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

[Guo Ren]

On Tue, Oct 5, 2021 at 1:46 AM Atish Patra <atishp at atishpatra.org> wrote:
>
> On Mon, Oct 4, 2021 at 9:15 AM Guo Ren <guoren at kernel.org> wrote:
> >
> > Tested-by: Guo Ren <guoren at kernel.org>
> >
> > qemu: commit 8880cc4362fde4ecdac0b2092318893118206fcf (HEAD -> master,
> > qemu/master)
> > kvmtool: commit 31627784e671d86fcc6f4754888b03dc83d3ec4a (HEAD ->
> > riscv_v9, avpatel/riscv_v9)
> > linux: commit 3940bf8c7e029e86beb82817708bc9c2c8781379 (HEAD ->
> > riscv_kvm_v20, avpatel/riscv_kvm_v20)
> > opensbi: commit 754d51192b6bf6a4afd9d46c5f736a9f6dd1b404 (HEAD ->
> > master, origin/master, origin/HEAD)
> >
> > Find a small issue:
> >
> > [    4.743119] Freeing unused kernel image (initmem) memory: 2144K
> > [    4.778912] Run /virt/init as init process
> > Mounting...
> > [    5.276235] random: fast init done
> > / # poweroff
> > / #
> >   # KVM session ended normally.
> > Using ctrl + a, ctrl + a, x could exit, but poweroff has no effect.
>
> You probably don't have the follow up kvm patch series that adds SRST
> support in kvm
> https://patchwork.kernel.org/project/kvm/patch/20210204053239.1609558-7-atish.patra@wdc.com/
Yes, and thx for the explanation.

>
> FYI: I will rebase the entire series and send it once the base kvm
> series is available online.
>
> >
> > On Mon, Sep 27, 2021 at 7:40 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
> > >
> > > Changes since v19:
> > >  - Rebased on Linux-5.15-rc3
> > >  - Converted kvm_err() to kvm_debug() in kvm_set_spte_gfn() function
> > >    added by PATCH11
> > >
> > > Changes since v18:
> > >  - Rebased on Linux-5.14-rc3
> > >  - Moved to new KVM debugfs interface
> > >  - Dropped PATCH17 of v18 series for having KVM RISC-V in drivers/staging
> > >
> > > Changes since v17:
> > >  - Rebased on Linux-5.13-rc2
> > >  - Moved to new KVM MMU notifier APIs
> > >  - Removed redundant kvm_arch_vcpu_uninit()
> > >  - Moved KVM RISC-V sources to drivers/staging for compliance with
> > >    Linux RISC-V patch acceptance policy
> > >
> > > Changes since v16:
> > >  - Rebased on Linux-5.12-rc5
> > >  - Remove redundant kvm_arch_create_memslot(), kvm_arch_vcpu_setup(),
> > >    kvm_arch_vcpu_init(), kvm_arch_has_vcpu_debugfs(), and
> > >    kvm_arch_create_vcpu_debugfs() from PATCH5
> > >  - Make stage2_wp_memory_region() and stage2_ioremap() as static
> > >    in PATCH13
> > >
> > > Changes since v15:
> > >  - Rebased on Linux-5.11-rc3
> > >  - Fixed kvm_stage2_map() to use gfn_to_pfn_prot() for determing
> > >    writeability of a host pfn.
