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

[Ley Foon Tan]

On Mon, Oct 4, 2021 at 12:47 PM Anup Patel <anup at brainfault.org> wrote:
>
> On Mon, Oct 4, 2021 at 7:58 AM Ley Foon Tan <lftan.linux at gmail.com> wrote:
> >
> > On Fri, Oct 1, 2021 at 6:41 PM Anup Patel <anup at brainfault.org> wrote:
> > >
> > > On Fri, Oct 1, 2021 at 2:33 PM Ley Foon Tan <lftan.linux at gmail.com> wrote:
> > > >
> > > > On Mon, Sep 27, 2021 at 8:01 PM Anup Patel <anup at brainfault.org> wrote:
> > > > >
> > > > > Hi Palmer, Hi Paolo,
> > > > >
> > > > > On Mon, Sep 27, 2021 at 5:10 PM Anup Patel <anup.patel at wdc.com> 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 .....
> > > > > >
> > > > > > This series can be found in riscv_kvm_v20 branch at:
> > > > > > https//github.com/avpatel/linux.git
> > > > > >
> > > > > > Our work-in-progress KVMTOOL RISC-V port can be found in riscv_v9 branch
> > > > > > at: https//github.com/avpatel/kvmtool.git
> > > > > >
> > > > > > The QEMU RISC-V hypervisor emulation is done by Alistair and is available
> > > > > > in master branch at: https://git.qemu.org/git/qemu.git
> > > > > >
> > > > > > To play around with KVM RISC-V, refer KVM RISC-V wiki at:
> > > > > > https://github.com/kvm-riscv/howto/wiki
> > > > > > https://github.com/kvm-riscv/howto/wiki/KVM-RISCV64-on-QEMU
> > > > > > https://github.com/kvm-riscv/howto/wiki/KVM-RISCV64-on-Spike
> > > > > >
>
> <snip>
>
> > Hi Anup
> >
> > It is able to boot up to kvm guest OS after change to use
> > https://github.com/avpatel/qemu.git, riscv_aia_v2 branch.
> > Is there dependency to AIA hardware feature for KVM?
>
> No, there is no dependency on AIA hardware and KVM RISC-V
> v20 series.
>
> I quickly tried the latest QEMU master with KVM RISC-V v20 and
> it worked perfectly fine for me.
> (QEMU master commit 30bd1db58b09c12b68c35f041f919014b885482d)
My last pull on master was last Thursday, last commit is
0021c4765a6b83e5b09409b75d50c6caaa6971b9.
After git pull again today (commit
30bd1db58b09c12b68c35f041f919014b885482d), it can boot KVM on Qemu
now.

>
> Although, I did see that VS-mode interrupts were broken in the latest
> Spike due to some recent merge. I have sent fix PR to Spike for this.
> (Refer, https://github.com/riscv-software-src/riscv-isa-sim/pull/822)
>
> With Spike fix PR (above), the KVM RISC-V v20 series works fine
> on Spike as well.
KVM bootup successfully on Spike with this fix.

Thanks.

Regards
Ley Foon