[PATCH 3/4] KVM: arm/arm64: Remove unnecessary CMOs when creating HYP page tables

[Marc Zyngier]

There is no need to perform cache maintenance operations when
creating the HYP page tables if we have the multiprocessing
extensions. ARMv7 mandates them with the virtualization support,
and ARMv8 just mandates them unconditionally.

Let's remove these operations.

Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
 virt/kvm/arm/mmu.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index ba66bf7ae299..acbfea09578c 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -578,7 +578,6 @@ static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
 		pte = pte_offset_kernel(pmd, addr);
 		kvm_set_pte(pte, pfn_pte(pfn, prot));
 		get_page(virt_to_page(pte));
-		kvm_flush_dcache_to_poc(pte, sizeof(*pte));
 		pfn++;
 	} while (addr += PAGE_SIZE, addr != end);
 }
@@ -605,7 +604,6 @@ static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
 			}
 			pmd_populate_kernel(NULL, pmd, pte);
 			get_page(virt_to_page(pmd));
-			kvm_flush_dcache_to_poc(pmd, sizeof(*pmd));
 		}
 
 		next = pmd_addr_end(addr, end);
@@ -638,7 +636,6 @@ static int create_hyp_pud_mappings(pgd_t *pgd, unsigned long start,
 			}
 			pud_populate(NULL, pud, pmd);
 			get_page(virt_to_page(pud));
-			kvm_flush_dcache_to_poc(pud, sizeof(*pud));
 		}
 
 		next = pud_addr_end(addr, end);
@@ -675,7 +672,6 @@ static int __create_hyp_mappings(pgd_t *pgdp, unsigned long ptrs_per_pgd,
 			}
 			pgd_populate(NULL, pgd, pud);
 			get_page(virt_to_page(pgd));
-			kvm_flush_dcache_to_poc(pgd, sizeof(*pgd));
 		}
 
 		next = pgd_addr_end(addr, end);
@@ -685,6 +681,7 @@ static int __create_hyp_mappings(pgd_t *pgdp, unsigned long ptrs_per_pgd,
 		pfn += (next - addr) >> PAGE_SHIFT;
 	} while (addr = next, addr != end);
 out:
+	dsb(ishst);
 	mutex_unlock(&kvm_hyp_pgd_mutex);
 	return err;
 }
-- 
2.14.2