> > >  - Use "__u64" in-place of "u64" and "__u32" in-place of "u32" for
> > >    uapi/asm/kvm.h
> > >
> > > Changes since v14:
> > >  - Rebased on Linux-5.10-rc3
> > >  - Fixed Stage2 (G-stage) PDG allocation to ensure it is 16KB aligned
> > >
> > > Changes since v13:
> > >  - Rebased on Linux-5.9-rc3
> > >  - Fixed kvm_riscv_vcpu_set_reg_csr() for SIP updation in PATCH5
> > >  - Fixed instruction length computation in PATCH7
> > >  - Added ioeventfd support in PATCH7
> > >  - Ensure HSTATUS.SPVP is set to correct value before using HLV/HSV
> > >    intructions in PATCH7
> > >  - Fixed stage2_map_page() to set PTE 'A' and 'D' bits correctly
> > >    in PATCH10
> > >  - Added stage2 dirty page logging in PATCH10
> > >  - Allow KVM user-space to SET/GET SCOUNTER CSR in PATCH5
> > >  - Save/restore SCOUNTEREN in PATCH6
> > >  - Reduced quite a few instructions for __kvm_riscv_switch_to() by
> > >    using CSR swap instruction in PATCH6
> > >  - Detect and use Sv48x4 when available in PATCH10
> > >
> > > Changes since v12:
> > >  - Rebased patches on Linux-5.8-rc4
> > >  - By default enable all counters in HCOUNTEREN
> > >  - RISC-V H-Extension v0.6.1 spec support
> > >
> > > Changes since v11:
> > >  - Rebased patches on Linux-5.7-rc3
> > >  - Fixed typo in typecast of stage2_map_size define
> > >  - Introduced struct kvm_cpu_trap to represent trap details and
> > >    use it as function parameter wherever applicable
> > >  - Pass memslot to kvm_riscv_stage2_map() for supporing dirty page
> > >    logging in future
> > >  - RISC-V H-Extension v0.6 spec support
> > >  - Send-out first three patches as separate series so that it can
> > >    be taken by Palmer for Linux RISC-V
> > >
> > > Changes since v10:
> > >  - Rebased patches on Linux-5.6-rc5
> > >  - Reduce RISCV_ISA_EXT_MAX from 256 to 64
> > >  - Separate PATCH for removing N-extension related defines
> > >  - Added comments as requested by Palmer
> > >  - Fixed HIDELEG CSR programming
> > >
> > > Changes since v9:
> > >  - Rebased patches on Linux-5.5-rc3
> > >  - Squash PATCH19 and PATCH20 into PATCH5
> > >  - Squash PATCH18 into PATCH11
> > >  - Squash PATCH17 into PATCH16
> > >  - Added ONE_REG interface for VCPU timer in PATCH13
> > >  - Use HTIMEDELTA for VCPU timer in PATCH13
> > >  - Updated KVM RISC-V mailing list in MAINTAINERS entry
> > >  - Update KVM kconfig option to depend on RISCV_SBI and MMU
> > >  - Check for SBI v0.2 and SBI v0.2 RFENCE extension at boot-time
> > >  - Use SBI v0.2 RFENCE extension in VMID implementation
> > >  - Use SBI v0.2 RFENCE extension in Stage2 MMU implementation
> > >  - Use SBI v0.2 RFENCE extension in SBI implementation
> > >  - Moved to RISC-V Hypervisor v0.5 draft spec
> > >  - Updated Documentation/virt/kvm/api.txt for timer ONE_REG interface
> > >
> > > Changes since v8:
> > >  - Rebased series on Linux-5.4-rc3 and Atish's SBI v0.2 patches
> > >  - Use HRTIMER_MODE_REL instead of HRTIMER_MODE_ABS in timer emulation
> > >  - Fixed kvm_riscv_stage2_map() to handle hugepages
> > >  - Added patch to forward unhandled SBI calls to user-space
> > >  - Added patch for iterative/recursive stage2 page table programming
> > >  - Added patch to remove per-CPU vsip_shadow variable
> > >  - Added patch to fix race-condition in kvm_riscv_vcpu_sync_interrupts()
> > >
> > > Changes since v7:
> > >  - Rebased series on Linux-5.4-rc1 and Atish's SBI v0.2 patches
> > >  - Removed PATCH1, PATCH3, and PATCH20 because these already merged
> > >  - Use kernel doc style comments for ISA bitmap functions
> > >  - Don't parse X, Y, and Z extension in riscv_fill_hwcap() because it will
> > >    be added in-future
