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* Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2022-05-261-16/+236
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kvm updates from Paolo Bonzini: "S390: - ultravisor communication device driver - fix TEID on terminating storage key ops RISC-V: - Added Sv57x4 support for G-stage page table - Added range based local HFENCE functions - Added remote HFENCE functions based on VCPU requests - Added ISA extension registers in ONE_REG interface - Updated KVM RISC-V maintainers entry to cover selftests support ARM: - Add support for the ARMv8.6 WFxT extension - Guard pages for the EL2 stacks - Trap and emulate AArch32 ID registers to hide unsupported features - Ability to select and save/restore the set of hypercalls exposed to the guest - Support for PSCI-initiated suspend in collaboration with userspace - GICv3 register-based LPI invalidation support - Move host PMU event merging into the vcpu data structure - GICv3 ITS save/restore fixes - The usual set of small-scale cleanups and fixes x86: - New ioctls to get/set TSC frequency for a whole VM - Allow userspace to opt out of hypercall patching - Only do MSR filtering for MSRs accessed by rdmsr/wrmsr AMD SEV improvements: - Add KVM_EXIT_SHUTDOWN metadata for SEV-ES - V_TSC_AUX support Nested virtualization improvements for AMD: - Support for "nested nested" optimizations (nested vVMLOAD/VMSAVE, nested vGIF) - Allow AVIC to co-exist with a nested guest running - Fixes for LBR virtualizations when a nested guest is running, and nested LBR virtualization support - PAUSE filtering for nested hypervisors Guest support: - Decoupling of vcpu_is_preempted from PV spinlocks" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (199 commits) KVM: x86: Fix the intel_pt PMI handling wrongly considered from guest KVM: selftests: x86: Sync the new name of the test case to .gitignore Documentation: kvm: reorder ARM-specific section about KVM_SYSTEM_EVENT_SUSPEND x86, kvm: use correct GFP flags for preemption disabled KVM: LAPIC: Drop pending LAPIC timer injection when canceling the timer x86/kvm: Alloc dummy async #PF token outside of raw spinlock KVM: x86: avoid calling x86 emulator without a decoded instruction KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak x86/fpu: KVM: Set the base guest FPU uABI size to sizeof(struct kvm_xsave) s390/uv_uapi: depend on CONFIG_S390 KVM: selftests: x86: Fix test failure on arch lbr capable platforms KVM: LAPIC: Trace LAPIC timer expiration on every vmentry KVM: s390: selftest: Test suppression indication on key prot exception KVM: s390: Don't indicate suppression on dirtying, failing memop selftests: drivers/s390x: Add uvdevice tests drivers/s390/char: Add Ultravisor io device MAINTAINERS: Update KVM RISC-V entry to cover selftests support RISC-V: KVM: Introduce ISA extension register RISC-V: KVM: Cleanup stale TLB entries when host CPU changes RISC-V: KVM: Add remote HFENCE functions based on VCPU requests ...
| * Documentation: kvm: reorder ARM-specific section about KVM_SYSTEM_EVENT_SUSPENDPaolo Bonzini2022-05-251-26/+26
| | | | | | | | Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * Merge tag 'kvm-s390-next-5.19-1' of ↵Paolo Bonzini2022-05-251-0/+6
| |\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD KVM: s390: Fix and feature for 5.19 - ultravisor communication device driver - fix TEID on terminating storage key ops
| | * KVM: s390: Don't indicate suppression on dirtying, failing memopJanis Schoetterl-Glausch2022-05-201-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If user space uses a memop to emulate an instruction and that memop fails, the execution of the instruction ends. Instruction execution can end in different ways, one of which is suppression, which requires that the instruction execute like a no-op. A writing memop that spans multiple pages and fails due to key protection may have modified guest memory, as a result, the likely correct ending is termination. Therefore, do not indicate a suppressing instruction ending in this case. Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Link: https://lore.kernel.org/r/20220512131019.2594948-2-scgl@linux.ibm.com Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
| * | Merge tag 'kvmarm-5.19' of ↵Paolo Bonzini2022-05-251-3/+93
