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Subject[PATCH RFC 0/3] Implement guest time scaling in RISC-V KVM
Date
This series implements guest time scaling based on RDTIME instruction
emulation so that we can allow migrating Guest/VM across Hosts with
different time frequency.

Why not through para-virt. From arm's experience[1], para-virt implementation
doesn't really solve the problem for the following two main reasons:
- RDTIME not only be used in linux, but also in firmware and userspace.
- It is difficult to be compatible with nested virtualization.

[1] https://lore.kernel.org/patchwork/cover/1288153/

Yifei Jiang (3):
RISC-V: KVM: Change the method of calculating cycles to nanoseconds
RISC-V: KVM: Support dynamic time frequency from userspace
RISC-V: KVM: Implement guest time scaling

arch/riscv/include/asm/csr.h | 3 ++
arch/riscv/include/asm/kvm_vcpu_timer.h | 13 +++++--
arch/riscv/kvm/vcpu_exit.c | 35 +++++++++++++++++
arch/riscv/kvm/vcpu_timer.c | 51 ++++++++++++++++++++++---
4 files changed, 93 insertions(+), 9 deletions(-)

--
2.19.1

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