Re: [PATCH v8 13/14] RISC-V: KVM: add support for FWFT SBI extension

2025-05-23T12:19:30+02:00, Clément Léger cleger@rivosinc.com:

+++ b/arch/riscv/kvm/vcpu_sbi_fwft.c +static const enum sbi_fwft_feature_t kvm_fwft_defined_features[] = {

• SBI_FWFT_MISALIGNED_EXC_DELEG,
• SBI_FWFT_LANDING_PAD,
• SBI_FWFT_SHADOW_STACK,
• SBI_FWFT_DOUBLE_TRAP,
• SBI_FWFT_PTE_AD_HW_UPDATING,
• SBI_FWFT_POINTER_MASKING_PMLEN,

+};

How will userspace control which subset of these features is allowed in the guest?

(We can reuse the KVM SBI extension interface if we don't want to add a FWFT specific ONE_REG.)

Thanks.