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for 5.19 - Add support for the ARMv8.6 WFxT extension - Guard pages for the EL2 stacks - Trap and emulate AArch32 ID registers to hide unsupported features - Ability to select and save/restore the set of hypercalls exposed to the guest - Support for PSCI-initiated suspend in collaboration with userspace - GICv3 register-based LPI invalidation support - Move host PMU event merging into the vcpu data structure - GICv3 ITS save/restore fixes - The usual set of small-scale cleanups and fixes [Due to the conflict, KVM_SYSTEM_EVENT_SEV_TERM is relocated from 4 to 6. - Paolo]
| | * \ Merge branch kvm-arm64/psci-suspend into kvmarm-master/nextMarc Zyngier2022-05-161-2/+74
| | |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * kvm-arm64/psci-suspend: : . : Add support for PSCI SYSTEM_SUSPEND and allow userspace to : filter the wake-up events. : : Patches courtesy of Oliver. : . Documentation: KVM: Fix title level for PSCI_SUSPEND selftests: KVM: Test SYSTEM_SUSPEND PSCI call selftests: KVM: Refactor psci_test to make it amenable to new tests selftests: KVM: Use KVM_SET_MP_STATE to power off vCPU in psci_test selftests: KVM: Create helper for making SMCCC calls selftests: KVM: Rename psci_cpu_on_test to psci_test KVM: arm64: Implement PSCI SYSTEM_SUSPEND KVM: arm64: Add support for userspace to suspend a vCPU KVM: arm64: Return a value from check_vcpu_requests() KVM: arm64: Rename the KVM_REQ_SLEEP handler KVM: arm64: Track vCPU power state using MP state values KVM: arm64: Dedupe vCPU power off helpers KVM: arm64: Don't depend on fallthrough to hide SYSTEM_RESET2 Signed-off-by: Marc Zyngier <maz@kernel.org>
| | | * | Documentation: KVM: Fix title level for PSCI_SUSPENDStephen Rothwell2022-05-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The htmldoc build breaks in a funny way with: <quote> Sphinx parallel build error: docutils.utils.SystemMessage: /home/sfr/next/next/Documentation/virt/kvm/api.rst:6175: (SEVERE/4) Title level inconsistent: For arm/arm64: ^^^^^^^^^^^^^^ </quote> Swap the ^^s for a bunch of --s... Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> [maz: commit message] Signed-off-by: Marc Zyngier <maz@kernel.org>
| | | * | KVM: arm64: Implement PSCI SYSTEM_SUSPENDOliver Upton2022-05-041-0/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ARM DEN0022D.b 5.19 "SYSTEM_SUSPEND" describes a PSCI call that allows software to request that a system be placed in the deepest possible low-power state. Effectively, software can use this to suspend itself to RAM. Unfortunately, there really is no good way to implement a system-wide PSCI call in KVM. Any precondition checks done in the kernel will need to be repeated by userspace since there is no good way to protect a critical section that spans an exit to userspace. SYSTEM_RESET and SYSTEM_OFF are equally plagued by this issue, although no users have seemingly cared for the relatively long time these calls have been supported. The solution is to just make the whole implementation userspace's problem. Introduce a new system event, KVM_SYSTEM_EVENT_SUSPEND, that indicates to userspace a calling vCPU has invoked PSCI SYSTEM_SUSPEND. Additionally, add a CAP to get buy-in from userspace for this new exit type. Only advertise the SYSTEM_SUSPEND PSCI call if userspace has opted in. If a vCPU calls SYSTEM_SUSPEND, punt straight to userspace. Provide explicit documentation of userspace's responsibilites for the exit and point to the PSCI specification to describe the actual PSCI call. Reviewed-by: Reiji Watanabe <reijiw@google.com> Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220504032446.4133305-8-oupton@google.com
| | | * | KVM: arm64: Add support for userspace to suspend a vCPUOliver Upton2022-05-041-2/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce a new MP state, KVM_MP_STATE_SUSPENDED, which indicates a vCPU is in a suspended state. In the suspended state the vCPU will block until a wakeup event (pending interrupt) is recognized. Add a new system event type, KVM_SYSTEM_EVENT_WAKEUP, to indicate to userspace that KVM has recognized one such wakeup event. It is the responsibility of userspace to then make the vCPU runnable, or leave it suspended until the next wakeup event. Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220504032446.4133305-7-oupton@google.com
