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2024-05-17Merge tag 'powerpc-6.10-1' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Enable BPF Kernel Functions (kfuncs) in the powerpc BPF JIT. - Allow per-process DEXCR (Dynamic Execution Control Register) settings via prctl, notably NPHIE which controls hashst/hashchk for ROP protection. - Install powerpc selftests in sub-directories. Note this changes the way run_kselftest.sh needs to be invoked for powerpc selftests. - Change fadump (Firmware Assisted Dump) to better handle memory add/remove. - Add support for passing additional parameters to the fadump kernel. - Add support for updating the kdump image on CPU/memory add/remove events. - Other small features, cleanups and fixes. Thanks to Andrew Donnellan, Andy Shevchenko, Aneesh Kumar K.V, Arnd Bergmann, Benjamin Gray, Bjorn Helgaas, Christian Zigotzky, Christophe Jaillet, Christophe Leroy, Colin Ian King, Cédric Le Goater, Dr. David Alan Gilbert, Erhard Furtner, Frank Li, GUO Zihua, Ganesh Goudar, Geoff Levand, Ghanshyam Agrawal, Greg Kurz, Hari Bathini, Joel Stanley, Justin Stitt, Kunwu Chan, Li Yang, Lidong Zhong, Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Matthias Schiffer, Naresh Kamboju, Nathan Chancellor, Nathan Lynch, Naveen N Rao, Nicholas Miehlbradt, Ran Wang, Randy Dunlap, Ritesh Harjani, Sachin Sant, Shirisha Ganta, Shrikanth Hegde, Sourabh Jain, Stephen Rothwell, sundar, Thorsten Blum, Vaibhav Jain, Xiaowei Bao, Yang Li, and Zhao Chenhui. * tag 'powerpc-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (85 commits) powerpc/fadump: Fix section mismatch warning powerpc/85xx: fix compile error without CONFIG_CRASH_DUMP powerpc/fadump: update documentation about bootargs_append powerpc/fadump: pass additional parameters when fadump is active powerpc/fadump: setup additional parameters for dump capture kernel powerpc/pseries/fadump: add support for multiple boot memory regions selftests/powerpc/dexcr: Fix spelling mistake "predicition" -> "prediction" KVM: PPC: Book3S HV nestedv2: Fix an error handling path in gs_msg_ops_kvmhv_nestedv2_config_fill_info() KVM: PPC: Fix documentation for ppc mmu caps KVM: PPC: code cleanup for kvmppc_book3s_irqprio_deliver KVM: PPC: Book3S HV nestedv2: Cancel pending DEC exception powerpc/xmon: Check cpu id in commands "c#", "dp#" and "dx#" powerpc/code-patching: Use dedicated memory routines for patching powerpc/code-patching: Test patch_instructions() during boot powerpc64/kasan: Pass virtual addresses to kasan_init_phys_region() powerpc: rename SPRN_HID2 define to SPRN_HID2_750FX powerpc: Fix typos powerpc/eeh: Fix spelling of the word "auxillary" and update comment macintosh/ams: Fix unused variable warning powerpc/Makefile: Remove bits related to the previous use of -mcmodel=large ...
2024-05-12Merge tag 'kvm-x86-generic-6.10' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini1-1/+1
KVM cleanups for 6.10: - Misc cleanups extracted from the "exit on missing userspace mapping" series, which has been put on hold in anticipation of a "KVM Userfault" approach, which should provide a superset of functionality. - Remove kvm_make_all_cpus_request_except(), which got added to hack around an AVIC bug, and then became dead code when a more robust fix came along. - Fix a goof in the KVM_CREATE_GUEST_MEMFD documentation.
2024-05-12Merge tag 'kvmarm-6.10-1' of ↵Paolo Bonzini5-150/+214
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for Linux 6.10 - Move a lot of state that was previously stored on a per vcpu basis into a per-CPU area, because it is only pertinent to the host while the vcpu is loaded. This results in better state tracking, and a smaller vcpu structure. - Add full handling of the ERET/ERETAA/ERETAB instructions in nested virtualisation. The last two instructions also require emulating part of the pointer authentication extension. As a result, the trap handling of pointer authentication has been greattly simplified. - Turn the global (and not very scalable) LPI translation cache into a per-ITS, scalable cache, making non directly injected LPIs much cheaper to make visible to the vcpu. - A batch of pKVM patches, mostly fixes and cleanups, as the upstreaming process seems to be resuming. Fingers crossed! - Allocate PPIs and SGIs outside of the vcpu structure, allowing for smaller EL2 mapping and some flexibility in implementing more or less than 32 private IRQs. - Purge stale mpidr_data if a vcpu is created after the MPIDR map has been created. - Preserve vcpu-specific ID registers across a vcpu reset. - Various minor cleanups and improvements.
