4 files changed, 51 insertions, 7 deletions

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index f4cee9028cf0..1739358b444d 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -801,8 +801,10 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address,
 	up_read(&mm->mmap_sem);
 
 	/* Kernel mode? Handle exceptions or die: */
-	if (!(error_code & PF_USER))
+	if (!(error_code & PF_USER)) {
 		no_context(regs, error_code, address);
+		return;
+	}
 
 	/* User-space => ok to do another page fault: */
 	if (is_prefetch(regs, error_code, address))
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 5a4398a6006b..7d095ad54535 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -49,6 +49,7 @@
 #include <asm/numa.h>
 #include <asm/cacheflush.h>
 #include <asm/init.h>
+#include <linux/bootmem.h>
 
 static unsigned long dma_reserve __initdata;
 
@@ -615,6 +616,21 @@ void __init paging_init(void)
  */
 #ifdef CONFIG_MEMORY_HOTPLUG
 /*
+ * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
+ * updating.
+ */
+static void  update_end_of_memory_vars(u64 start, u64 size)
+{
+	unsigned long end_pfn = PFN_UP(start + size);
+
+	if (end_pfn > max_pfn) {
+		max_pfn = end_pfn;
+		max_low_pfn = end_pfn;
+		high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
+	}
+}
+
+/*
  * Memory is added always to NORMAL zone. This means you will never get
  * additional DMA/DMA32 memory.
  */
@@ -633,6 +649,9 @@ int arch_add_memory(int nid, u64 start, u64 size)
 	ret = __add_pages(nid, zone, start_pfn, nr_pages);
 	WARN_ON_ONCE(ret);
 
+	/* update max_pfn, max_low_pfn and high_memory */
+	update_end_of_memory_vars(start, size);
+
 	return ret;
 }
 EXPORT_SYMBOL_GPL(arch_add_memory);
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index ed34f5e35999..c9ba9deafe83 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -6,6 +6,14 @@
 
 #define PGALLOC_GFP GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO
 
+#ifdef CONFIG_HIGHPTE
+#define PGALLOC_USER_GFP __GFP_HIGHMEM
+#else
+#define PGALLOC_USER_GFP 0
+#endif
+
+gfp_t __userpte_alloc_gfp = PGALLOC_GFP | PGALLOC_USER_GFP;
+
 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
 	return (pte_t *)__get_free_page(PGALLOC_GFP);
@@ -15,16 +23,29 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
 {
 	struct page *pte;
 
-#ifdef CONFIG_HIGHPTE
-	pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0);
-#else
-	pte = alloc_pages(PGALLOC_GFP, 0);
-#endif
+	pte = alloc_pages(__userpte_alloc_gfp, 0);
 	if (pte)
 		pgtable_page_ctor(pte);
 	return pte;
 }
 
+static int __init setup_userpte(char *arg)
+{
+	if (!arg)
+		return -EINVAL;
+
+	/*
+	 * "userpte=nohigh" disables allocation of user pagetables in
+	 * high memory.
+	 */
+	if (strcmp(arg, "nohigh") == 0)
+		__userpte_alloc_gfp &= ~__GFP_HIGHMEM;
+	else
+		return -EINVAL;
+	return 0;
+}
+early_param("userpte", setup_userpte);
+
 void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte)
 {
 	pgtable_page_dtor(pte);
diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c
index dbb5381f7b3b..3871c600c4f3 100644
--- a/arch/x86/mm/srat_64.c
+++ b/arch/x86/mm/srat_64.c
@@ -229,9 +229,11 @@ update_nodes_add(int node, unsigned long start, unsigned long end)
 			printk(KERN_ERR "SRAT: Hotplug zone not continuous. Partly ignored\n");
 	}
 
-	if (changed)
+	if (changed) {
+		node_set(node, cpu_nodes_parsed);
 		printk(KERN_INFO "SRAT: hot plug zone found %Lx - %Lx\n",
 				 nd->start, nd->end);
+	}
 }
 
 /* Callback for parsing of the Proximity Domain <-> Memory Area mappings */