| | * | | Merge branch kvm-arm64/hcall-selection into kvmarm-master/nextMarc Zyngier2022-05-161-0/+18
| | |\ \ \ | | | |/ / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * kvm-arm64/hcall-selection: : . : Introduce a new set of virtual sysregs for userspace to : select the hypercalls it wants to see exposed to the guest. : : Patches courtesy of Raghavendra and Oliver. : . KVM: arm64: Fix hypercall bitmap writeback when vcpus have already run KVM: arm64: Hide KVM_REG_ARM_*_BMAP_BIT_COUNT from userspace Documentation: Fix index.rst after psci.rst renaming selftests: KVM: aarch64: Add the bitmap firmware registers to get-reg-list selftests: KVM: aarch64: Introduce hypercall ABI test selftests: KVM: Create helper for making SMCCC calls selftests: KVM: Rename psci_cpu_on_test to psci_test tools: Import ARM SMCCC definitions Docs: KVM: Add doc for the bitmap firmware registers Docs: KVM: Rename psci.rst to hypercalls.rst KVM: arm64: Add vendor hypervisor firmware register KVM: arm64: Add standard hypervisor firmware register KVM: arm64: Setup a framework for hypercall bitmap firmware registers KVM: arm64: Factor out firmware register handling from psci.c Signed-off-by: Marc Zyngier <maz@kernel.org>
| | | * | Docs: KVM: Add doc for the bitmap firmware registersRaghavendra Rao Ananta2022-05-031-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the documentation for the bitmap firmware registers in hypercalls.rst and api.rst. This includes the details for KVM_REG_ARM_STD_BMAP, KVM_REG_ARM_STD_HYP_BMAP, and KVM_REG_ARM_VENDOR_HYP_BMAP registers. Since the document is growing to carry other hypercall related information, make necessary adjustments to present the document in a generic sense, rather than being PSCI focused. Signed-off-by: Raghavendra Rao Ananta <rananta@google.com> Reviewed-by: Gavin Shan <gshan@redhat.com> [maz: small scale reformat, move things about, random typo fixes] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220502233853.1233742-7-rananta@google.com
| * | | | Merge branch 'kvm-fixes-for-5.18-rc5' into HEADPaolo Bonzini2022-04-291-12/+15
| |\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fixes for (relatively) old bugs, to be merged in both the -rc and next development trees. The merge reconciles the ABI fixes for KVM_EXIT_SYSTEM_EVENT between 5.18 and commit c24a950ec7d6 ("KVM, SEV: Add KVM_EXIT_SHUTDOWN metadata for SEV-ES", 2022-04-13).
| * | | | KVM, SEV: Add KVM_EXIT_SHUTDOWN metadata for SEV-ESPeter Gonda2022-04-131-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If an SEV-ES guest requests termination, exit to userspace with KVM_EXIT_SYSTEM_EVENT and a dedicated SEV_TERM type instead of -EINVAL so that userspace can take appropriate action. See AMD's GHCB spec section '4.1.13 Termination Request' for more details. Suggested-by: Sean Christopherson <seanjc@google.com> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Peter Gonda <pgonda@google.com> Reported-by: kernel test robot <lkp@intel.com> Message-Id: <20220407210233.782250-1-pgonda@google.com> [Add documentatino. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | Merge branch 'kvm-older-features' into HEADPaolo Bonzini2022-04-131-14/+135
| |\ \ \ \ | | |_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge branch for features that did not make it into 5.18: * New ioctls to get/set TSC frequency for a whole VM * Allow userspace to opt out of hypercall patching Nested virtualization improvements for AMD: * Support for "nested nested" optimizations (nested vVMLOAD/VMSAVE, nested vGIF) * Allow AVIC to co-exist with a nested guest running * Fixes for LBR virtualizations when a nested guest is running, and nested LBR virtualization support * PAUSE filtering for nested hypervisors Guest support: * Decoupling of vcpu_is_preempted from PV spinlocks Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | KVM: x86: Accept KVM_[GS]ET_TSC_KHZ as a VM ioctl.David Woodhouse2022-04-021-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This sets the default TSC frequency for subsequently created vCPUs. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20220225145304.36166-2-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | KVM: x86/xen: Advertise and document KVM_XEN_HVM_CONFIG_EVTCHN_SENDDavid Woodhouse2022-04-021-10/+119