2024-05-07KVM: SEV: Allow per-guest configuration of GHCB protocol versionMichael Roth1-2/+9
The GHCB protocol version may be different from one guest to the next. Add a field to track it for each KVM instance and extend KVM_SEV_INIT2 to allow it to be configured by userspace. Now that all SEV-ES support for GHCB protocol version 2 is in place, go ahead and default to it when creating SEV-ES guests through the new KVM_SEV_INIT2 interface. Keep the older KVM_SEV_ES_INIT interface restricted to GHCB protocol version 1. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Message-ID: <20240501071048.2208265-5-michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-05-07KVM: PPC: Fix documentation for ppc mmu capsJoel Stanley1-4/+4
The documentation mentions KVM_CAP_PPC_RADIX_MMU, but the defines in the kvm headers spell it KVM_CAP_PPC_MMU_RADIX. Similarly with KVM_CAP_PPC_MMU_HASH_V3. Fixes: c92701322711 ("KVM: PPC: Book3S HV: Add userspace interfaces for POWER9 MMU") Signed-off-by: Joel Stanley <joel@jms.id.au> Acked-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230411061446.26324-1-joel@jms.id.au
2024-05-04KVM: fix documentation for KVM_CREATE_GUEST_MEMFDCarlos López1-1/+1
The KVM_CREATE_GUEST_MEMFD ioctl returns a file descriptor, and is documented as such in the description. However, the "Returns" field in the documentation states that the ioctl returns 0 on success. Update this to match the description. Signed-off-by: Carlos López <clopez@suse.de> Fixes: a7800aa80ea4 ("KVM: Add KVM_CREATE_GUEST_MEMFD ioctl() for guest-specific backing memory") Link: https://lore.kernel.org/r/20240424103317.28522-1-clopez@suse.de Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-05-03Merge branch kvm-arm64/pkvm-6.10 into kvmarm-master/nextMarc Zyngier5-150/+214
* kvm-arm64/pkvm-6.10: (25 commits) : . : At last, a bunch of pKVM patches, courtesy of Fuad Tabba. : From the cover letter: : : "This series is a bit of a bombay-mix of patches we've been : carrying. There's no one overarching theme, but they do improve : the code by fixing existing bugs in pKVM, refactoring code to : make it more readable and easier to re-use for pKVM, or adding : functionality to the existing pKVM code upstream." : . KVM: arm64: Force injection of a data abort on NISV MMIO exit KVM: arm64: Restrict supported capabilities for protected VMs KVM: arm64: Refactor setting the return value in kvm_vm_ioctl_enable_cap() KVM: arm64: Document the KVM/arm64-specific calls in hypercalls.rst KVM: arm64: Rename firmware pseudo-register documentation file KVM: arm64: Reformat/beautify PTP hypercall documentation KVM: arm64: Clarify rationale for ZCR_EL1 value restored on guest exit KVM: arm64: Introduce and use predicates that check for protected VMs KVM: arm64: Add is_pkvm_initialized() helper KVM: arm64: Simplify vgic-v3 hypercalls KVM: arm64: Move setting the page as dirty out of the critical section KVM: arm64: Change kvm_handle_mmio_return() return polarity KVM: arm64: Fix comment for __pkvm_vcpu_init_traps() KVM: arm64: Prevent kmemleak from accessing .hyp.data KVM: arm64: Do not map the host fpsimd state to hyp in pKVM KVM: arm64: Rename __tlb_switch_to_{guest,host}() in VHE KVM: arm64: Support TLB invalidation in guest context KVM: arm64: Avoid BBM when changing only s/w bits in Stage-2 PTE KVM: arm64: Check for PTE validity when checking for executable/cacheable KVM: arm64: Avoid BUG-ing from the host abort path ... Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-05-01KVM: arm64: Force injection of a data abort on NISV MMIO exitMarc Zyngier1-0/+7
If a vcpu exits for a data abort with an invalid syndrome, the expectations are that userspace has a chance to save the day if it has requested to see such exits. However, this is completely futile in the case of a protected VM, as none of the state is available. In this particular case, inject a data abort directly into the vcpu, consistent with what userspace could do. This also helps with pKVM, which discards all syndrome information when forwarding data aborts that are not known to be MMIO. Finally, document this tweak to the API. Signed-off-by: Fuad Tabba <tabba@google.com> Acked-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240423150538.2103045-31-tabba@google.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-05-01KVM: arm64: Document the KVM/arm64-specific calls in hypercalls.rstWill Deacon2-0/+47
KVM/arm64 makes use of the SMCCC "Vendor Specific Hypervisor Service Call Range" to expose KVM-specific hypercalls to guests in a discoverable and extensible fashion. Document the existence of this interface and the discovery hypercall. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Fuad Tabba <tabba@google.com> Acked-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240423150538.2103045-28-tabba@google.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-05-01KVM: arm64: Rename firmware pseudo-register documentation fileWill Deacon2-4/+4
In preparation for describing the guest view of KVM/arm64 hypercalls in hypercalls.rst, move the existing contents of the file concerning the firmware pseudo-registers elsewhere. Cc: Raghavendra Rao Ananta <rananta@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Fuad Tabba <tabba@google.com> Acked-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240423150538.2103045-27-tabba@google.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-05-01KVM: arm64: Reformat/beautify PTP hypercall documentationWill Deacon1-14/+24
The PTP hypercall documentation doesn't produce the best-looking table when formatting in HTML as all of the return value definitions end up on the same line. Reformat the PTP hypercall documentation to follow the formatting used by hypercalls.rst. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Fuad Tabba <tabba@google.com> Acked-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240423150538.2103045-26-tabba@google.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-04-11KVM: SEV: introduce KVM_SEV_INIT2 operationPaolo Bonzini1-3/+37
The idea that no parameter would ever be necessary when enabling SEV or SEV-ES for a VM was decidedly optimistic. In fact, in some sense it's already a parameter whether SEV or SEV-ES is desired. Another possible source of variability is the desired set of VMSA features, as that affects the measurement of the VM's initial state and cannot be changed arbitrarily by the hypervisor. Create a new sub-operation for KVM_MEMORY_ENCRYPT_OP that can take a struct, and put the new op to work by including the VMSA features as a field of the struct. The existing KVM_SEV_INIT and KVM_SEV_ES_INIT use the full set of supported VMSA features for backwards compatibility. The struct also includes the usual bells and whistles for future extensibility: a flags field that must be zero for now, and some padding at the end. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20240404121327.3107131-13-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-11KVM: SEV: define VM types for SEV and SEV-ESPaolo Bonzini1-0/+2
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20240404121327.3107131-11-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-11KVM: SEV: publish supported VMSA featuresPaolo Bonzini1-0/+12
Compute the set of features to be stored in the VMSA when KVM is initialized; move it from there into kvm_sev_info when SEV is initialized, and then into the initial VMSA. The new variable can then be used to return the set of supported features to userspace, via the KVM_GET_DEVICE_ATTR ioctl. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com> Message-ID: <20240404121327.3107131-6-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-19Documentation: kvm/sev: clarify usage of KVM_MEMORY_ENCRYPT_OPPaolo Bonzini1-6/+7
Explain that it operates on the VM file descriptor, and also clarify how detection of SEV operates on old kernels predating commit 2da1ed62d55c ("KVM: SVM: document KVM_MEM_ENCRYPT_OP, let userspace detect if SEV is available"). Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-19Documentation: kvm/sev: separate description of firmwarePaolo Bonzini1-12/+17
The description of firmware is included part under the "SEV Key Management" header, part under the KVM_SEV_INIT ioctl. Put these two bits together and and rename "SEV Key Management" to what it actually is, namely a description of the KVM_MEMORY_ENCRYPT_OP API. Reviewed-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-19Merge tag 'kvm-x86-asyncpf_abi-6.9' of https://github.com/kvm-x86/linux into ↵Paolo Bonzini1-10/+9
HEAD Guest-side KVM async #PF ABI cleanup for 6.9 Delete kvm_vcpu_pv_apf_data.enabled to fix a goof in KVM's async #PF ABI where the enabled field pushes the size of "struct kvm_vcpu_pv_apf_data" from 64 to 68 bytes, i.e. beyond a single cache line. The enabled field is purely a guest-side flag that Linux-as-a-guest uses to track whether or not the guest has enabled async #PF support. The actual flag that is passed to the host, i.e. to KVM proper, is a single bit in a synthetic MSR, MSR_KVM_ASYNC_PF_EN, i.e. is in a location completely unrelated to the shared kvm_vcpu_pv_apf_data structure. Simply drop the the field and use a dedicated guest-side per-CPU variable to fix the ABI, as opposed to fixing the documentation to match reality. KVM has never consumed kvm_vcpu_pv_apf_data.enabled, so the odds of the ABI change breaking anything are extremely low.
