1 files changed, 52 insertions, 9 deletions

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index dbae185511cd..3b246ae40c8f 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -209,7 +209,7 @@ static void sync_global_pgds_l4(unsigned long start, unsigned long end)
  * When memory was added make sure all the processes MM have
  * suitable PGD entries in the local PGD level page.
  */
-void sync_global_pgds(unsigned long start, unsigned long end)
+static void sync_global_pgds(unsigned long start, unsigned long end)
 {
 	if (pgtable_l5_enabled())
 		sync_global_pgds_l5(start, end);
@@ -817,7 +817,6 @@ void __init initmem_init(void)
 
 void __init paging_init(void)
 {
-	sparse_memory_present_with_active_regions(MAX_NUMNODES);
 	sparse_init();
 
 	/*
@@ -1238,6 +1237,51 @@ static void __init register_page_bootmem_info(void)
 #endif
 }
 
+/*
+ * Pre-allocates page-table pages for the vmalloc area in the kernel page-table.
+ * Only the level which needs to be synchronized between all page-tables is
+ * allocated because the synchronization can be expensive.
+ */
+static void __init preallocate_vmalloc_pages(void)
+{
+	unsigned long addr;
+	const char *lvl;
+
+	for (addr = VMALLOC_START; addr <= VMALLOC_END; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
+		pgd_t *pgd = pgd_offset_k(addr);
+		p4d_t *p4d;
+		pud_t *pud;
+
+		lvl = "p4d";
+		p4d = p4d_alloc(&init_mm, pgd, addr);
+		if (!p4d)
+			goto failed;
+
+		/*
+		 * With 5-level paging the P4D level is not folded. So the PGDs
+		 * are now populated and there is no need to walk down to the
+		 * PUD level.
+		 */
+		if (pgtable_l5_enabled())
+			continue;
+
+		lvl = "pud";
+		pud = pud_alloc(&init_mm, p4d, addr);
+		if (!pud)
+			goto failed;
+	}
+
+	return;
+
+failed:
+
+	/*
+	 * The pages have to be there now or they will be missing in
+	 * process page-tables later.
+	 */
+	panic("Failed to pre-allocate %s pages for vmalloc area\n", lvl);
+}
+
 void __init mem_init(void)
 {
 	pci_iommu_alloc();
@@ -1261,6 +1305,8 @@ void __init mem_init(void)
 	if (get_gate_vma(&init_mm))
 		kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER);
 
+	preallocate_vmalloc_pages();
+
 	mem_init_print_info(NULL);
 }
 
@@ -1463,10 +1509,7 @@ static int __meminit vmemmap_populate_hugepages(unsigned long start,
 		if (pmd_none(*pmd)) {
 			void *p;
 
-			if (altmap)
-				p = altmap_alloc_block_buf(PMD_SIZE, altmap);
-			else
-				p = vmemmap_alloc_block_buf(PMD_SIZE, node);
+			p = vmemmap_alloc_block_buf(PMD_SIZE, node, altmap);
 			if (p) {
 				pte_t entry;
 
@@ -1493,7 +1536,7 @@ static int __meminit vmemmap_populate_hugepages(unsigned long start,
 			vmemmap_verify((pte_t *)pmd, node, addr, next);
 			continue;
 		}
-		if (vmemmap_populate_basepages(addr, next, node))
+		if (vmemmap_populate_basepages(addr, next, node, NULL))
 			return -ENOMEM;
 	}
 	return 0;
@@ -1505,7 +1548,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 	int err;
 
 	if (end - start < PAGES_PER_SECTION * sizeof(struct page))
-		err = vmemmap_populate_basepages(start, end, node);
+		err = vmemmap_populate_basepages(start, end, node, NULL);
 	else if (boot_cpu_has(X86_FEATURE_PSE))
 		err = vmemmap_populate_hugepages(start, end, node, altmap);
 	else if (altmap) {
@@ -1513,7 +1556,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 				__func__);
 		err = -ENOMEM;
 	} else
-		err = vmemmap_populate_basepages(start, end, node);
+		err = vmemmap_populate_basepages(start, end, node, NULL);
 	if (!err)
 		sync_global_pgds(start, end - 1);
 	return err;