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

Pull kvm updates from Paolo Bonzini:
 "ARM:

   - Host driver for GICv5, the next generation interrupt controller for
     arm64, including support for interrupt routing, MSIs, interrupt
     translation and wired interrupts

   - Use FEAT_GCIE_LEGACY on GICv5 systems to virtualize GICv3 VMs on
     GICv5 hardware, leveraging the legacy VGIC interface

   - Userspace control of the 'nASSGIcap' GICv3 feature, allowing
     userspace to disable support for SGIs w/o an active state on
     hardware that previously advertised it unconditionally

   - Map supporting endpoints with cacheable memory attributes on
     systems with FEAT_S2FWB and DIC where KVM no longer needs to
     perform cache maintenance on the address range

   - Nested support for FEAT_RAS and FEAT_DoubleFault2, allowing the
     guest hypervisor to inject external aborts into an L2 VM and take
     traps of masked external aborts to the hypervisor

   - Convert more system register sanitization to the config-driven
     implementation

   - Fixes to the visibility of EL2 registers, namely making VGICv3
     system registers accessible through the VGIC device instead of the
     ONE_REG vCPU ioctls

   - Various cleanups and minor fixes

  LoongArch:

   - Add stat information for in-kernel irqchip

   - Add tracepoints for CPUCFG and CSR emulation exits

   - Enhance in-kernel irqchip emulation

   - Various cleanups

  RISC-V:

   - Enable ring-based dirty memory tracking

   - Improve perf kvm stat to report interrupt events

   - Delegate illegal instruction trap to VS-mode

   - MMU improvements related to upcoming nested virtualization

  s390x

   - Fixes

  x86:

   - Add CONFIG_KVM_IOAPIC for x86 to allow disabling support for I/O
     APIC, PIC, and PIT emulation at compile time

   - Share device posted IRQ code between SVM and VMX and harden it
     against bugs and runtime errors

   - Use vcpu_idx, not vcpu_id, for GA log tag/metadata, to make lookups
     O(1) instead of O(n)

   - For MMIO stale data mitigation, track whether or not a vCPU has
     access to (host) MMIO based on whether the page tables have MMIO
     pfns mapped; using VFIO is prone to false negatives

   - Rework the MSR interception code so that the SVM and VMX APIs are
     more or less identical

   - Recalculate all MSR intercepts from scratch on MSR filter changes,
     instead of maintaining shadow bitmaps

   - Advertise support for LKGS (Load Kernel GS base), a new instruction
     that's loosely related to FRED, but is supported and enumerated
     independently

   - Fix a user-triggerable WARN that syzkaller found by setting the
     vCPU in INIT_RECEIVED state (aka wait-for-SIPI), and then putting
     the vCPU into VMX Root Mode (post-VMXON). Trying to detect every
     possible path leading to architecturally forbidden states is hard
     and even risks breaking userspace (if it goes from valid to valid
     state but passes through invalid states), so just wait until
     KVM_RUN to detect that the vCPU state isn't allowed

   - Add KVM_X86_DISABLE_EXITS_APERFMPERF to allow disabling
     interception of APERF/MPERF reads, so that a "properly" configured
     VM can access APERF/MPERF. This has many caveats (APERF/MPERF
     cannot be zeroed on vCPU creation or saved/restored on suspend and
     resume, or preserved over thread migration let alone VM migration)
     but can be useful whenever you're interested in letting Linux
     guests see the effective physical CPU frequency in /proc/cpuinfo

   - Reject KVM_SET_TSC_KHZ for vm file descriptors if vCPUs have been
     created, as there's no known use case for changing the default
     frequency for other VM types and it goes counter to the very reason
     why the ioctl was added to the vm file descriptor. And also, there
     would be no way to make it work for confidential VMs with a
     "secure" TSC, so kill two birds with one stone

   - Dynamically allocation the shadow MMU's hashed page list, and defer
     allocating the hashed list until it's actually needed (the TDP MMU
     doesn't use the list)

   - Extract many of KVM's helpers for accessing architectural local
     APIC state to common x86 so that they can be shared by guest-side
     code for Secure AVIC

   - Various cleanups and fixes

  x86 (Intel):

   - Preserve the host's DEBUGCTL.FREEZE_IN_SMM when running the guest.
     Failure to honor FREEZE_IN_SMM can leak host state into guests

   - Explicitly check vmcs12.GUEST_DEBUGCTL on nested VM-Enter to
     prevent L1 from running L2 with features that KVM doesn't support,
     e.g. BTF

  x86 (AMD):

   - WARN and reject loading kvm-amd.ko instead of panicking the kernel
     if the nested SVM MSRPM offsets tracker can't handle an MSR (which
     is pretty much a static condition and therefore should never
     happen, but still)

   - Fix a variety of flaws and bugs in the AVIC device posted IRQ code

   - Inhibit AVIC if a vCPU's ID is too big (relative to what hardware
     supports) instead of rejecting vCPU creation

