[PATCH v20 00/17] KVM RISC-V Support

[Anup Patel]

On Mon, Oct 4, 2021 at 11:31 PM Palmer Dabbelt <palmerdabbelt at google.com> wrote:
>
> On Mon, 04 Oct 2021 01:58:28 PDT (-0700), pbonzini at redhat.com wrote:
> > On 27/09/21 13:39, Anup Patel wrote:
> >> This series adds initial KVM RISC-V support. Currently, we are able to boot
> >> Linux on RV64/RV32 Guest with multiple VCPUs.
> >>
> >> Key aspects of KVM RISC-V added by this series are:
> >> 1. No RISC-V specific KVM IOCTL
> >> 2. Loadable KVM RISC-V module supported
> >> 3. Minimal possible KVM world-switch which touches only GPRs and few CSRs
> >> 4. Both RV64 and RV32 host supported
> >> 5. Full Guest/VM switch is done via vcpu_get/vcpu_put infrastructure
> >> 6. KVM ONE_REG interface for VCPU register access from user-space
> >> 7. PLIC emulation is done in user-space
> >> 8. Timer and IPI emuation is done in-kernel
> >> 9. Both Sv39x4 and Sv48x4 supported for RV64 host
> >> 10. MMU notifiers supported
> >> 11. Generic dirtylog supported
> >> 12. FP lazy save/restore supported
> >> 13. SBI v0.1 emulation for KVM Guest available
> >> 14. Forward unhandled SBI calls to KVM userspace
> >> 15. Hugepage support for Guest/VM
> >> 16. IOEVENTFD support for Vhost
> >>
> >> Here's a brief TODO list which we will work upon after this series:
> >> 1. KVM unit test support
> >> 2. KVM selftest support
> >> 3. SBI v0.3 emulation in-kernel
> >> 4. In-kernel PMU virtualization
> >> 5. In-kernel AIA irqchip support
> >> 6. Nested virtualizaiton
> >> 7. ..... and more .....
> >
> > Looks good, I prepared a tag "for-riscv" at
> > https://git.kernel.org/pub/scm/virt/kvm/kvm.git.  Palmer can pull it and
> > you can use it to send me a pull request.
>
> Thanks.  I'm assuming "you" there is Anup?
>
> Just to make sure we're on the same page here, I've got
>
>     commit 6c341a285912ddb2894ef793a58ad4f8462f26f4 (HEAD -> for-next)
>     Merge: 08da1608a1ca 3f2401f47d29
>     Author: Palmer Dabbelt <palmerdabbelt at google.com>
>     Date:   Mon Oct 4 10:12:44 2021 -0700
>
>         Merge tag 'for-riscv' of https://git.kernel.org/pub/scm/virt/kvm/kvm.git into for-next
>
>         H extension definitions, shared by the KVM and RISC-V trees.
>
>         * tag 'for-riscv' of ssh://gitolite.kernel.org/pub/scm/virt/kvm/kvm: (301 commits)
>           RISC-V: Add hypervisor extension related CSR defines
>           KVM: selftests: Ensure all migrations are performed when test is affined
>           KVM: x86: Swap order of CPUID entry "index" vs. "significant flag" checks
>           ptp: Fix ptp_kvm_getcrosststamp issue for x86 ptp_kvm
>           x86/kvmclock: Move this_cpu_pvti into kvmclock.h
>           KVM: s390: Function documentation fixes
>           selftests: KVM: Don't clobber XMM register when read
>           KVM: VMX: Fix a TSX_CTRL_CPUID_CLEAR field mask issue
>           selftests: KVM: Explicitly use movq to read xmm registers
>           selftests: KVM: Call ucall_init when setting up in rseq_test
>           KVM: Remove tlbs_dirty
>           KVM: X86: Synchronize the shadow pagetable before link it
>           KVM: X86: Fix missed remote tlb flush in rmap_write_protect()
>           KVM: x86: nSVM: don't copy virt_ext from vmcb12
>           KVM: x86: nSVM: test eax for 4K alignment for GP errata workaround
>           KVM: x86: selftests: test simultaneous uses of V_IRQ from L1 and L0
>           KVM: x86: nSVM: restore int_vector in svm_clear_vintr
>           kvm: x86: Add AMD PMU MSRs to msrs_to_save_all[]
>           KVM: x86: nVMX: re-evaluate emulation_required on nested VM exit
>           KVM: x86: nVMX: don't fail nested VM entry on invalid guest state if !from_vmentry
>           ...
>
> into ssh://git@gitolite.kernel.org/pub/scm/linux/kernel/git/palmer/linux.git for-next
> (I know that's kind of a confusing name, but it's what I've been using
> as my short-term staging branch so I can do all my tests before saying
> "it's on for-next").
>
> If that looks OK I can make it a touch more official by putting into the
> RISC-V tree.
>
> > I look forward to the test support. :)  Would be nice to have selftest
> > support already in 5.16, since there are a few arch-independent
> > selftests that cover the hairy parts of the MMU.
>
> Me too ;).
>
> I'm happy to add some KVM-related stuff to my pre-push test set, just
> LMK if there's anything specific I should be looking in to.

Thanks Palmer, I will ping you once I have basic kvm-selftest patches
ready for RISC-V.

Regards,
Anup