1 files changed, 30 insertions, 0 deletions

diff --git a/arch/x86/mm/pageattr_64.c b/arch/x86/mm/pageattr_64.c
index 4053832d4108..e1c860800ff1 100644
--- a/arch/x86/mm/pageattr_64.c
+++ b/arch/x86/mm/pageattr_64.c
@@ -260,3 +260,33 @@ void global_flush_tlb(void)
         on_each_cpu(flush_kernel_map, NULL, 1, 1);
 }
 EXPORT_SYMBOL(global_flush_tlb);
+
+#ifdef CONFIG_DEBUG_PAGEALLOC
+void kernel_map_pages(struct page *page, int numpages, int enable)
+{
+        if (PageHighMem(page))
+                return;
+        if (!enable) {
+                debug_check_no_locks_freed(page_address(page),
+                                           numpages * PAGE_SIZE);
+        }
+
+        /*
+         * If page allocator is not up yet then do not call c_p_a():
+         */
+        if (!debug_pagealloc_enabled)
+                return;
+
+        /*
+         * the return value is ignored - the calls cannot fail,
+         * large pages are disabled at boot time.
+         */
+        change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
+
+        /*
+         * we should perform an IPI and flush all tlbs,
+         * but that can deadlock->flush only current cpu.
+         */
+        __flush_tlb_all();
+}
+#endif