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At the end of the patch series adding this batch of event channel acceleration features, finally add the feature bit which advertises them and document it all. For SCHEDOP_poll we need to wake a polling vCPU when a given port is triggered, even when it's masked — and we want to implement that in the kernel, for efficiency. So we want the kernel to know that it has sole ownership of event channel delivery. Thus, we allow userspace to make the 'promise' by setting the corresponding feature bit in its KVM_XEN_HVM_CONFIG call. As we implement SCHEDOP_poll bypass later, we will do so only if that promise has been made by userspace. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20220303154127.202856-16-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | KVM: x86: Allow userspace to opt out of hypercall patchingOliver Upton2022-04-021-0/+9
| | | |/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KVM handles the VMCALL/VMMCALL instructions very strangely. Even though both of these instructions really should #UD when executed on the wrong vendor's hardware (i.e. VMCALL on SVM, VMMCALL on VMX), KVM replaces the guest's instruction with the appropriate instruction for the vendor. Nonetheless, older guest kernels without commit c1118b3602c2 ("x86: kvm: use alternatives for VMCALL vs. VMMCALL if kernel text is read-only") do not patch in the appropriate instruction using alternatives, likely motivating KVM's intervention. Add a quirk allowing userspace to opt out of hypercall patching. If the quirk is disabled, KVM synthesizes a #UD in the guest. Signed-off-by: Oliver Upton <oupton@google.com> Message-Id: <20220316005538.2282772-2-oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | | | Merge tag 'arm64-upstream' of ↵Linus Torvalds2022-05-231-0/+2
|\ \ \ \ | |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - Initial support for the ARMv9 Scalable Matrix Extension (SME). SME takes the approach used for vectors in SVE and extends this to provide architectural support for matrix operations. No KVM support yet, SME is disabled in guests. - Support for crashkernel reservations above ZONE_DMA via the 'crashkernel=X,high' command line option. - btrfs search_ioctl() fix for live-lock with sub-page faults. - arm64 perf updates: support for the Hisilicon "CPA" PMU for monitoring coherent I/O traffic, support for Arm's CMN-650 and CMN-700 interconnect PMUs, minor driver fixes, kerneldoc cleanup. - Kselftest updates for SME, BTI, MTE. - Automatic generation of the system register macros from a 'sysreg' file describing the register bitfields. - Update the type of the function argument holding the ESR_ELx register value to unsigned long to match the architecture register size (originally 32-bit but extended since ARMv8.0). - stacktrace cleanups. - ftrace cleanups. - Miscellaneous updates, most notably: arm64-specific huge_ptep_get(), avoid executable mappings in kexec/hibernate code, drop TLB flushing from get_clear_flush() (and rename it to get_clear_contig()), ARCH_NR_GPIO bumped to 2048 for ARCH_APPLE. * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (145 commits) arm64/sysreg: Generate definitions for FAR_ELx arm64/sysreg: Generate definitions for DACR32_EL2 arm64/sysreg: Generate definitions for CSSELR_EL1 arm64/sysreg: Generate definitions for CPACR_ELx arm64/sysreg: Generate definitions for CONTEXTIDR_ELx arm64/sysreg: Generate definitions for CLIDR_EL1 arm64/sve: Move sve_free() into SVE code section arm64: Kconfig.platforms: Add comments arm64: Kconfig: Fix indentation and add comments arm64: mm: avoid writable executable mappings in kexec/hibernate code arm64: lds: move special code sections out of kernel exec segment arm64/hugetlb: Implement arm64 specific huge_ptep_get() arm64/hugetlb: Use ptep_get() to get the pte value of a huge page arm64: kdump: Do not allocate crash low memory if not needed arm64/sve: Generate ZCR definitions arm64/sme: Generate defintions for SVCR arm64/sme: Generate SMPRI_EL1 definitions arm64/sme: Automatically generate SMPRIMAP_EL2 definitions arm64/sme: Automatically generate SMIDR_EL1 defines arm64/sme: Automatically generate defines for SMCR ...
