1 files changed, 15 insertions, 1 deletions

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index c483f4242079..d3a45d54547a 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -1040,11 +1040,25 @@ void __init mem_init(void)
                 (unsigned long)&_text, (unsigned long)&_etext,
                 ((unsigned long)&_etext - (unsigned long)&_text) >> 10);
 
+        /*
+         * Check boundaries twice: Some fundamental inconsistencies can
+         * be detected at build time already.
+         */
+#define __FIXADDR_TOP (-PAGE_SIZE)
+#ifdef CONFIG_HIGHMEM
+        BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP*PAGE_SIZE  > FIXADDR_START);
+        BUILD_BUG_ON(VMALLOC_END                        > PKMAP_BASE);
+#endif
+#define high_memory (-128UL << 20)
+        BUILD_BUG_ON(VMALLOC_START                      >= VMALLOC_END);
+#undef high_memory
+#undef __FIXADDR_TOP
+
 #ifdef CONFIG_HIGHMEM
         BUG_ON(PKMAP_BASE + LAST_PKMAP*PAGE_SIZE        > FIXADDR_START);
         BUG_ON(VMALLOC_END                              > PKMAP_BASE);
 #endif
-        BUG_ON(VMALLOC_START                            > VMALLOC_END);
+        BUG_ON(VMALLOC_START                            >= VMALLOC_END);
         BUG_ON((unsigned long)high_memory               > VMALLOC_START);
 
         if (boot_cpu_data.wp_works_ok < 0)