diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c index 78211aed36fa6a3dcb2785e68442272131ded9c5..46d6929958306002accd5ad5586989915c4dbe0a 100644 --- a/arch/riscv/kvm/mmu.c +++ b/arch/riscv/kvm/mmu.c @@ -628,6 +628,13 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, !(memslot->flags & KVM_MEM_READONLY)) ? true : false; unsigned long vma_pagesize, mmu_seq; + /* We need minimum second+third level pages */ + ret = kvm_mmu_topup_memory_cache(pcache, gstage_pgd_levels); + if (ret) { + kvm_err("Failed to topup G-stage cache\n"); + return ret; + } + mmap_read_lock(current->mm); vma = vma_lookup(current->mm, hva); @@ -648,6 +655,15 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, if (vma_pagesize == PMD_SIZE || vma_pagesize == PUD_SIZE) gfn = (gpa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT; + /* + * Read mmu_invalidate_seq so that KVM can detect if the results of + * vma_lookup() or gfn_to_pfn_prot() become stale priort to acquiring + * kvm->mmu_lock. + * + * Rely on mmap_read_unlock() for an implicit smp_rmb(), which pairs + * with the smp_wmb() in kvm_mmu_invalidate_end(). + */ + mmu_seq = kvm->mmu_invalidate_seq; mmap_read_unlock(current->mm); if (vma_pagesize != PUD_SIZE && @@ -657,15 +673,6 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, return -EFAULT; } - /* We need minimum second+third level pages */ - ret = kvm_mmu_topup_memory_cache(pcache, gstage_pgd_levels); - if (ret) { - kvm_err("Failed to topup G-stage cache\n"); - return ret; - } - - mmu_seq = kvm->mmu_invalidate_seq; - hfn = gfn_to_pfn_prot(kvm, gfn, is_write, &writable); if (hfn == KVM_PFN_ERR_HWPOISON) { send_sig_mceerr(BUS_MCEERR_AR, (void __user *)hva,