> > >  - Mark KVM RISC-V kconfig option as EXPERIMENTAL
> > >  - Typo fix in commit description of PATCH6 of v7 series
> > >  - Use separate structs for CORE and CSR registers of ONE_REG interface
> > >  - Explicitly include asm/sbi.h in kvm/vcpu_sbi.c
> > >  - Removed implicit switch-case fall-through in kvm_riscv_vcpu_exit()
> > >  - No need to set VSSTATUS.MXR bit in kvm_riscv_vcpu_unpriv_read()
> > >  - Removed register for instruction length in kvm_riscv_vcpu_unpriv_read()
> > >  - Added defines for checking/decoding instruction length
> > >  - Added separate patch to forward unhandled SBI calls to userspace tool
> > >
> > > Changes since v6:
> > >  - Rebased patches on Linux-5.3-rc7
> > >  - Added "return_handled" in struct kvm_mmio_decode to ensure that
> > >    kvm_riscv_vcpu_mmio_return() updates SEPC only once
> > >  - Removed trap_stval parameter from kvm_riscv_vcpu_unpriv_read()
> > >  - Updated git repo URL in MAINTAINERS entry
> > >
> > > Changes since v5:
> > >  - Renamed KVM_REG_RISCV_CONFIG_TIMEBASE register to
> > >    KVM_REG_RISCV_CONFIG_TBFREQ register in ONE_REG interface
> > >  - Update SPEC in kvm_riscv_vcpu_mmio_return() for MMIO exits
> > >  - Use switch case instead of illegal instruction opcode table for simplicity
> > >  - Improve comments in stage2_remote_tlb_flush() for a potential remote TLB
> > >   flush optimization
> > >  - Handle all unsupported SBI calls in default case of
> > >    kvm_riscv_vcpu_sbi_ecall() function
> > >  - Fixed kvm_riscv_vcpu_sync_interrupts() for software interrupts
> > >  - Improved unprivilege reads to handle traps due to Guest stage1 page table
> > >  - Added separate patch to document RISC-V specific things in
> > >    Documentation/virt/kvm/api.txt
> > >
> > > Changes since v4:
> > >  - Rebased patches on Linux-5.3-rc5
> > >  - Added Paolo's Acked-by and Reviewed-by
> > >  - Updated mailing list in MAINTAINERS entry
> > >
> > > Changes since v3:
> > >  - Moved patch for ISA bitmap from KVM prep series to this series
> > >  - Make vsip_shadow as run-time percpu variable instead of compile-time
> > >  - Flush Guest TLBs on all Host CPUs whenever we run-out of VMIDs
> > >
> > > Changes since v2:
> > >  - Removed references of KVM_REQ_IRQ_PENDING from all patches
> > >  - Use kvm->srcu within in-kernel KVM run loop
> > >  - Added percpu vsip_shadow to track last value programmed in VSIP CSR
> > >  - Added comments about irqs_pending and irqs_pending_mask
> > >  - Used kvm_arch_vcpu_runnable() in-place-of kvm_riscv_vcpu_has_interrupt()
> > >    in system_opcode_insn()
> > >  - Removed unwanted smp_wmb() in kvm_riscv_stage2_vmid_update()
> > >  - Use kvm_flush_remote_tlbs() in kvm_riscv_stage2_vmid_update()
> > >  - Use READ_ONCE() in kvm_riscv_stage2_update_hgatp() for vmid
> > >
> > > Changes since v1:
> > >  - Fixed compile errors in building KVM RISC-V as module
> > >  - Removed unused kvm_riscv_halt_guest() and kvm_riscv_resume_guest()
> > >  - Set KVM_CAP_SYNC_MMU capability only after MMU notifiers are implemented
> > >  - Made vmid_version as unsigned long instead of atomic
> > >  - Renamed KVM_REQ_UPDATE_PGTBL to KVM_REQ_UPDATE_HGATP
> > >  - Renamed kvm_riscv_stage2_update_pgtbl() to kvm_riscv_stage2_update_hgatp()
> > >  - Configure HIDELEG and HEDELEG in kvm_arch_hardware_enable()
> > >  - Updated ONE_REG interface for CSR access to user-space
> > >  - Removed irqs_pending_lock and use atomic bitops instead
> > >  - Added separate patch for FP ONE_REG interface
> > >  - Added separate patch for updating MAINTAINERS file
> > >
> > > Anup Patel (13):
> > >   RISC-V: Add hypervisor extension related CSR defines
> > >   RISC-V: Add initial skeletal KVM support