2024-03-11Merge tag 'kvm-x86-xen-6.9' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini1-12/+41
KVM Xen and pfncache changes for 6.9: - Rip out the half-baked support for using gfn_to_pfn caches to manage pages that are "mapped" into guests via physical addresses. - Add support for using gfn_to_pfn caches with only a host virtual address, i.e. to bypass the "gfn" stage of the cache. The primary use case is overlay pages, where the guest may change the gfn used to reference the overlay page, but the backing hva+pfn remains the same. - Add an ioctl() to allow mapping Xen's shared_info page using an hva instead of a gpa, so that userspace doesn't need to reconfigure and invalidate the cache/mapping if the guest changes the gpa (but userspace keeps the resolved hva the same). - When possible, use a single host TSC value when computing the deadline for Xen timers in order to improve the accuracy of the timer emulation. - Inject pending upcall events when the vCPU software-enables its APIC to fix a bug where an upcall can be lost (and to follow Xen's behavior). - Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen events fails, e.g. if the guest has aliased xAPIC IDs. - Extend gfn_to_pfn_cache's mutex to cover (de)activation (in addition to refresh), and drop a now-redundant acquisition of xen_lock (that was protecting the shared_info cache) to fix a deadlock due to recursively acquiring xen_lock.
2024-02-23KVM: x86: Update KVM_SW_PROTECTED_VM docs to make it clear they're a WIPSean Christopherson1-0/+5
Rewrite the help message for KVM_SW_PROTECTED_VM to make it clear that software-protected VMs are a development and testing vehicle for guest_memfd(), and that attempting to use KVM_SW_PROTECTED_VM for anything remotely resembling a "real" VM will fail. E.g. any memory accesses from KVM will incorrectly access shared memory, nested TDP is wildly broken, and so on and so forth. Update KVM's API documentation with similar warnings to discourage anyone from attempting to run anything but selftests with KVM_X86_SW_PROTECTED_VM. Fixes: 89ea60c2c7b5 ("KVM: x86: Add support for "protected VMs" that can utilize private memory") Link: https://lore.kernel.org/r/20240222190612.2942589-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22KVM: x86/xen: allow vcpu_info to be mapped by fixed HVAPaul Durrant1-5/+21
If the guest does not explicitly set the GPA of vcpu_info structure in memory then, for guests with 32 vCPUs or fewer, the vcpu_info embedded in the shared_info page may be used. As described in a previous commit, the shared_info page is an overlay at a fixed HVA within the VMM, so in this case it also more optimal to activate the vcpu_info cache with a fixed HVA to avoid unnecessary invalidation if the guest memory layout is modified. Signed-off-by: Paul Durrant <pdurrant@amazon.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20240215152916.1158-14-paul@xen.org [sean: use kvm_gpc_is_{gpa,hva}_active()] Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22KVM: x86/xen: allow shared_info to be mapped by fixed HVAPaul Durrant1-6/+19
The shared_info page is not guest memory as such. It is a dedicated page allocated by the VMM and overlaid onto guest memory in a GFN chosen by the guest and specified in the XENMEM_add_to_physmap hypercall. The guest may even request that shared_info be moved from one GFN to another by re-issuing that hypercall, but the HVA is never going to change. Because the shared_info page is an overlay the memory slots need to be updated in response to the hypercall. However, memory slot adjustment is not atomic and, whilst all vCPUs are paused, there is still the possibility that events may be delivered (which requires the shared_info page to be updated) whilst the shared_info GPA is absent. The HVA is never absent though, so it makes much more sense to use that as the basis for the kernel's mapping. Hence add a new KVM_XEN_ATTR_TYPE_SHARED_INFO_HVA attribute type for this purpose and a KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA flag to advertize its availability. Don't actually advertize it yet though. That will be done in a subsequent patch, which will also add tests for the new attribute type. Also update the KVM API documentation with the new attribute and also fix it up to consistently refer to 'shared_info' (with the underscore). Signed-off-by: Paul Durrant <pdurrant@amazon.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20240215152916.1158-13-paul@xen.org [sean: store "hva" as a user pointer, use kvm_gpc_is_{gpa,hva}_active()] Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-06KVM: x86: Improve documentation of MSR_KVM_ASYNC_PF_ENXiaoyao Li1-9/+9
Fix some incorrect statement of MSR_KVM_ASYNC_PF_EN documentation and state clearly the token in 'struct kvm_vcpu_pv_apf_data' of 'page ready' event is matchted with the token in CR2 in 'page not present' event. Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20231025055914.1201792-3-xiaoyao.li@intel.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-06x86/kvm: Use separate percpu variable to track the enabling of asyncpfXiaoyao Li1-1/+0
Refer to commit fd10cde9294f ("KVM paravirt: Add async PF initialization to PV guest") and commit 344d9588a9df ("KVM: Add PV MSR to enable asynchronous page faults delivery"). It turns out that at the time when asyncpf was introduced, the purpose was defining the shared PV data 'struct kvm_vcpu_pv_apf_data' with the size of 64 bytes. However, it made a mistake and defined the size to 68 bytes, which failed to make fit in a cache line and made the code inconsistent with the documentation. Below justification quoted from Sean[*] KVM (the host side) has *never* read kvm_vcpu_pv_apf_data.enabled, and the documentation clearly states that enabling is based solely on the bit in the synthetic MSR. So rather than update the documentation, fix the goof by removing the enabled filed and use the separate percpu variable instread. KVM-as-a-host obviously doesn't enforce anything or consume the size, and changing the header will only affect guests that are rebuilt against the new header, so there's no chance of ABI breakage between KVM and its guests. The only possible breakage is if some other hypervisor is emulating KVM's async #PF (LOL) and relies on the guest to set kvm_vcpu_pv_apf_data.enabled. But (a) I highly doubt such a hypervisor exists, (b) that would arguably be a violation of KVM's "spec", and (c) the worst case scenario is that the guest would simply lose async #PF functionality. [*] https://lore.kernel.org/all/ZS7ERnnRqs8Fl0ZF@google.com/T/#u Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20231025055914.1201792-2-xiaoyao.li@intel.com [sean: use true/false instead of 1/0 for booleans] Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-01-08Merge tag 'kvm-x86-mmu-6.8' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini1-4/+3
