>This patch makes the emulation_type always set irrelevant to the return
>code. kvm_mmu_page_fault() is the only caller of kvm_mmu_do_page_fault(),
>and references the value only when PF_RET_EMULATE is returned. Therefore,
>this adjustment doesn't affect functionality.
This is benign. But what's the benefit of doing this?
>+static inline int __kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
>+ u64 err, bool prefetch, int *emulation_type)
> {
> struct kvm_page_fault fault = {
> .addr = cr2_or_gpa,
>@@ -318,14 +318,6 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
> fault.slot = kvm_vcpu_gfn_to_memslot(vcpu, fault.gfn);
> }
>
>- /*
>- * Async #PF "faults", a.k.a. prefetch faults, are not faults from the
>- * guest perspective and have already been counted at the time of the
>- * original fault.
>- */
>- if (!prefetch)
>- vcpu->stat.pf_taken++;
>-
> if (IS_ENABLED(CONFIG_MITIGATION_RETPOLINE) && fault.is_tdp)
> r = kvm_tdp_page_fault(vcpu, &fault);
> else
>@@ -333,12 +325,30 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
>
> if (r == RET_PF_EMULATE && fault.is_private) {
> kvm_mmu_prepare_memory_fault_exit(vcpu, &fault);
>- return -EFAULT;
>+ r = -EFAULT;
> }
>
> if (fault.write_fault_to_shadow_pgtable && emulation_type)
> *emulation_type |= EMULTYPE_WRITE_PF_TO_SP;
>
>+ return r;
>+}
>+
>+static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
>+ u64 err, bool prefetch, int *emulation_type)
>+{
>+ int r;
>+
>+ /*
>+ * Async #PF "faults", a.k.a. prefetch faults, are not faults from the
>+ * guest perspective and have already been counted at the time of the
>+ * original fault.
>+ */
>+ if (!prefetch)
>+ vcpu->stat.pf_taken++;
>+
>+ r = __kvm_mmu_do_page_fault(vcpu, cr2_or_gpa, err, prefetch, emulation_type);
bail out if r < 0?
>+
> /*
> * Similar to above, prefetch faults aren't truly spurious, and the
> * async #PF path doesn't do emulation. Do count faults that are fixed
>--
>2.43.2
>
>
