KVM/arm64 changes for 6.17, round #1 - 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.
KVM selftests changes for 6.17 - 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, with a "Root required?" help message. In most cases, the test just needs to be run with elevated permissions.
KVM x86 misc changes for 6.17 - Prevert the host's DEBUGCTL.FREEZE_IN_SMM (Intel only) when running the guest. Failure to honor FREEZE_IN_SMM can bleed host state into the guest. - Explicitly check vmcs12.GUEST_DEBUGCTL on nested VM-Enter (Intel only) to prevent L1 from running L2 with features that KVM doesn't support, e.g. BTF. - Intercept SPEC_CTRL on AMD if the MSR shouldn't exist according to the vCPU's CPUID model. - Rework the MSR interception code so that the SVM and VMX APIs are more or less identical. - Recalculate all MSR intercepts from the "source" on MSR filter changes, and drop the dedicated "shadow" bitmaps (and their awful "max" size defines). - WARN and reject loading kvm-amd.ko instead of panicking the kernel if the nested SVM MSRPM offsets tracker can't handle an MSR. - 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 stuffing INIT_RECEIVED, a.k.a. WFS, and then putting the vCPU into VMX Root Mode (post-VMXON). Use the same approach KVM uses for dealing with "impossible" emulation when running a !URG guest, and simply wait until KVM_RUN to detect that the vCPU has architecturally impossible state. - Add KVM_X86_DISABLE_EXITS_APERFMPERF to allow disabling interception of APERF/MPERF reads, so that a "properly" configured VM can "virtualize" APERF/MPERF (with many caveats). - Reject KVM_SET_TSC_KHZ if vCPUs have been created, as changing the "default" frequency is unsupported for VMs with a "secure" TSC, and there's no known use case for changing the default frequency for other VM types.
Expand kvm_pin_this_task_to_pcpu() into a set of APIs to allow pinning a task (or self) to a CPU (any or specific). This will allow deduplicating code throughout a variety of selftests. Opportunistically use "self" instead of "this_task" as it is both more concise and less ambiguous. Link: https://lore.kernel.org/r/20250626001225.744268-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
Add tests for SError injection considering KVM is more directly involved in delivery: - Pending SErrors are taken at the first CSE after SErrors are unmasked - Pending SErrors aren't taken and remain pending if SErrors are masked - Unmasked SErrors are taken immediately when injected (implementation detail) Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20250708172532.1699409-25-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Add helpers to create eventfds and to (de)assign eventfds via KVM_IRQFD. Tested-by: K Prateek Nayak <kprateek.nayak@amd.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250522235223.3178519-13-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
Add an inner __open_path_or_exit() API to let the caller provide additional information on ENOENT to try and help the user figure out why the test is being skipped, e.g. for files like the page_idle bitmap needed by the access tracking perf, which is dependent on a Kconfig. Immediately convert /dev/kvm to the new API, both as an example and because users might not know that some architectures/setups require loading KVM. Link: https://lore.kernel.org/r/20250516215909.2551628-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
Probe /dev/kvm when getting a KVM module param so that attempting to load a module param super early in a selftest generates a SKIP message about KVM not being loaded/enabled, versus some random parameter not existing. E.g. KVM x86's unconditional retrieval of force_emulation_prefix during kvm_selftest_arch_init() generates a rather confusing error message that takes far too much triage to understand. Link: https://lore.kernel.org/r/20250516215909.2551628-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
KVM selftests changes for 6.16: - Add support for SNP to the various SEV selftests. - Add a selftest to verify fastops instructions via forced emulation. - Add MGLRU support to the access tracking perf test.
KVM/riscv changes for 6.16 - Add vector registers to get-reg-list selftest - VCPU reset related improvements - Remove scounteren initialization from VCPU reset - Support VCPU reset from userspace using set_mpstate() ioctl