KVM x86 MMU changes for 6.8: - Fix a relatively benign off-by-one error when splitting huge pages during CLEAR_DIRTY_LOG. - Fix a bug where KVM could incorrectly test-and-clear dirty bits in non-leaf TDP MMU SPTEs if a racing thread replaces a huge SPTE with a non-huge SPTE. - Relax the TDP MMU's lockdep assertions related to holding mmu_lock for read versus write so that KVM doesn't pass "bool shared" all over the place just to have precise assertions in paths that don't actually care about whether the caller is a reader or a writer.
2024-01-08Merge tag 'kvm-x86-xen-6.8' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini1-0/+6
KVM Xen change for 6.8: To workaround Xen guests that don't expect Xen PV clocks to be marked as being based on a stable TSC, add a Xen config knob to allow userspace to opt out of KVM setting the "TSC stable" bit in Xen PV clocks. Note, the "TSC stable" bit was added to the PVCLOCK ABI by KVM without an ack from Xen, i.e. KVM isn't entirely blameless for the buggy guest behavior.
2023-12-08KVM: remove deprecated UAPIsPaolo Bonzini1-12/+0
The deprecated interfaces were removed 15 years ago. KVM's device assignment was deprecated in 4.2 and removed 6.5 years ago; the only interest might be in compiling ancient versions of QEMU, but QEMU has been using its own imported copy of the kernel headers since June 2011. So again we go into archaeology territory; just remove the cruft. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-12-08KVM x86/xen: add an override for PVCLOCK_TSC_STABLE_BITPaul Durrant1-0/+6
Unless explicitly told to do so (by passing 'clocksource=tsc' and 'tsc=stable:socket', and then jumping through some hoops concerning potential CPU hotplug) Xen will never use TSC as its clocksource. Hence, by default, a Xen guest will not see PVCLOCK_TSC_STABLE_BIT set in either the primary or secondary pvclock memory areas. This has led to bugs in some guest kernels which only become evident if PVCLOCK_TSC_STABLE_BIT *is* set in the pvclocks. Hence, to support such guests, give the VMM a new Xen HVM config flag to tell KVM to forcibly clear the bit in the Xen pvclocks. Signed-off-by: Paul Durrant <pdurrant@amazon.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20231102162128.2353459-1-paul@xen.org Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-12-01KVM: x86/mmu: always take tdp_mmu_pages_lockPaolo Bonzini1-4/+3
It is cheap to take tdp_mmu_pages_lock in all write-side critical sections. We already do it all the time when zapping with read_lock(), so it is not a problem to do it from the kvm_tdp_mmu_zap_all() path (aka kvm_arch_flush_shadow_all(), aka VM destruction and MMU notifier release). Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Link: https://lore.kernel.org/r/20231125083400.1399197-4-pbonzini@redhat.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-11-14KVM: x86: Add support for "protected VMs" that can utilize private memorySean Christopherson1-0/+32
Add a new x86 VM type, KVM_X86_SW_PROTECTED_VM, to serve as a development and testing vehicle for Confidential (CoCo) VMs, and potentially to even become a "real" product in the distant future, e.g. a la pKVM. The private memory support in KVM x86 is aimed at AMD's SEV-SNP and Intel's TDX, but those technologies are extremely complex (understatement), difficult to debug, don't support running as nested guests, and require hardware that's isn't universally accessible. I.e. relying SEV-SNP or TDX for maintaining guest private memory isn't a realistic option. At the very least, KVM_X86_SW_PROTECTED_VM will enable a variety of selftests for guest_memfd and private memory support without requiring unique hardware. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20231027182217.3615211-24-seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-14KVM: x86/mmu: Handle page fault for private memoryChao Peng1-2/+6
Add support for resolving page faults on guest private memory for VMs that differentiate between "shared" and "private" memory. For such VMs, KVM_MEM_GUEST_MEMFD memslots can include both fd-based private memory and hva-based shared memory, and KVM needs to map in the "correct" variant, i.e. KVM needs to map the gfn shared/private as appropriate based on the current state of the gfn's KVM_MEMORY_ATTRIBUTE_PRIVATE flag. For AMD's SEV-SNP and Intel's TDX, the guest effectively gets to request shared vs. private via a bit in the guest page tables, i.e. what the guest wants may conflict with the current memory attributes. To support such "implicit" conversion requests, exit to user with KVM_EXIT_MEMORY_FAULT to forward the request to userspace. Add a new flag for memory faults, KVM_MEMORY_EXIT_FLAG_PRIVATE, to communicate whether the guest wants to map memory as shared vs. private. Like KVM_MEMORY_ATTRIBUTE_PRIVATE, use bit 3 for flagging private memory so that KVM can use bits 0-2 for capturing RWX behavior if/when userspace needs such information, e.g. a likely user of KVM_EXIT_MEMORY_FAULT is to exit on missing mappings when handling guest page fault VM-Exits. In that case, userspace will want to know RWX information in order to correctly/precisely resolve the fault. Note, private memory *must* be backed by guest_memfd, i.e. shared mappings always come from the host userspace page tables, and private mappings always come from a guest_memfd instance. Co-developed-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-21-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-14KVM: Add KVM_CREATE_GUEST_MEMFD ioctl() for guest-specific backing memorySean Christopherson1-2/+68
