Re: [PATCH v5 00/13] Add riscv kvm accel support

[Alistair Francis <alistair23@gmail.com>]

On Wed, Jan 12, 2022 at 6:20 PM Yifei Jiang via <qemu-devel@nongnu.org> wrote:
>
> This series adds both riscv32 and riscv64 kvm support, and implements
> migration based on riscv.
>
> Because of RISC-V KVM has been merged into the Linux master, so this
> series are changed from RFC to patch.
>
> Several steps to use this:
> 1. Build emulation
> $ ./configure --target-list=riscv64-softmmu
> $ make -j$(nproc)
>
> 2. Build kernel
>
> 3. Build QEMU VM
> Cross built in riscv toolchain.
> $ PKG_CONFIG_LIBDIR=<toolchain pkgconfig path>
> $ export PKG_CONFIG_SYSROOT_DIR=<toolchain sysroot path>
> $ ./configure --target-list=riscv64-softmmu --enable-kvm \
> --cross-prefix=riscv64-linux-gnu- --disable-libiscsi --disable-glusterfs \
> --disable-libusb --disable-usb-redir --audio-drv-list= --disable-opengl \
> --disable-libxml2
> $ make -j$(nproc)
>
> 4. Start emulation
> $ ./qemu-system-riscv64 -M virt -m 4096M -cpu rv64 -nographic \
>         -name guest=riscv-hyp,debug-threads=on \
>         -smp 4 \
>         -bios ./fw_jump.bin \
>         -kernel ./Image \
>         -drive file=./hyp.img,format=raw,id=hd0 \
>         -device virtio-blk-device,drive=hd0 \
>         -append "root=/dev/vda rw console=ttyS0 earlycon=sbi"
>
> 5. Start kvm-acceled QEMU VM in emulation
> $ ./qemu-system-riscv64 -M virt,accel=kvm -m 1024M -cpu host -nographic \
>         -name guest=riscv-guset \
>         -smp 2 \
>         -bios none \
>         -kernel ./Image \
>         -drive file=./guest.img,format=raw,id=hd0 \
>         -device virtio-blk-device,drive=hd0 \
>         -append "root=/dev/vda rw console=ttyS0 earlycon=sbi"
>
> Changes since patch v4
> - Commit enable kvm accel as an independent patch.
> - Bugfix some checkpatch errors.
> - Bugfix lost a interrupt in the sifive_u machine.
>
> Changes since patch v3
> - Re-write the for-loop in sifive_plic_create().
> - Drop unnecessary change in hw/riscv/virt.c.
> - Use serial to handle console sbi call.
>
> Changes since patch v2
> - Create a macro for get and put timer csr.
> - Remove M-mode PLIC contexts when kvm is enabled.
> - Add get timer frequency.
> - Move cpu_host_load to vmstate_kvmtimer.
>
> Changes since patch v1
> - Rebase on recent commit a216e7cf119c91ffdf5931834a1a030ebea40d70
> - Sync-up headers with Linux-5.16-rc4.
> - Fixbug in kvm_arch_init_vcpu.
> - Create a macro for get and put regs csr.
> - Start kernel directly when kvm_enabled.
> - Use riscv_cpu_set_irq to inject KVM interrupts.
> - Use the Semihosting Console API for RISC-V kvm handle sbi.
> - Update vmstate_riscv_cpu version id.
>   Placing kvm_timer into a subsection.
>
> Changes since RFC v6
> - Rebase on recent commit 8627edfb3f1fca24a96a0954148885c3241c10f8
> - Sync-up headers with Linux-5.16-rc1
>
> Changes since RFC v5
> - Rebase on QEMU v6.1.0-rc1 and kvm-riscv linux v19.
> - Move kvm interrupt setting to riscv_cpu_update_mip().
> - Replace __u64 with uint64_t.
>
> Changes since RFC v4
> - Rebase on QEMU v6.0.0-rc2 and kvm-riscv linux v17.
> - Remove time scaling support as software solution is incomplete.
>   Because it will cause unacceptable performance degradation. and
>   We will post a better solution.
> - Revise according to Alistair's review comments.
>   - Remove compile time XLEN checks in kvm_riscv_reg_id
>   - Surround TYPE_RISCV_CPU_HOST definition by CONFIG_KVM and share
>     it between RV32 and RV64.
>   - Add kvm-stub.c for reduce unnecessary compilation checks.
>   - Add riscv_setup_direct_kernel() to direct boot kernel for KVM.
>
> Changes since RFC v3
> - Rebase on QEMU v5.2.0-rc2 and kvm-riscv linux v15.
> - Add time scaling support(New patches 13, 14 and 15).
> - Fix the bug that guest vm can't reboot.
>
> Changes since RFC v2
> - Fix checkpatch error at target/riscv/sbi_ecall_interface.h.
> - Add riscv migration support.
>
> Changes since RFC v1
> - Add separate SBI ecall interface header.
> - Add riscv32 kvm accel support.
>
> Yifei Jiang (13):
>   update-linux-headers: Add asm-riscv/kvm.h
>   target/riscv: Add target/riscv/kvm.c to place the public kvm interface
>   target/riscv: Implement function kvm_arch_init_vcpu
>   target/riscv: Implement kvm_arch_get_registers
>   target/riscv: Implement kvm_arch_put_registers
>   target/riscv: Support start kernel directly by KVM
>   target/riscv: Support setting external interrupt by KVM
>   target/riscv: Handle KVM_EXIT_RISCV_SBI exit
>   target/riscv: Add host cpu type
>   target/riscv: Add kvm_riscv_get/put_regs_timer
>   target/riscv: Implement virtual time adjusting with vm state changing
>   target/riscv: Support virtual time context synchronization
>   target/riscv: enable riscv kvm accel

Thanks!

Applied to riscv-to-apply.next

Alistair

>
>  hw/intc/sifive_plic.c              |  20 +-
>  hw/riscv/boot.c                    |  16 +-
>  hw/riscv/virt.c                    |  83 +++--
>  include/hw/riscv/boot.h            |   1 +
>  linux-headers/asm-riscv/kvm.h      | 128 +++++++
>  meson.build                        |   2 +
>  target/riscv/cpu.c                 |  29 +-
>  target/riscv/cpu.h                 |  11 +
>  target/riscv/kvm-stub.c            |  30 ++
>  target/riscv/kvm.c                 | 535 +++++++++++++++++++++++++++++
>  target/riscv/kvm_riscv.h           |  25 ++
>  target/riscv/machine.c             |  30 ++
>  target/riscv/meson.build           |   1 +
>  target/riscv/sbi_ecall_interface.h |  72 ++++
>  14 files changed, 951 insertions(+), 32 deletions(-)
>  create mode 100644 linux-headers/asm-riscv/kvm.h
>  create mode 100644 target/riscv/kvm-stub.c
>  create mode 100644 target/riscv/kvm.c
>  create mode 100644 target/riscv/kvm_riscv.h
>  create mode 100644 target/riscv/sbi_ecall_interface.h
>
> --
> 2.19.1
>
>