5 files changed, 46 insertions, 29 deletions

diff --git a/arch/x86/mm/ident_map.c b/arch/x86/mm/ident_map.c
index ec21796..4473cb4 100644
--- a/arch/x86/mm/ident_map.c
+++ b/arch/x86/mm/ident_map.c
@@ -3,15 +3,17 @@
  * included by both the compressed kernel and the regular kernel.
  */
 
-static void ident_pmd_init(unsigned long pmd_flag, pmd_t *pmd_page,
+static void ident_pmd_init(struct x86_mapping_info *info, pmd_t *pmd_page,
 			   unsigned long addr, unsigned long end)
 {
 	addr &= PMD_MASK;
 	for (; addr < end; addr += PMD_SIZE) {
 		pmd_t *pmd = pmd_page + pmd_index(addr);
 
-		if (!pmd_present(*pmd))
-			set_pmd(pmd, __pmd(addr | pmd_flag));
+		if (pmd_present(*pmd))
+			continue;
+
+		set_pmd(pmd, __pmd((addr - info->offset) | info->pmd_flag));
 	}
 }
 
@@ -30,13 +32,13 @@ static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
 
 		if (pud_present(*pud)) {
 			pmd = pmd_offset(pud, 0);
-			ident_pmd_init(info->pmd_flag, pmd, addr, next);
+			ident_pmd_init(info, pmd, addr, next);
 			continue;
 		}
 		pmd = (pmd_t *)info->alloc_pgt_page(info->context);
 		if (!pmd)
 			return -ENOMEM;
-		ident_pmd_init(info->pmd_flag, pmd, addr, next);
+		ident_pmd_init(info, pmd, addr, next);
 		set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
 	}
 
@@ -44,14 +46,15 @@ static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
 }
 
 int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
-			      unsigned long addr, unsigned long end)
+			      unsigned long pstart, unsigned long pend)
 {
+	unsigned long addr = pstart + info->offset;
+	unsigned long end = pend + info->offset;
 	unsigned long next;
 	int result;
-	int off = info->kernel_mapping ? pgd_index(__PAGE_OFFSET) : 0;
 
 	for (; addr < end; addr = next) {
-		pgd_t *pgd = pgd_page + pgd_index(addr) + off;
+		pgd_t *pgd = pgd_page + pgd_index(addr);
 		pud_t *pud;
 
 		next = (addr & PGDIR_MASK) + PGDIR_SIZE;
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 6209289..d28a2d7 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -122,8 +122,18 @@ __ref void *alloc_low_pages(unsigned int num)
 	return __va(pfn << PAGE_SHIFT);
 }
 
-/* need 3 4k for initial PMD_SIZE,  3 4k for 0-ISA_END_ADDRESS */
-#define INIT_PGT_BUF_SIZE	(6 * PAGE_SIZE)
+/*
+ * By default need 3 4k for initial PMD_SIZE,  3 4k for 0-ISA_END_ADDRESS.
+ * With KASLR memory randomization, depending on the machine e820 memory
+ * and the PUD alignment. We may need twice more pages when KASLR memory
+ * randomization is enabled.
+ */
+#ifndef CONFIG_RANDOMIZE_MEMORY
+#define INIT_PGD_PAGE_COUNT      6
+#else
+#define INIT_PGD_PAGE_COUNT      12
+#endif
+#define INIT_PGT_BUF_SIZE	(INIT_PGD_PAGE_COUNT * PAGE_SIZE)
 RESERVE_BRK(early_pgt_alloc, INIT_PGT_BUF_SIZE);
 void  __init early_alloc_pgt_buf(void)
 {
diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
index 26dccd6..bda8d5e 100644
--- a/arch/x86/mm/kaslr.c
+++ b/arch/x86/mm/kaslr.c
@@ -77,7 +77,7 @@ static inline unsigned long get_padding(struct kaslr_memory_region *region)
  */
 static inline bool kaslr_memory_enabled(void)
 {
-	return kaslr_enabled() && !config_enabled(CONFIG_KASAN);
+	return kaslr_enabled() && !IS_ENABLED(CONFIG_KASAN);
 }
 
 /* Initialize base and padding for each memory region randomized with KASLR */
@@ -97,7 +97,7 @@ void __init kernel_randomize_memory(void)
 	 * add padding if needed (especially for memory hotplug support).
 	 */
 	BUG_ON(kaslr_regions[0].base != &page_offset_base);
-	memory_tb = ((max_pfn << PAGE_SHIFT) >> TB_SHIFT) +
+	memory_tb = DIV_ROUND_UP(max_pfn << PAGE_SHIFT, 1UL << TB_SHIFT) +
 		CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING;
 