Introduce an ioctl(), KVM_CREATE_GUEST_MEMFD, to allow creating file-based memory that is tied to a specific KVM virtual machine and whose primary purpose is to serve guest memory. A guest-first memory subsystem allows for optimizations and enhancements that are kludgy or outright infeasible to implement/support in a generic memory subsystem. With guest_memfd, guest protections and mapping sizes are fully decoupled from host userspace mappings. E.g. KVM currently doesn't support mapping memory as writable in the guest without it also being writable in host userspace, as KVM's ABI uses VMA protections to define the allow guest protection. Userspace can fudge this by establishing two mappings, a writable mapping for the guest and readable one for itself, but that’s suboptimal on multiple fronts. Similarly, KVM currently requires the guest mapping size to be a strict subset of the host userspace mapping size, e.g. KVM doesn’t support creating a 1GiB guest mapping unless userspace also has a 1GiB guest mapping. Decoupling the mappings sizes would allow userspace to precisely map only what is needed without impacting guest performance, e.g. to harden against unintentional accesses to guest memory. Decoupling guest and userspace mappings may also allow for a cleaner alternative to high-granularity mappings for HugeTLB, which has reached a bit of an impasse and is unlikely to ever be merged. A guest-first memory subsystem also provides clearer line of sight to things like a dedicated memory pool (for slice-of-hardware VMs) and elimination of "struct page" (for offload setups where userspace _never_ needs to mmap() guest memory). More immediately, being able to map memory into KVM guests without mapping said memory into the host is critical for Confidential VMs (CoCo VMs), the initial use case for guest_memfd. While AMD's SEV and Intel's TDX prevent untrusted software from reading guest private data by encrypting guest memory with a key that isn't usable by the untrusted host, projects such as Protected KVM (pKVM) provide confidentiality and integrity *without* relying on memory encryption. And with SEV-SNP and TDX, accessing guest private memory can be fatal to the host, i.e. KVM must be prevent host userspace from accessing guest memory irrespective of hardware behavior. Attempt #1 to support CoCo VMs was to add a VMA flag to mark memory as being mappable only by KVM (or a similarly enlightened kernel subsystem). That approach was abandoned largely due to it needing to play games with PROT_NONE to prevent userspace from accessing guest memory. Attempt #2 to was to usurp PG_hwpoison to prevent the host from mapping guest private memory into userspace, but that approach failed to meet several requirements for software-based CoCo VMs, e.g. pKVM, as the kernel wouldn't easily be able to enforce a 1:1 page:guest association, let alone a 1:1 pfn:gfn mapping. And using PG_hwpoison does not work for memory that isn't backed by 'struct page', e.g. if devices gain support for exposing encrypted memory regions to guests. Attempt #3 was to extend the memfd() syscall and wrap shmem to provide dedicated file-based guest memory. That approach made it as far as v10 before feedback from Hugh Dickins and Christian Brauner (and others) led to it demise. Hugh's objection was that piggybacking shmem made no sense for KVM's use case as KVM didn't actually *want* the features provided by shmem. I.e. KVM was using memfd() and shmem to avoid having to manage memory directly, not because memfd() and shmem were the optimal solution, e.g. things like read/write/mmap in shmem were dead weight. Christian pointed out flaws with implementing a partial overlay (wrapping only _some_ of shmem), e.g. poking at inode_operations or super_operations would show shmem stuff, but address_space_operations and file_operations would show KVM's overlay. Paraphrashing heavily, Christian suggested KVM stop being lazy and create a proper API. Link: https://lore.kernel.org/all/20201020061859.18385-1-kirill.shutemov@linux.intel.com Link: https://lore.kernel.org/all/20210416154106.23721-1-kirill.shutemov@linux.intel.com Link: https://lore.kernel.org/all/20210824005248.200037-1-seanjc@google.com Link: https://lore.kernel.org/all/20211111141352.26311-1-chao.p.peng@linux.intel.com Link: https://lore.kernel.org/all/20221202061347.1070246-1-chao.p.peng@linux.intel.com Link: https://lore.kernel.org/all/ff5c5b97-acdf-9745-ebe5-c6609dd6322e@google.com Link: https://lore.kernel.org/all/20230418-anfallen-irdisch-6993a61be10b@brauner Link: https://lore.kernel.org/all/ZEM5Zq8oo+xnApW9@google.com Link: https://lore.kernel.org/linux-mm/20230306191944.GA15773@monkey Link: https://lore.kernel.org/linux-mm/ZII1p8ZHlHaQ3dDl@casper.infradead.org Cc: Fuad Tabba <tabba@google.com> Cc: Vishal Annapurve <vannapurve@google.com> Cc: Ackerley Tng <ackerleytng@google.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Maciej Szmigiero <mail@maciej.szmigiero.name> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Hildenbrand <david@redhat.com> Cc: Quentin Perret <qperret@google.com> Cc: Michael Roth <michael.roth@amd.com> Cc: Wang <wei.w.wang@intel.com> Cc: Liam Merwick <liam.merwick@oracle.com> Cc: Isaku Yamahata <isaku.yamahata@gmail.com> Co-developed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Co-developed-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com> Co-developed-by: Chao Peng <chao.p.peng@linux.intel.com> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Co-developed-by: Ackerley Tng <ackerleytng@google.com> Signed-off-by: Ackerley Tng <ackerleytng@google.com> Co-developed-by: Isaku Yamahata <isaku.yamahata@intel.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Co-developed-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20231027182217.3615211-17-seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-13KVM: Introduce per-page memory attributesChao Peng1-0/+36