| * | | KVM: arm64: uapi: Add kvm_debug_exit_arch.hsr_highAlexandru Elisei2022-04-291-0/+2
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When userspace is debugging a VM, the kvm_debug_exit_arch part of the kvm_run struct contains arm64 specific debug information: the ESR_EL2 value, encoded in the field "hsr", and the address of the instruction that caused the exception, encoded in the field "far". Linux has moved to treating ESR_EL2 as a 64-bit register, but unfortunately kvm_debug_exit_arch.hsr cannot be changed because that would change the memory layout of the struct on big endian machines: Current layout: | Layout with "hsr" extended to 64 bits: | offset 0: ESR_EL2[31:0] (hsr) | offset 0: ESR_EL2[61:32] (hsr[61:32]) offset 4: padding | offset 4: ESR_EL2[31:0] (hsr[31:0]) offset 8: FAR_EL2[61:0] (far) | offset 8: FAR_EL2[61:0] (far) which breaks existing code. The padding is inserted by the compiler because the "far" field must be aligned to 8 bytes (each field must be naturally aligned - aapcs64 [1], page 18), and the struct itself must be aligned to 8 bytes (the struct must be aligned to the maximum alignment of its fields - aapcs64, page 18), which means that "hsr" must be aligned to 8 bytes as it is the first field in the struct. To avoid changing the struct size and layout for the existing fields, add a new field, "hsr_high", which replaces the existing padding. "hsr_high" will be used to hold the ESR_EL2[61:32] bits of the register. The memory layout, both on big and little endian machine, becomes: offset 0: ESR_EL2[31:0] (hsr) offset 4: ESR_EL2[61:32] (hsr_high) offset 8: FAR_EL2[61:0] (far) The padding that the compiler inserts for the current struct layout is unitialized. To prevent an updated userspace running on an old kernel mistaking the padding for a valid "hsr_high" value, add a new flag, KVM_DEBUG_ARCH_HSR_HIGH_VALID, to kvm_run->flags to let userspace know that "hsr_high" holds a valid ESR_EL2[61:32] value. [1] https://github.com/ARM-software/abi-aa/releases/download/2021Q3/aapcs64.pdf Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220425114444.368693-6-alexandru.elisei@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* / / KVM: fix bad user ABI for KVM_EXIT_SYSTEM_EVENTPaolo Bonzini2022-04-291-7/+17
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When KVM_EXIT_SYSTEM_EVENT was introduced, it included a flags member that at the time was unused. Unfortunately this extensibility mechanism has several issues: - x86 is not writing the member, so it would not be possible to use it on x86 except for new events - the member is not aligned to 64 bits, so the definition of the uAPI struct is incorrect for 32- on 64-bit userspace. This is a problem for RISC-V, which supports CONFIG_KVM_COMPAT, but fortunately usage of flags was only introduced in 5.18. Since padding has to be introduced, place a new field in there that tells if the flags field is valid. To allow further extensibility, in fact, change flags to an array of 16 values, and store how many of the values are valid. The availability of the new ndata field is tied to a system capability; all architectures are changed to fill in the field. To avoid breaking compilation of userspace that was using the flags field, provide a userspace-only union to overlap flags with data[0]. The new field is placed at the same offset for both 32- and 64-bit userspace. Cc: Will Deacon <will@kernel.org> Cc: Marc Zyngier <maz@kernel.org> Cc: Peter Gonda <pgonda@google.com> Cc: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reported-by: kernel test robot <lkp@intel.com> Message-Id: <20220422103013.34832-1-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* / Documentation: kvm: Add missing line break in api.rstBagas Sanjaya2022-04-051-0/+1
|/ | | | | | | | | | | | | | | | | | | | | | Add missing line break separator between literal block and description of KVM_EXIT_RISCV_SBI. This fixes: </path/to/linux>/Documentation/virt/kvm/api.rst:6118: WARNING: Literal block ends without a blank line; unexpected unindent. Fixes: da40d85805937d (RISC-V: KVM: Document RISC-V specific parts of KVM API, 2021-09-27) Cc: Anup Patel <anup.patel@wdc.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-riscv@lists.infradead.org Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Message-Id: <20220403065735.23859-1-bagasdotme@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: MIPS: remove reference to trap&emulate virtualizationPaolo Bonzini2022-04-021-6/+0
| | | | | | Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20220313140522.1307751-1-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: document limitations of MSR filteringPaolo Bonzini2022-04-021-0/+5
| | | | | | | | MSR filtering requires an exit to userspace that is hard to implement and would be very slow in the case of nested VMX vmexit and vmentry MSR accesses. Document the limitation. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: Remove dirty handling from gfn_to_pfn_cache completelyDavid Woodhouse2022-04-021-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It isn't OK to cache the dirty status of a page in internal structures for an indefinite period of time. Any time a vCPU exits the run loop to userspace might be its last; the VMM might do its final check of the dirty log, flush the last remaining dirty pages to the destination and complete a live migration. If we have internal 'dirty' state which doesn't get flushed until the vCPU is finally destroyed on the source after migration is complete, then we have lost data because that will escape the final copy. This problem already exists with the use of kvm_vcpu_unmap() to mark pages dirty in e.g. VMX nesting. Note that the actual Linux MM already considers the page to be dirty since we have a writeable mapping of it. This is just about the KVM dirty logging. For the nesting-style use cases (KVM_GUEST_USES_PFN) we will need to track which gfn_to_pfn_caches have been used and explicitly mark the corresponding pages dirty before returning to userspace. But we would have needed external tracking of that anyway, rather than walking the full list of GPCs to find those belonging to this vCPU which are dirty. So let's rely *solely* on that external tracking, and keep it simple rather than laying a tempting trap for callers to fall into. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20220303154127.202856-3-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Documentation: KVM: add API issues sectionPaolo Bonzini2022-03-291-0/+46
| | | | | | | | | | | Add a section to document all the different ways in which the KVM API sucks. I am sure there are way more, give people a place to vent so that userspace authors are aware. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20220322110712.222449-4-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: Introduce KVM_CAP_DISABLE_QUIRKS2Oliver Upton2022-03-211-0/+50
| | | | | | | | | | | | | | | | | | | | KVM_CAP_DISABLE_QUIRKS is irrevocably broken. The capability does not advertise the set of quirks which may be disabled to userspace, so it is impossible to predict the behavior of KVM. Worse yet, KVM_CAP_DISABLE_QUIRKS will tolerate any value for cap->args[0], meaning it fails to reject attempts to set invalid quirk bits. The only valid workaround for the quirky quirks API is to add a new CAP. Actually advertise the set of quirks that can be disabled to userspace so it can predict KVM's behavior. Reject values for cap->args[0] that contain invalid bits. Finally, add documentation for the new capability and describe the existing quirks. Signed-off-by: Oliver Upton <oupton@google.com> Message-Id: <20220301060351.442881-5-oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Merge tag 'kvmarm-5.18' of ↵Paolo Bonzini2022-03-181-44/+48
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for 5.18 - Proper emulation of the OSLock feature of the debug architecture - Scalibility improvements for the MMU lock when dirty logging is on - New VMID allocator, which will eventually help with SVA in VMs - Better support for PMUs in heterogenous systems - PSCI 1.1 support, enabling support for SYSTEM_RESET2 - Implement CONFIG_DEBUG_LIST at EL2 - Make CONFIG_ARM64_ERRATUM_2077057 default y - Reduce the overhead of VM exit when no interrupt is pending - Remove traces of 32bit ARM host support from the documentation - Updated vgic selftests - Various cleanups, doc updates and spelling fixes
| * Merge branch kvm-arm64/misc-5.18 into kvmarm-master/nextMarc Zyngier2022-03-091-44/+43
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * kvm-arm64/misc-5.18: : . : Misc fixes for KVM/arm64 5.18: : : - Drop unused kvm parameter to kvm_psci_version() : : - Implement CONFIG_DEBUG_LIST at EL2 : : - Make CONFIG_ARM64_ERRATUM_2077057 default y : : - Only do the interrupt dance if we have exited because of an interrupt : : - Remove traces of 32bit ARM host support from the documentation : . Documentation: KVM: Update documentation to indicate KVM is arm64-only KVM: arm64: Only open the interrupt window on exit due to an interrupt KVM: arm64: Enable Cortex-A510 erratum 2077057 by default Signed-off-by: Marc Zyngier <maz@kernel.org>
| | * Documentation: KVM: Update documentation to indicate KVM is arm64-onlyOliver Upton2022-03-091-44/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KVM support for 32-bit ARM hosts (KVM/arm) has been removed from the kernel since commit 541ad0150ca4 ("arm: Remove 32bit KVM host support"). There still exists some remnants of the old architecture in the KVM documentation. Remove all traces of 32-bit host support from the documentation. Note that AArch32 guests are still supported. Suggested-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220308172856.2997250-1-oupton@google.com
| * | KVM: arm64: Indicate SYSTEM_RESET2 in kvm_run::system_event flags fieldWill Deacon2022-02-211-0/+5
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When handling reset and power-off PSCI calls from the guest, we initialise X0 to PSCI_RET_INTERNAL_FAILURE in case the VMM tries to re-run the vCPU after issuing the call. Unfortunately, this also means that the VMM cannot see which PSCI call was issued and therefore cannot distinguish between PSCI SYSTEM_RESET and SYSTEM_RESET2 calls, which is necessary in order to determine the validity of the "reset_type" in X1. Allocate bit 0 of the previously unused 'flags' field of the system_event structure so that we can indicate the PSCI call used to initiate the reset. Cc: Marc Zyngier <maz@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220221153524.15397-4-will@kernel.org
* | Merge branch 'kvm-bugfixes' into HEADPaolo Bonzini2022-03-041-1/+1
|\ \ | | | | | | | | | Merge bugfixes from 5.17 before merging more tricky work.
| * \ Merge branch 'kvm-ppc-cap-210' into kvm-masterPaolo Bonzini2022-02-221-0/+14
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | By request of Nick Piggin: > Patch 3 requires a KVM_CAP_PPC number allocated. QEMU maintainers are > happy with it (link in changelog) just waiting on KVM upstreaming. Do > you have objections to the series going to ppc/kvm tree first, or > another option is you could take patch 3 alone first (it's relatively > independent of the other 2) and ppc/kvm gets it from you?
