KVM (on ARMv8.0) and pKVM (on all revisions of the architecture) uses the split hypervisor model that makes the EL2 code more or less standalone. For this, we totally ignore the VHE mode and stick with the good old v8.0 EL2 setup. This is all good, but means that the EL2 code is limited in what it can do with its own address space. This series proposes to remove this limitation and to allow VHE to be used even with the split hypervisor model. This has some potential isolation benefits[1], and *maybe* allow deviant systems to eventually run pKVM. It introduce a new "mode" for KVM called hVHE, in reference to the nVHE mode, and indicating that only the hypervisor is using VHE. Note that this is all this series does. No effort is made to improve the VA space management, which will be the subject of another series if this one ever makes it. This has been lightly tested on a M1 box, with no measurable change in performance. Thanks, M. [1] https://www.youtube.com/watch?v=1F_Mf2j9eIo&list=PLbzoR-pLrL6qWL3v2KOcvwZ54-w0z5uXV&index=11 Marc Zyngier (17): arm64: Turn kaslr_feature_override into a generic SW feature override arm64: Add KVM_HVHE capability and has_hvhe() predicate arm64: Don't enable VHE for the kernel if OVERRIDE_HVHE is set arm64: Prevent the use of is_kernel_in_hyp_mode() in hypervisor code arm64: Allow EL1 physical timer access when running VHE arm64: Use CPACR_EL1 format to set CPTR_EL2 when E2H is set KVM: arm64: Elide kern_hyp_va() in VHE-specific parts of the hypervisor KVM: arm64: Remove alternatives from sysreg accessors in VHE hypervisor context KVM: arm64: Key use of VHE instructions in nVHE code off ARM64_KVM_HVHE KVM: arm64: Force HCR_EL2.E2H when ARM64_KVM_HVHE is set KVM: arm64: Disable TTBR1_EL2 when using ARM64_KVM_HVHE KVM: arm64: Adjust EL2 stage-1 leaf AP bits when ARM64_KVM_HVHE is set KVM: arm64: Rework CPTR_EL2 programming for HVHE configuration KVM: arm64: Program the timer traps with VHE layout in hVHE mode KVM: arm64: Force HCR_E2H in guest context when ARM64_KVM_HVHE is set arm64: Allow arm64_sw.hvhe on command line KVM: arm64: Terrible timer hack for M1 with hVHE arch/arm64/include/asm/arch_timer.h | 8 ++++ arch/arm64/include/asm/cpufeature.h | 5 +++ arch/arm64/include/asm/el2_setup.h | 16 +++++++- arch/arm64/include/asm/kvm_arm.h | 3 -- arch/arm64/include/asm/kvm_asm.h | 1 + arch/arm64/include/asm/kvm_emulate.h | 33 +++++++++++++++- arch/arm64/include/asm/kvm_hyp.h | 37 +++++++++++++----- arch/arm64/include/asm/kvm_mmu.h | 4 ++ arch/arm64/include/asm/virt.h | 15 +++++++- arch/arm64/kernel/cpufeature.c | 17 +++++++++ arch/arm64/kernel/hyp-stub.S | 21 ++++++++++- arch/arm64/kernel/idreg-override.c | 25 ++++++++----- arch/arm64/kernel/image-vars.h | 3 ++ arch/arm64/kernel/kaslr.c | 6 +-- arch/arm64/kvm/arch_timer.c | 5 +++ arch/arm64/kvm/arm.c | 12 +++++- arch/arm64/kvm/fpsimd.c | 4 +- arch/arm64/kvm/hyp/include/hyp/switch.h | 2 +- arch/arm64/kvm/hyp/nvhe/hyp-main.c | 17 ++++++++- arch/arm64/kvm/hyp/nvhe/pkvm.c | 27 ++++++++++--- arch/arm64/kvm/hyp/nvhe/switch.c | 28 ++++++++------ arch/arm64/kvm/hyp/nvhe/timer-sr.c | 29 ++++++++++---- arch/arm64/kvm/hyp/pgtable.c | 6 ++- arch/arm64/kvm/hyp/vhe/switch.c | 2 +- arch/arm64/tools/cpucaps | 1 + drivers/irqchip/irq-apple-aic.c | 50 ++++++++++++++++++++++++- 26 files changed, 312 insertions(+), 65 deletions(-) -- 2.34.1