In confidential computing usages, whether a page is private or shared is necessary information for KVM to perform operations like page fault handling, page zapping etc. There are other potential use cases for per-page memory attributes, e.g. to make memory read-only (or no-exec, or exec-only, etc.) without having to modify memslots. Introduce the KVM_SET_MEMORY_ATTRIBUTES ioctl, advertised by KVM_CAP_MEMORY_ATTRIBUTES, to allow userspace to set the per-page memory attributes to a guest memory range. Use an xarray to store the per-page attributes internally, with a naive, not fully optimized implementation, i.e. prioritize correctness over performance for the initial implementation. Use bit 3 for the PRIVATE attribute so that KVM can use bits 0-2 for RWX attributes/protections in the future, e.g. to give userspace fine-grained control over read, write, and execute protections for guest memory. Provide arch hooks for handling attribute changes before and after common code sets the new attributes, e.g. x86 will use the "pre" hook to zap all relevant mappings, and the "post" hook to track whether or not hugepages can be used to map the range. To simplify the implementation wrap the entire sequence with kvm_mmu_invalidate_{begin,end}() even though the operation isn't strictly guaranteed to be an invalidation. For the initial use case, x86 *will* always invalidate memory, and preventing arch code from creating new mappings while the attributes are in flux makes it much easier to reason about the correctness of consuming attributes. It's possible that future usages may not require an invalidation, e.g. if KVM ends up supporting RWX protections and userspace grants _more_ protections, but again opt for simplicity and punt optimizations to if/when they are needed. Suggested-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/all/Y2WB48kD0J4VGynX@google.com Cc: Fuad Tabba <tabba@google.com> Cc: Xu Yilun <yilun.xu@intel.com> Cc: Mickaël Salaün <mic@digikod.net> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20231027182217.3615211-14-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-13KVM: Add KVM_EXIT_MEMORY_FAULT exit to report faults to userspaceChao Peng1-0/+41
Add a new KVM exit type to allow userspace to handle memory faults that KVM cannot resolve, but that userspace *may* be able to handle (without terminating the guest). KVM will initially use KVM_EXIT_MEMORY_FAULT to report implicit conversions between private and shared memory. With guest private memory, there will be two kind of memory conversions: - explicit conversion: happens when the guest explicitly calls into KVM to map a range (as private or shared) - implicit conversion: happens when the guest attempts to access a gfn that is configured in the "wrong" state (private vs. shared) On x86 (first architecture to support guest private memory), explicit conversions will be reported via KVM_EXIT_HYPERCALL+KVM_HC_MAP_GPA_RANGE, but reporting KVM_EXIT_HYPERCALL for implicit conversions is undesriable as there is (obviously) no hypercall, and there is no guarantee that the guest actually intends to convert between private and shared, i.e. what KVM thinks is an implicit conversion "request" could actually be the result of a guest code bug. KVM_EXIT_MEMORY_FAULT will be used to report memory faults that appear to be implicit conversions. Note! To allow for future possibilities where KVM reports KVM_EXIT_MEMORY_FAULT and fills run->memory_fault on _any_ unresolved fault, KVM returns "-EFAULT" (-1 with errno == EFAULT from userspace's perspective), not '0'! Due to historical baggage within KVM, exiting to userspace with '0' from deep callstacks, e.g. in emulation paths, is infeasible as doing so would require a near-complete overhaul of KVM, whereas KVM already propagates -errno return codes to userspace even when the -errno originated in a low level helper. Report the gpa+size instead of a single gfn even though the initial usage is expected to always report single pages. It's entirely possible, likely even, that KVM will someday support sub-page granularity faults, e.g. Intel's sub-page protection feature allows for additional protections at 128-byte granularity. Link: https://lore.kernel.org/all/20230908222905.1321305-5-amoorthy@google.com Link: https://lore.kernel.org/all/ZQ3AmLO2SYv3DszH@google.com Cc: Anish Moorthy <amoorthy@google.com> Cc: David Matlack <dmatlack@google.com> Suggested-by: Sean Christopherson <seanjc@google.com> Co-developed-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20231027182217.3615211-10-seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-13KVM: Introduce KVM_SET_USER_MEMORY_REGION2Sean Christopherson1-0/+22
Introduce a "version 2" of KVM_SET_USER_MEMORY_REGION so that additional information can be supplied without setting userspace up to fail. The padding in the new kvm_userspace_memory_region2 structure will be used to pass a file descriptor in addition to the userspace_addr, i.e. allow userspace to point at a file descriptor and map memory into a guest that is NOT mapped into host userspace. Alternatively, KVM could simply add "struct kvm_userspace_memory_region2" without a new ioctl(), but as Paolo pointed out, adding a new ioctl() makes detection of bad flags a bit more robust, e.g. if the new fd field is guarded only by a flag and not a new ioctl(), then a userspace bug (setting a "bad" flag) would generate out-of-bounds access instead of an -EINVAL error. Cc: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-9-seanjc@google.com> Acked-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-10-31Merge tag 'kvmarm-6.7' of ↵Paolo Bonzini4-0/+108
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for 6.7 - Generalized infrastructure for 'writable' ID registers, effectively allowing userspace to opt-out of certain vCPU features for its guest - Optimization for vSGI injection, opportunistically compressing MPIDR to vCPU mapping into a table - Improvements to KVM's PMU emulation, allowing userspace to select the number of PMCs available to a VM - Guest support for memory operation instructions (FEAT_MOPS) - Cleanups to handling feature flags in KVM_ARM_VCPU_INIT, squashing bugs and getting rid of useless code - Changes to the way the SMCCC filter is constructed, avoiding wasted memory allocations when not in use - Load the stage-2 MMU context at vcpu_load() for VHE systems, reducing the overhead of errata mitigations - Miscellaneous kernel and selftest fixes
2023-10-31Merge tag 'kvm-x86-docs-6.7' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini2-18/+61
KVM x86 Documentation updates for 6.7: - Fix various typos, notably a confusing reference to the non-existent "struct kvm_vcpu_event" (the actual structure is kvm_vcpu_events, plural). - Update x86's kvm_mmu_page documentation to bring it closer to the code (this raced with the removal of async zapping and so the documentation is already stale; my bad). - Document the behavior of x86 PMU filters on fixed counters.