> > >   RISC-V: KVM: Implement VCPU create, init and destroy functions
> > >   RISC-V: KVM: Implement VCPU interrupts and requests handling
> > >   RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls
> > >   RISC-V: KVM: Implement VCPU world-switch
> > >   RISC-V: KVM: Handle MMIO exits for VCPU
> > >   RISC-V: KVM: Handle WFI exits for VCPU
> > >   RISC-V: KVM: Implement VMID allocator
> > >   RISC-V: KVM: Implement stage2 page table programming
> > >   RISC-V: KVM: Implement MMU notifiers
> > >   RISC-V: KVM: Document RISC-V specific parts of KVM API
> > >   RISC-V: KVM: Add MAINTAINERS entry
> > >
> > > Atish Patra (4):
> > >   RISC-V: KVM: Add timer functionality
> > >   RISC-V: KVM: FP lazy save/restore
> > >   RISC-V: KVM: Implement ONE REG interface for FP registers
> > >   RISC-V: KVM: Add SBI v0.1 support
> > >
> > >  Documentation/virt/kvm/api.rst          | 193 ++++-
> > >  MAINTAINERS                             |  12 +
> > >  arch/riscv/Kconfig                      |   1 +
> > >  arch/riscv/Makefile                     |   1 +
> > >  arch/riscv/include/asm/csr.h            |  87 +++
> > >  arch/riscv/include/asm/kvm_host.h       | 266 +++++++
> > >  arch/riscv/include/asm/kvm_types.h      |   7 +
> > >  arch/riscv/include/asm/kvm_vcpu_timer.h |  44 ++
> > >  arch/riscv/include/uapi/asm/kvm.h       | 128 +++
> > >  arch/riscv/kernel/asm-offsets.c         | 156 ++++
> > >  arch/riscv/kvm/Kconfig                  |  36 +
> > >  arch/riscv/kvm/Makefile                 |  25 +
> > >  arch/riscv/kvm/main.c                   | 118 +++
> > >  arch/riscv/kvm/mmu.c                    | 802 +++++++++++++++++++
> > >  arch/riscv/kvm/tlb.S                    |  74 ++
> > >  arch/riscv/kvm/vcpu.c                   | 997 ++++++++++++++++++++++++
> > >  arch/riscv/kvm/vcpu_exit.c              | 701 +++++++++++++++++
> > >  arch/riscv/kvm/vcpu_sbi.c               | 185 +++++
> > >  arch/riscv/kvm/vcpu_switch.S            | 400 ++++++++++
> > >  arch/riscv/kvm/vcpu_timer.c             | 225 ++++++
> > >  arch/riscv/kvm/vm.c                     |  97 +++
> > >  arch/riscv/kvm/vmid.c                   | 120 +++
> > >  drivers/clocksource/timer-riscv.c       |   9 +
> > >  include/clocksource/timer-riscv.h       |  16 +
> > >  include/uapi/linux/kvm.h                |   8 +
> > >  25 files changed, 4699 insertions(+), 9 deletions(-)
> > >  create mode 100644 arch/riscv/include/asm/kvm_host.h
> > >  create mode 100644 arch/riscv/include/asm/kvm_types.h
> > >  create mode 100644 arch/riscv/include/asm/kvm_vcpu_timer.h
> > >  create mode 100644 arch/riscv/include/uapi/asm/kvm.h
> > >  create mode 100644 arch/riscv/kvm/Kconfig
> > >  create mode 100644 arch/riscv/kvm/Makefile
> > >  create mode 100644 arch/riscv/kvm/main.c
> > >  create mode 100644 arch/riscv/kvm/mmu.c
> > >  create mode 100644 arch/riscv/kvm/tlb.S
> > >  create mode 100644 arch/riscv/kvm/vcpu.c
> > >  create mode 100644 arch/riscv/kvm/vcpu_exit.c
> > >  create mode 100644 arch/riscv/kvm/vcpu_sbi.c
> > >  create mode 100644 arch/riscv/kvm/vcpu_switch.S
> > >  create mode 100644 arch/riscv/kvm/vcpu_timer.c
> > >  create mode 100644 arch/riscv/kvm/vm.c
> > >  create mode 100644 arch/riscv/kvm/vmid.c
> > >  create mode 100644 include/clocksource/timer-riscv.h
> > >
> > > --
> > > 2.25.1
> > >
> >
> >
> > --
> > Best Regards
> >  Guo Ren
> >
> > ML: https://lore.kernel.org/linux-csky/
> >
> > _______________________________________________
> > linux-riscv mailing list
> > linux-riscv at lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-riscv
>
>
>
> --
> Regards,
> Atish



-- 
Best Regards
 Guo Ren

ML: https://lore.kernel.org/linux-csky/