From: Anup Patel Date: Thu, 5 Jun 2025 06:14:47 +0000 (+0530) Subject: RISC-V: KVM: Don't treat SBI HFENCE calls as NOPs X-Git-Tag: v6.16-rc3~7^2~3^2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=2e7be162996640bbe3b6da694cc064c511b8a5d9;p=thirdparty%2Flinux.git RISC-V: KVM: Don't treat SBI HFENCE calls as NOPs The SBI specification clearly states that SBI HFENCE calls should return SBI_ERR_NOT_SUPPORTED when one of the target hart doesn’t support hypervisor extension (aka nested virtualization in-case of KVM RISC-V). Fixes: c7fa3c48de86 ("RISC-V: KVM: Treat SBI HFENCE calls as NOPs") Reviewed-by: Atish Patra Signed-off-by: Anup Patel Link: https://lore.kernel.org/r/20250605061458.196003-3-apatel@ventanamicro.com Signed-off-by: Anup Patel --- diff --git a/arch/riscv/kvm/vcpu_sbi_replace.c b/arch/riscv/kvm/vcpu_sbi_replace.c index 9752d2ffff683..b17fad091babd 100644 --- a/arch/riscv/kvm/vcpu_sbi_replace.c +++ b/arch/riscv/kvm/vcpu_sbi_replace.c @@ -127,9 +127,9 @@ static int kvm_sbi_ext_rfence_handler(struct kvm_vcpu *vcpu, struct kvm_run *run case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA_ASID: /* * Until nested virtualization is implemented, the - * SBI HFENCE calls should be treated as NOPs + * SBI HFENCE calls should return not supported + * hence fallthrough. */ - break; default: retdata->err_val = SBI_ERR_NOT_SUPPORTED; }