2023-10-30Merge branch kvm-arm64/writable-id-regs into kvmarm/nextOliver Upton3-0/+101
* kvm-arm64/writable-id-regs: : Writable ID registers, courtesy of Jing Zhang : : This series significantly expands the architectural feature set that : userspace can manipulate via the ID registers. A new ioctl is defined : that makes the mutable fields in the ID registers discoverable to : userspace. KVM: selftests: Avoid using forced target for generating arm64 headers tools headers arm64: Fix references to top srcdir in Makefile KVM: arm64: selftests: Test for setting ID register from usersapce tools headers arm64: Update sysreg.h with kernel sources KVM: selftests: Generate sysreg-defs.h and add to include path perf build: Generate arm64's sysreg-defs.h and add to include path tools: arm64: Add a Makefile for generating sysreg-defs.h KVM: arm64: Document vCPU feature selection UAPIs KVM: arm64: Allow userspace to change ID_AA64ZFR0_EL1 KVM: arm64: Allow userspace to change ID_AA64PFR0_EL1 KVM: arm64: Allow userspace to change ID_AA64MMFR{0-2}_EL1 KVM: arm64: Allow userspace to change ID_AA64ISAR{0-2}_EL1 KVM: arm64: Bump up the default KVM sanitised debug version to v8p8 KVM: arm64: Reject attempts to set invalid debug arch version KVM: arm64: Advertise selected DebugVer in DBGDIDR.Version KVM: arm64: Use guest ID register values for the sake of emulation KVM: arm64: Document KVM_ARM_GET_REG_WRITABLE_MASKS KVM: arm64: Allow userspace to get the writable masks for feature ID registers Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-10-04KVM: arm64: Document vCPU feature selection UAPIsOliver Upton3-0/+53
KVM/arm64 has a couple schemes for handling vCPU feature selection now, which is a lot to put on userspace. Add some documentation about how these interact and provide some recommendations for how to use the writable ID register scheme. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20231003230408.3405722-11-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-10-04KVM: arm64: Document KVM_ARM_GET_REG_WRITABLE_MASKSJing Zhang1-0/+48
Add some basic documentation on how to get feature ID register writable masks from userspace. Signed-off-by: Jing Zhang <jingzhangos@google.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20231003230408.3405722-3-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-10-02LoongArch: KVM: Supplement kvm document about LoongArch-specific partTianrui Zhao1-9/+61
Supplement kvm document about LoongArch-specific part, such as add api introduction for GET/SET_ONE_REG, GET/SET_FPU, GET/SET_MP_STATE, etc. Reviewed-by: Huacai Chen <chenhuacai@loongson.cn> Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-09-30KVM: arm64: Clarify the ordering requirements for vcpu/RD creationMarc Zyngier1-0/+7
It goes without saying, but it is probably better to spell it out: If userspace tries to restore and VM, but creates vcpus and/or RDs in a different order, the vcpu/RD mapping will be different. Yes, our API is an ugly piece of crap and I can't believe that we missed this. If we want to relax the above, we'll need to define a new userspace API that allows the mapping to be specified, rather than relying on the kernel to perform the mapping on its own. Reviewed-by: Zenghui Yu <yuzenghui@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230927090911.3355209-12-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-09-28KVM: x86/pmu: Add documentation for fixed ctr on PMU filterJinrong Liang1-0/+18
Update the documentation for the KVM_SET_PMU_EVENT_FILTER ioctl to include a detailed description of how fixed performance events are handled in the pmu filter. The action and fixed_counter_bitmap members of the pmu filter to determine whether fixed performance events can be programmed by the guest. This information is helpful for correctly configuring the fixed_counter_bitmap and action fields to filter fixed performance events. Suggested-by: Like Xu <likexu@tencent.com> Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/oe-kbuild-all/202304150850.rx4UDDsB-lkp@intel.com Signed-off-by: Jinrong Liang <cloudliang@tencent.com> Link: https://lore.kernel.org/r/20230531075052.43239-1-cloudliang@tencent.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-09-27KVM: Documentation: Add the missing description for tdp_mmu_page into ↵Mingwei Zhang1-0/+4
kvm_mmu_page Add the description for tdp_mmu_page into kvm_mmu_page description. tdp_mmu_page is a field to differentiate shadow pages from TDP MMU and non-TDP MMU. Signed-off-by: Mingwei Zhang <mizhang@google.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230912184553.1887764-7-mizhang@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-09-27KVM: Documentation: Add the missing description for mmu_valid_gen into ↵Mingwei Zhang1-0/+10
kvm_mmu_page Add the description for mmu_valid_gen into kvm_mmu_page description. mmu_valid_gen is used in shadow MMU for fast zapping. Update the doc to reflect that. Signed-off-by: Mingwei Zhang <mizhang@google.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230912184553.1887764-6-mizhang@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-09-27KVM: Documentation: Add the missing description for tdp_mmu_root_count into ↵Mingwei Zhang1-4/+7
kvm_mmu_page Add the description of tdp_mmu_root_count into kvm_mmu_page description and combine it with the description of root_count. tdp_mmu_root_count is an atomic counter used only in TDP MMU. Update the doc. Signed-off-by: Mingwei Zhang <mizhang@google.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230912184553.1887764-5-mizhang@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-09-27KVM: Documentation: Add the missing description for ptep in kvm_mmu_pageMingwei Zhang1-0/+3
Add the missing description for ptep in kvm_mmu_page description. ptep is used when TDP MMU is enabled and it shares the storage with parent_ptes. Update the doc to help readers to get up-to-date info. Signed-off-by: Mingwei Zhang <mizhang@google.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230912184553.1887764-4-mizhang@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-09-27KVM: Documentation: Update the field name gfns and its description in ↵Mingwei Zhang1-5/+8
