VM-entry in an x86 production environment is induced by a defective CPU. To help identify the bad hardware, include the id of the last logical CPU to run a vCPU in the information provided to userspace on a KVM exit for failed VM-entry or for KVM internal errors not associated with emulation. The presence of this additional information is indicated by a new capability, KVM_CAP_LAST_CPU. Signed-off-by: Jim Mattson <jmattson@google.com> Reviewed-by: Oliver Upton <oupton@google.com> Reviewed-by: Peter Shier <pshier@google.com> Message-Id: <20200603235623.245638-5-jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-05Documentation: virt: kvm/api: drop doubled wordsRandy Dunlap1-8/+8
Drop multiple doubled words. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: kvm@vger.kernel.org Link: https://lore.kernel.org/r/20200703212906.30655-3-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-06-04Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-1/+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 ...
2020-06-01Merge tag 'kvmarm-5.8' of ↵Paolo Bonzini1-1/+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
2020-06-01x86/kvm/hyper-v: Add support for synthetic debugger interfaceJon Doron1-0/+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>
2020-06-01KVM: nVMX: Fix VMX preemption timer migrationPeter Shier1-0/+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>
2020-06-01x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exitJon Doron1-0/+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>
2020-05-16KVM: arm64: Support enabling dirty log gradually in small chunksKeqian Zhu1-1/+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
2020-05-05docs: kvm: Fix KVM_KVMCLOCK_CTRL API docJoshua Abraham1-5/+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>
2020-04-24kvm: add capability for halt pollingDavid Matlack1-0/+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>
2020-03-31Merge tag 'kvm-ppc-next-5.7-1' of ↵Paolo Bonzini1-0/+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.
2020-03-30Merge tag 'kvm-s390-next-5.7-3' of ↵Paolo Bonzini1-0/+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
2020-03-27s390/gmap: return proper error code on ksm unsharingChristian Borntraeger1-0/+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>
2020-03-26KVM: PPC: Book3S HV: Add a capability for enabling secure guestsPaul Mackerras1-0/+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>
2020-03-16Merge tag 'kvm-s390-next-5.7-1' of ↵Paolo Bonzini1-2/+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)
2020-03-16KVM: x86: Remove stateful CPUID handlingSean Christopherson1-18/+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>
2020-03-16KVM: x86: enable dirty log gradually in small chunksJay Zhou1-3/+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>
2020-02-27KVM: s390: protvirt: Add KVM api documentationJanosch Frank1-0/+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>
2020-02-27KVM: s390: protvirt: disallow one_regJanosch Frank1-2/+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>
2020-02-24KVM: s390: rstify new ioctls in api.rstChristian Borntraeger1-15/+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>
2020-02-12docs: kvm: Convert api.txt to ReST formatMauro Carvalho Chehab1-0/+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>