From ad03ff6b2870a5dd3f54b5eab7d52e498689f4b5 Mon Sep 17 00:00:00 2001 From: Anup Patel Date: Thu, 5 Jun 2025 11:44:46 +0530 Subject: RISC-V: KVM: Fix the size parameter check in SBI SFENCE calls [ Upstream commit 6aba0cb5bba6141158d5449f2cf53187b7f755f9 ] As-per the SBI specification, an SBI remote fence operation applies to the entire address space if either: 1) start_addr and size are both 0 2) size is equal to 2^XLEN-1 >From the above, only #1 is checked by SBI SFENCE calls so fix the size parameter check in SBI SFENCE calls to cover #2 as well. Fixes: 13acfec2dbcc ("RISC-V: KVM: Add remote HFENCE functions based on VCPU requests") Reviewed-by: Atish Patra Signed-off-by: Anup Patel Link: https://lore.kernel.org/r/20250605061458.196003-2-apatel@ventanamicro.com Signed-off-by: Anup Patel Signed-off-by: Sasha Levin --- arch/riscv/kvm/vcpu_sbi_replace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/riscv/kvm/vcpu_sbi_replace.c') diff --git a/arch/riscv/kvm/vcpu_sbi_replace.c b/arch/riscv/kvm/vcpu_sbi_replace.c index 5fbf3f94f1e8..9752d2ffff68 100644 --- a/arch/riscv/kvm/vcpu_sbi_replace.c +++ b/arch/riscv/kvm/vcpu_sbi_replace.c @@ -103,7 +103,7 @@ static int kvm_sbi_ext_rfence_handler(struct kvm_vcpu *vcpu, struct kvm_run *run kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_FENCE_I_SENT); break; case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA: - if (cp->a2 == 0 && cp->a3 == 0) + if ((cp->a2 == 0 && cp->a3 == 0) || cp->a3 == -1UL) kvm_riscv_hfence_vvma_all(vcpu->kvm, hbase, hmask); else kvm_riscv_hfence_vvma_gva(vcpu->kvm, hbase, hmask, @@ -111,7 +111,7 @@ static int kvm_sbi_ext_rfence_handler(struct kvm_vcpu *vcpu, struct kvm_run *run kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_HFENCE_VVMA_SENT); break; case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA_ASID: - if (cp->a2 == 0 && cp->a3 == 0) + if ((cp->a2 == 0 && cp->a3 == 0) || cp->a3 == -1UL) kvm_riscv_hfence_vvma_asid_all(vcpu->kvm, hbase, hmask, cp->a4); else -- cgit v1.2.3 From 76944f40a52a2c2631c038c49d94ea49ca3df9da Mon Sep 17 00:00:00 2001 From: Anup Patel Date: Thu, 5 Jun 2025 11:44:47 +0530 Subject: RISC-V: KVM: Don't treat SBI HFENCE calls as NOPs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 2e7be162996640bbe3b6da694cc064c511b8a5d9 ] 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 Signed-off-by: Sasha Levin --- arch/riscv/kvm/vcpu_sbi_replace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/riscv/kvm/vcpu_sbi_replace.c') diff --git a/arch/riscv/kvm/vcpu_sbi_replace.c b/arch/riscv/kvm/vcpu_sbi_replace.c index 9752d2ffff68..b17fad091bab 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; } -- cgit v1.2.3