kvm_mmu_page Update the field 'gfns' in kvm_mmu_page to 'shadowed_translation' to be consistent with the code. Also update the corresponding 'gfns' in the comments. The more detailed description of 'shadowed_translation' is already inlined in the data structure definition, so no need to duplicate the text but simply just update the names. Signed-off-by: Mingwei Zhang <mizhang@google.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230912184553.1887764-3-mizhang@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-09-27KVM: Documentation: Add the missing description for guest_mode in ↵Mingwei Zhang1-0/+2
kvm_mmu_page_role Add the missing description for guest_mode in kvm_mmu_page_role description. guest_mode tells KVM whether a shadow page is used for the L1 or an L2. Update the missing field in documentation. Signed-off-by: Mingwei Zhang <mizhang@google.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230912184553.1887764-2-mizhang@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-09-27KVM: Correct kvm_vcpu_event(s) typo in KVM API documentationMichal Luczaj1-9/+9
Set KVM_GET_VCPU_EVENTS and KVM_SET_VCPU_EVENTS parameter type to `struct kvm_vcpu_events`. Events, plural. Opportunistically fix few other typos. Signed-off-by: Michal Luczaj <mhal@rbox.co> Link: https://lore.kernel.org/r/20230814222358.707877-4-mhal@rbox.co Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-09-07Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-1/+3
Pull kvm updates from Paolo Bonzini: "ARM: - Clean up vCPU targets, always returning generic v8 as the preferred target - Trap forwarding infrastructure for nested virtualization (used for traps that are taken from an L2 guest and are needed by the L1 hypervisor) - FEAT_TLBIRANGE support to only invalidate specific ranges of addresses when collapsing a table PTE to a block PTE. This avoids that the guest refills the TLBs again for addresses that aren't covered by the table PTE. - Fix vPMU issues related to handling of PMUver. - Don't unnecessary align non-stack allocations in the EL2 VA space - Drop HCR_VIRT_EXCP_MASK, which was never used... - Don't use smp_processor_id() in kvm_arch_vcpu_load(), but the cpu parameter instead - Drop redundant call to kvm_set_pfn_accessed() in user_mem_abort() - Remove prototypes without implementations RISC-V: - Zba, Zbs, Zicntr, Zicsr, Zifencei, and Zihpm support for guest - Added ONE_REG interface for SATP mode - Added ONE_REG interface to enable/disable multiple ISA extensions - Improved error codes returned by ONE_REG interfaces - Added KVM_GET_REG_LIST ioctl() implementation for KVM RISC-V - Added get-reg-list selftest for KVM RISC-V s390: - PV crypto passthrough enablement (Tony, Steffen, Viktor, Janosch) Allows a PV guest to use crypto cards. Card access is governed by the firmware and once a crypto queue is "bound" to a PV VM every other entity (PV or not) looses access until it is not bound anymore. Enablement is done via flags when creating the PV VM. - Guest debug fixes (Ilya) x86: - Clean up KVM's handling of Intel architectural events - Intel bugfixes - Add support for SEV-ES DebugSwap, allowing SEV-ES guests to use debug registers and generate/handle #DBs - Clean up LBR virtualization code - Fix a bug where KVM fails to set the target pCPU during an IRTE update - Fix fatal bugs in SEV-ES intrahost migration - Fix a bug where the recent (architecturally correct) change to reinject #BP and skip INT3 broke SEV guests (can't decode INT3 to skip it) - Retry APIC map recalculation if a vCPU is added/enabled - Overhaul emergency reboot code to bring SVM up to par with VMX, tie the "emergency disabling" behavior to KVM actually being loaded, and move all of the logic within KVM - Fix user triggerable WARNs in SVM where KVM incorrectly assumes the TSC ratio MSR cannot diverge from the default when TSC scaling is disabled up related code - Add a framework to allow "caching" feature flags so that KVM can check if the guest can use a feature without needing to search guest CPUID - Rip out the ancient MMU_DEBUG crud and replace the useful bits with CONFIG_KVM_PROVE_MMU - Fix KVM's handling of !visible guest roots to avoid premature triple fault injection - Overhaul KVM's page-track APIs, and KVMGT's usage, to reduce the API surface that is needed by external users (currently only KVMGT), and fix a variety of issues in the process Generic: - Wrap kvm_{gfn,hva}_range.pte in a union to allow mmu_notifier events to pass action specific data without needing to constantly update the main handlers. - Drop unused function declarations Selftests: - Add testcases to x86's sync_regs_test for detecting KVM TOCTOU bugs - Add support for printf() in guest code and covert all guest asserts to use printf-based reporting - Clean up the PMU event filter test and add new testcases - Include x86 selftests in the KVM x86 MAINTAINERS entry" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (279 commits) KVM: x86/mmu: Include mmu.h in spte.h KVM: x86/mmu: Use dummy root, backed by zero page, for !visible guest roots KVM: x86/mmu: Disallow guest from using !visible slots for page tables KVM: x86/mmu: Harden TDP MMU iteration against root w/o shadow page KVM: x86/mmu: Harden new PGD against roots without shadow pages KVM: x86/mmu: Add helper to convert root hpa to shadow page drm/i915/gvt: Drop final dependencies on KVM internal details KVM: x86/mmu: Handle KVM bookkeeping in page-track APIs, not callers KVM: x86/mmu: Drop @slot param from exported/external page-track APIs KVM: x86/mmu: Bug the VM if write-tracking is used but not enabled KVM: x86/mmu: Assert that correct locks are held for page write-tracking KVM: x86/mmu: Rename page-track APIs to reflect the new reality KVM: x86/mmu: Drop infrastructure for multiple page-track modes KVM: x86/mmu: Use page-track notifiers iff there are external users KVM: x86/mmu: Move KVM-only page-track declarations to internal header KVM: x86: Remove the unused page-track hook track_flush_slot() drm/i915/gvt: switch from ->track_flush_slot() to ->track_remove_region() KVM: x86: Add a new page-track hook to handle memslot deletion drm/i915/gvt: Don't bother removing write-protection on to-be-deleted slot KVM: x86: Reject memslot MOVE operations if KVMGT is attached ...