Re: [PATCH v12 58/84] KVM: RISC-V: Use kvm_faultin_pfn() when mapping pfns into the guest

Andrew Jones
2024-07-31T08:11:52Z

On Fri, Jul 26, 2024 at 04:52:07PM GMT, Sean Christopherson wrote:
> Convert RISC-V to __kvm_faultin_pfn()+kvm_release_faultin_page(), which
> are new APIs to consolidate arch code and provide consistent behavior
> across all KVM architectures.
>
> Signed-off-by: Sean Christopherson <seanjc@google.com>
> ---
> arch/riscv/kvm/mmu.c | 11 ++++-------
> 1 file changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
> index 806f68e70642..f73d6a79a78c 100644
> --- a/arch/riscv/kvm/mmu.c
> +++ b/arch/riscv/kvm/mmu.c
> @@ -601,6 +601,7 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
> bool logging = (memslot->dirty_bitmap &&
> !(memslot->flags & KVM_MEM_READONLY)) ? true : false;
> unsigned long vma_pagesize, mmu_seq;
> + struct page *page;
>
> /* We need minimum second+third level pages */
> ret = kvm_mmu_topup_memory_cache(pcache, gstage_pgd_levels);
> @@ -631,7 +632,7 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
>
> /*
> * 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
> + * vma_lookup() or __kvm_faultin_pfn() become stale priort to acquiring
^ while here
could fix this typo

> * kvm->mmu_lock.
> *
> * Rely on mmap_read_unlock() for an implicit smp_rmb(), which pairs
> @@ -647,7 +648,7 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
> return -EFAULT;
> }
>
> - hfn = gfn_to_pfn_prot(kvm, gfn, is_write, &writable);
> + hfn = kvm_faultin_pfn(vcpu, gfn, is_write, &writable, &page);
> if (hfn == KVM_PFN_ERR_HWPOISON) {
> send_sig_mceerr(BUS_MCEERR_AR, (void __user *)hva,
> vma_pageshift, current);
> @@ -681,11 +682,7 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
> kvm_err("Failed to map in G-stage\n");
>
> out_unlock:
> - if ((!ret || ret == -EEXIST) && writable)
> - kvm_set_pfn_dirty(hfn);
> - else
> - kvm_release_pfn_clean(hfn);
> -
> + kvm_release_faultin_page(kvm, page, ret && ret != -EEXIST, writable);
> spin_unlock(&kvm->mmu_lock);
> return ret;
> }
> --
> 2.46.0.rc1.232.g9752f9e123-goog
>
>

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>