| * | | KVM: x86: Add KVM_CAP_ENABLE_CAP to x86Aaron Lewis2022-02-171-1/+1
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <aaronlewis@google.com> Message-Id: <20220214212950.1776943-1-aaronlewis@google.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | | KVM: x86: Provide per VM capability for disabling PMU virtualizationDavid Dunn2022-02-251-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a new capability, KVM_CAP_PMU_CAPABILITY, that takes a bitmask of settings/features to allow userspace to configure PMU virtualization on a per-VM basis. For now, support a single flag, KVM_PMU_CAP_DISABLE, to allow disabling PMU virtualization for a VM even when KVM is configured with enable_pmu=true a module level. To keep KVM simple, disallow changing VM's PMU configuration after vCPUs have been created. Signed-off-by: David Dunn <daviddunn@google.com> Message-Id: <20220223225743.2703915-2-daviddunn@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | | Merge branch 'kvm-ppc-cap-210' into kvm-next-5.18Paolo Bonzini2022-02-241-0/+14
|\ \ \ | | |/ | |/|
| * | KVM: PPC: reserve capability 210 for KVM_CAP_PPC_AIL_MODE_3Nicholas Piggin2022-02-221-0/+14
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | Add KVM_CAP_PPC_AIL_MODE_3 to advertise the capability to set the AIL resource mode to 3 with the H_SET_MODE hypercall. This capability differs between processor types and KVM types (PR, HV, Nested HV), and affects guest-visible behaviour. QEMU will implement a cap-ail-mode-3 to control this behaviour[1], and use the KVM CAP if available to determine KVM support[2]. Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: s390: Clarify key argument for MEM_OP in api docsJanis Schoetterl-Glausch2022-02-221-1/+1
| | | | | | | | | | | | | | | | | | | | Clarify that the key argument represents the access key, not the whole storage key. Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> Link: https://lore.kernel.org/r/20220221143657.3712481-1-scgl@linux.ibm.com Fixes: 5e35d0eb472b ("KVM: s390: Update api documentation for memop ioctl") Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
* | KVM: s390: Update api documentation for memop ioctlJanis Schoetterl-Glausch2022-02-141-22/+90
|/ | | | | | | | | | | | Document all currently existing operations, flags and explain under which circumstances they are available. Document the recently introduced absolute operations and the storage key protection flag, as well as the existing SIDA operations. Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Link: https://lore.kernel.org/r/20220211182215.2730017-10-scgl@linux.ibm.com Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
* KVM: x86: add system attribute to retrieve full set of supported xsave statesPaolo Bonzini2022-01-281-1/+3
| | | | | | | | | | | | | | | | | | Because KVM_GET_SUPPORTED_CPUID is meant to be passed (by simple-minded VMMs) to KVM_SET_CPUID2, it cannot include any dynamic xsave states that have not been enabled. Probing those, for example so that they can be passed to ARCH_REQ_XCOMP_GUEST_PERM, requires a new ioctl or arch_prctl. The latter is in fact worse, even though that is what the rest of the API uses, because it would require supported_xcr0 to be moved from the KVM module to the kernel just for this use. In addition, the value would be nonsensical (or an error would have to be returned) until the KVM module is loaded in. Therefore, to limit the growth of system ioctls, add a /dev/kvm variant of KVM_{GET,HAS}_DEVICE_ATTR, and implement it in x86 with just one group (0) and attribute (KVM_X86_XCOMP_GUEST_SUPP). Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* docs: kvm: fix WARNINGs from api.rstWei Wang2022-01-201-3/+3
| | | | | | | | | | | | Use the api number 134 for KVM_GET_XSAVE2, instead of 42, which has been used by KVM_GET_XSAVE. Also, fix the WARNINGs of the underlines being too short. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Wei Wang <wei.w.wang@intel.com> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Message-Id: <20220120045003.315177-1-wei.w.wang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kvm: x86: Add support for getting/setting expanded xstate bufferGuang Zeng2022-01-141-2/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | With KVM_CAP_XSAVE, userspace uses a hardcoded 4KB buffer to get/set xstate data from/to KVM. This doesn't work when dynamic xfeatures (e.g. AMX) are exposed to the guest as they require a larger buffer size. Introduce a new capability (KVM_CAP_XSAVE2). Userspace VMM gets the required xstate buffer size via KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2). KVM_SET_XSAVE is extended to work with both legacy and new capabilities by doing properly-sized memdup_user() based on the guest fpu container. KVM_GET_XSAVE is kept for backward-compatible reason. Instead, KVM_GET_XSAVE2 is introduced under KVM_CAP_XSAVE2 as the preferred interface for getting xstate buffer (4KB or larger size) from KVM (Link: https://lkml.org/lkml/2021/12/15/510) Also, update the api doc with the new KVM_GET_XSAVE2 ioctl. Signed-off-by: Guang Zeng <guang.zeng@intel.com> Signed-off-by: Wei Wang <wei.w.wang@intel.com> Signed-off-by: Jing Liu <jing2.liu@intel.com> Signed-off-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Yang Zhong <yang.zhong@intel.com> Message-Id: <20220105123532.12586-19-yang.zhong@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kvm: x86: Exclude unpermitted xfeatures at KVM_GET_SUPPORTED_CPUIDJing Liu2022-01-071-0/+4