 	/* Adapt phyiscal memory region size based on available memory */
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 849dc09..e3353c9 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -917,11 +917,11 @@ static void populate_pte(struct cpa_data *cpa,
 	}
 }
 
-static int populate_pmd(struct cpa_data *cpa,
-			unsigned long start, unsigned long end,
-			unsigned num_pages, pud_t *pud, pgprot_t pgprot)
+static long populate_pmd(struct cpa_data *cpa,
+			 unsigned long start, unsigned long end,
+			 unsigned num_pages, pud_t *pud, pgprot_t pgprot)
 {
-	unsigned int cur_pages = 0;
+	long cur_pages = 0;
 	pmd_t *pmd;
 	pgprot_t pmd_pgprot;
 
@@ -991,12 +991,12 @@ static int populate_pmd(struct cpa_data *cpa,
 	return num_pages;
 }
 
-static int populate_pud(struct cpa_data *cpa, unsigned long start, pgd_t *pgd,
-			pgprot_t pgprot)
+static long populate_pud(struct cpa_data *cpa, unsigned long start, pgd_t *pgd,
+			 pgprot_t pgprot)
 {
 	pud_t *pud;
 	unsigned long end;
-	int cur_pages = 0;
+	long cur_pages = 0;
 	pgprot_t pud_pgprot;
 
 	end = start + (cpa->numpages << PAGE_SHIFT);
@@ -1052,7 +1052,7 @@ static int populate_pud(struct cpa_data *cpa, unsigned long start, pgd_t *pgd,
 
 	/* Map trailing leftover */
 	if (start < end) {
-		int tmp;
+		long tmp;
 
 		pud = pud_offset(pgd, start);
 		if (pud_none(*pud))
@@ -1078,7 +1078,7 @@ static int populate_pgd(struct cpa_data *cpa, unsigned long addr)
 	pgprot_t pgprot = __pgprot(_KERNPG_TABLE);
 	pud_t *pud = NULL;	/* shut up gcc */
 	pgd_t *pgd_entry;
-	int ret;
+	long ret;
 
 	pgd_entry = cpa->pgd + pgd_index(addr);
 
@@ -1327,7 +1327,8 @@ static int cpa_process_alias(struct cpa_data *cpa)
 
 static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias)
 {
-	int ret, numpages = cpa->numpages;
+	unsigned long numpages = cpa->numpages;
+	int ret;
 
 	while (numpages) {
 		/*
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index ecb1b69..170cc4f 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -927,9 +927,10 @@ int track_pfn_copy(struct vm_area_struct *vma)
 }
 
 /*
- * prot is passed in as a parameter for the new mapping. If the vma has a
- * linear pfn mapping for the entire range reserve the entire vma range with
- * single reserve_pfn_range call.
+ * prot is passed in as a parameter for the new mapping. If the vma has
+ * a linear pfn mapping for the entire range, or no vma is provided,
+ * reserve the entire pfn + size range with single reserve_pfn_range
+ * call.
  */
 int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
 		    unsigned long pfn, unsigned long addr, unsigned long size)
@@ -938,11 +939,12 @@ int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
 	enum page_cache_mode pcm;
 
 	/* reserve the whole chunk starting from paddr */
-	if (addr == vma->vm_start && size == (vma->vm_end - vma->vm_start)) {
+	if (!vma || (addr == vma->vm_start
+				&& size == (vma->vm_end - vma->vm_start))) {
 		int ret;
 
 		ret = reserve_pfn_range(paddr, size, prot, 0);
-		if (!ret)
+		if (ret == 0 && vma)
 			vma->vm_flags |= VM_PAT;
 		return ret;
 	}
@@ -997,7 +999,7 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
 	resource_size_t paddr;
 	unsigned long prot;
 
-	if (!(vma->vm_flags & VM_PAT))
+	if (vma && !(vma->vm_flags & VM_PAT))
 		return;
 
 	/* free the chunk starting from pfn or the whole chunk */
@@ -1011,7 +1013,8 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
 		size = vma->vm_end - vma->vm_start;
 	}
 	free_pfn_range(paddr, size);
-	vma->vm_flags &= ~VM_PAT;
+	if (vma)
+		vma->vm_flags &= ~VM_PAT;
 }
 
 /*