   - Extend enable_ipiv module param support to SVM, by simply leaving
     IsRunning clear in the vCPU's physical ID table entry

   - Disable IPI virtualization, via enable_ipiv, if the CPU is affected
     by erratum #1235, to allow (safely) enabling AVIC on such CPUs

   - Request GA Log interrupts if and only if the target vCPU is
     blocking, i.e. only if KVM needs a notification in order to wake
     the vCPU

   - Intercept SPEC_CTRL on AMD if the MSR shouldn't exist according to
     the vCPU's CPUID model

   - Accept any SNP policy that is accepted by the firmware with respect
     to SMT and single-socket restrictions. An incompatible policy
     doesn't put the kernel at risk in any way, so there's no reason for
     KVM to care

   - Drop a superfluous WBINVD (on all CPUs!) when destroying a VM and
     use WBNOINVD instead of WBINVD when possible for SEV cache
     maintenance

   - When reclaiming memory from an SEV guest, only do cache flushes on
     CPUs that have ever run a vCPU for the guest, i.e. don't flush the
     caches for CPUs that can't possibly have cache lines with dirty,
     encrypted data

  Generic:

   - Rework irqbypass to track/match producers and consumers via an
     xarray instead of a linked list. Using a linked list leads to
     O(n^2) insertion times, which is hugely problematic for use cases
     that create large numbers of VMs. Such use cases typically don't
     actually use irqbypass, but eliminating the pointless registration
     is a future problem to solve as it likely requires new uAPI

   - Track irqbypass's "token" as "struct eventfd_ctx *" instead of a
     "void *", to avoid making a simple concept unnecessarily difficult
     to understand

   - Decouple device posted IRQs from VFIO device assignment, as binding
     a VM to a VFIO group is not a requirement for enabling device
     posted IRQs

   - Clean up and document/comment the irqfd assignment code

   - Disallow binding multiple irqfds to an eventfd with a priority
     waiter, i.e. ensure an eventfd is bound to at most one irqfd
     through the entire host, and add a selftest to verify eventfd:irqfd
     bindings are globally unique

   - Add a tracepoint for KVM_SET_MEMORY_ATTRIBUTES to help debug issues
     related to private <=> shared memory conversions

   - Drop guest_memfd's .getattr() implementation as the VFS layer will
     call generic_fillattr() if inode_operations.getattr is NULL

   - Fix issues with dirty ring harvesting where KVM doesn't bound the
     processing of entries in any way, which allows userspace to keep
     KVM in a tight loop indefinitely

   - Kill off kvm_arch_{start,end}_assignment() and x86's associated
     tracking, now that KVM no longer uses assigned_device_count as a
     heuristic for either irqbypass usage or MDS mitigation

  Selftests:

   - Fix a comment typo

   - Verify KVM is loaded when getting any KVM module param so that
     attempting to run a selftest without kvm.ko loaded results in a
     SKIP message about KVM not being loaded/enabled (versus some random
     parameter not existing)

   - Skip tests that hit EACCES when attempting to access a file, and
     print a "Root required?" help message. In most cases, the test just
     needs to be run with elevated permissions"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (340 commits)
  Documentation: KVM: Use unordered list for pre-init VGIC registers
  RISC-V: KVM: Avoid re-acquiring memslot in kvm_riscv_gstage_map()
  RISC-V: KVM: Use find_vma_intersection() to search for intersecting VMAs
  RISC-V: perf/kvm: Add reporting of interrupt events
  RISC-V: KVM: Enable ring-based dirty memory tracking
  RISC-V: KVM: Fix inclusion of Smnpm in the guest ISA bitmap
  RISC-V: KVM: Delegate illegal instruction fault to VS mode
  RISC-V: KVM: Pass VMID as parameter to kvm_riscv_hfence_xyz() APIs
  RISC-V: KVM: Factor-out g-stage page table management
  RISC-V: KVM: Add vmid field to struct kvm_riscv_hfence
  RISC-V: KVM: Introduce struct kvm_gstage_mapping
  RISC-V: KVM: Factor-out MMU related declarations into separate headers
  RISC-V: KVM: Use ncsr_xyz() in kvm_riscv_vcpu_trap_redirect()
  RISC-V: KVM: Implement kvm_arch_flush_remote_tlbs_range()
  RISC-V: KVM: Don't flush TLB when PTE is unchanged
  RISC-V: KVM: Replace KVM_REQ_HFENCE_GVMA_VMID_ALL with KVM_REQ_TLB_FLUSH
  RISC-V: KVM: Rename and move kvm_riscv_local_tlb_sanitize()
  RISC-V: KVM: Drop the return value of kvm_riscv_vcpu_aia_init()
  RISC-V: KVM: Check kvm_riscv_vcpu_alloc_vector_context() return value
  KVM: arm64: selftests: Add FEAT_RAS EL2 registers to get-reg-list
  ...