| | | | | | | | | | | | | | | | KVM_GET_SUPPORTED_CPUID should not include any dynamic xstates in CPUID[0xD] if they have not been requested with prctl. Otherwise a process which directly passes KVM_GET_SUPPORTED_CPUID to KVM_SET_CPUID2 would now fail even if it doesn't intend to use a dynamically enabled feature. Userspace must know that prctl is required and allocate >4K xstate buffer before setting any dynamic bit. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jing Liu <jing2.liu@intel.com> Signed-off-by: Yang Zhong <yang.zhong@intel.com> Message-Id: <20220105123532.12586-5-yang.zhong@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86/xen: Add KVM_IRQ_ROUTING_XEN_EVTCHN and event channel deliveryDavid Woodhouse2022-01-071-0/+21
| | | | | | | | | | | | | | | | | | | | This adds basic support for delivering 2 level event channels to a guest. Initially, it only supports delivery via the IRQ routing table, triggered by an eventfd. In order to do so, it has a kvm_xen_set_evtchn_fast() function which will use the pre-mapped shared_info page if it already exists and is still valid, while the slow path through the irqfd_inject workqueue will remap the shared_info page if necessary. It sets the bits in the shared_info page but not the vcpu_info; that is deferred to __kvm_xen_has_interrupt() which raises the vector to the appropriate vCPU. Add a 'verbose' mode to xen_shinfo_test while adding test cases for this. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20211210163625.2886-5-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86/xen: Maintain valid mapping of Xen shared_info pageDavid Woodhouse2022-01-071-0/+12
| | | | | | | | | | | | | | Use the newly reinstated gfn_to_pfn_cache to maintain a kernel mapping of the Xen shared_info page so that it can be accessed in atomic context. Note that we do not participate in dirty tracking for the shared info page and we do not explicitly mark it dirty every single tim we deliver an event channel interrupts. We wouldn't want to do that even if we *did* have a valid vCPU context with which to do so. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20211210163625.2886-4-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: s390: Fix names of skey constants in api documentationJanis Schoetterl-Glausch2021-12-071-3/+3
| | | | | | | | | | | | They are defined in include/uapi/linux/kvm.h as KVM_S390_GET_SKEYS_NONE and KVM_S390_SKEYS_MAX, but the api documetation talks of KVM_S390_GET_KEYS_NONE and KVM_S390_SKEYS_ALLOC_MAX respectively. Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Message-Id: <20211118102522.569660-1-scgl@linux.ibm.com> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
* KVM: SEV: Add support for SEV intra host migrationPeter Gonda2021-11-111-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <pgonda@google.com> Suggested-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Marc Orr <marcorr@google.com> Cc: Marc Orr <marcorr@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Wanpeng Li <wanpengli@tencent.com> Cc: Jim Mattson <jmattson@google.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Message-Id: <20211021174303.385706-3-pgonda@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: Report host tsc and realtime values in KVM_GET_CLOCKOliver Upton2021-10-181-9/+39
| | | | | | | | | | | | | | | | | | | | 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 <pbonzini@redhat.com> Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20210916181538.968978-5-oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* RISC-V: KVM: Document RISC-V specific parts of KVM APIAnup Patel2021-10-041-9/+184
| | | | | | | | | | | | | | | 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 <corbet@lwn.net> CC: linux-doc@vger.kernel.org Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
* Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2021-09-071-8/+28
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * KVM: x86: implement KVM_GUESTDBG_BLOCKIRQMaxim Levitsky2021-08-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <mlevitsk@redhat.com> Message-Id: <20210811122927.900604-6-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>