Merge branch 'next' of git://git.kernel.org/pub/scm/virt/kvm/kvm

[firefly-linux-kernel-4.4.55.git] / arch / powerpc / kvm / book3s_64_mmu_hv.c

diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index 8e6401f2c16fd89421a29584410f47700d621470..80a57751758444a427797ecaff2a6f2e07a1ba03 100644 (file)
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
@@ -252,6 +252,8 @@ static long kvmppc_get_guest_page(struct kvm *kvm, unsigned long gfn,
                            !(memslot->userspace_addr & (s - 1))) {
                                start &= ~(s - 1);
                                pgsize = s;
+                               get_page(hpage);
+                               put_page(page);
                                page = hpage;
                        }
                }
@@ -275,11 +277,8 @@ static long kvmppc_get_guest_page(struct kvm *kvm, unsigned long gfn,
        err = 0;
 
  out:
-       if (got) {
-               if (PageHuge(page))
-                       page = compound_head(page);
+       if (got)
                put_page(page);
-       }
        return err;
 
  up_err:
@@ -673,8 +672,15 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
                SetPageDirty(page);
 
  out_put:
-       if (page)
-               put_page(page);
+       if (page) {
+               /*
+                * We drop pages[0] here, not page because page might
+                * have been set to the head page of a compound, but
+                * we have to drop the reference on the correct tail
+                * page to match the get inside gup()
+                */
+               put_page(pages[0]);
+       }
        return ret;
 
  out_unlock:
@@ -974,6 +980,7 @@ void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
                        pa = *physp;
                }
                page = pfn_to_page(pa >> PAGE_SHIFT);
+               get_page(page);
        } else {
                hva = gfn_to_hva_memslot(memslot, gfn);
                npages = get_user_pages_fast(hva, 1, 1, pages);
@@ -986,8 +993,6 @@ void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
                page = compound_head(page);
                psize <<= compound_order(page);
        }
-       if (!kvm->arch.using_mmu_notifiers)
-               get_page(page);
        offset = gpa & (psize - 1);
        if (nb_ret)
                *nb_ret = psize - offset;
@@ -998,7 +1003,6 @@ void kvmppc_unpin_guest_page(struct kvm *kvm, void *va)
 {
        struct page *page = virt_to_page(va);
 
-       page = compound_head(page);
        put_page(page);
 }