[PATCH] RISC-V: KVM: Allow Zbb extension for Guest/VM

From: Anup Patel
Date: Sat Apr 01 2023 - 07:28:23 EST


We extend the KVM ISA extension ONE_REG interface to allow KVM
user space to detect and enable Zbb extension for Guest/VM.

Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
---
arch/riscv/include/uapi/asm/kvm.h | 1 +
arch/riscv/kvm/vcpu.c | 2 ++
2 files changed, 3 insertions(+)

diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h
index d8ead5952ed9..47a7c3958229 100644
--- a/arch/riscv/include/uapi/asm/kvm.h
+++ b/arch/riscv/include/uapi/asm/kvm.h
@@ -106,6 +106,7 @@ enum KVM_RISCV_ISA_EXT_ID {
KVM_RISCV_ISA_EXT_SVINVAL,
KVM_RISCV_ISA_EXT_ZIHINTPAUSE,
KVM_RISCV_ISA_EXT_ZICBOM,
+ KVM_RISCV_ISA_EXT_ZBB,
KVM_RISCV_ISA_EXT_MAX,
};

diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
index 3112697cb12d..02b49cb94561 100644
--- a/arch/riscv/kvm/vcpu.c
+++ b/arch/riscv/kvm/vcpu.c
@@ -61,6 +61,7 @@ static const unsigned long kvm_isa_ext_arr[] = {
KVM_ISA_EXT_ARR(SSTC),
KVM_ISA_EXT_ARR(SVINVAL),
KVM_ISA_EXT_ARR(SVPBMT),
+ KVM_ISA_EXT_ARR(ZBB),
KVM_ISA_EXT_ARR(ZIHINTPAUSE),
KVM_ISA_EXT_ARR(ZICBOM),
};
@@ -99,6 +100,7 @@ static bool kvm_riscv_vcpu_isa_disable_allowed(unsigned long ext)
case KVM_RISCV_ISA_EXT_SSTC:
case KVM_RISCV_ISA_EXT_SVINVAL:
case KVM_RISCV_ISA_EXT_ZIHINTPAUSE:
+ case KVM_RISCV_ISA_EXT_ZBB:
return false;
default:
break;
--
2.34.1