diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index df4099dc1c682eb4af7c4af22badf4e4f3cd770c..65c7857a90ddfc6ff084c6817baba045ced0ad71 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -511,31 +511,30 @@ void *__kprobes text_poke(void *addr, const void *opcode, size_t len)
 	unsigned long flags;
 	char *vaddr;
 	int nr_pages = 2;
+	struct page *pages[2];
+	int i;
 
-	BUG_ON(len > sizeof(long));
-	BUG_ON((((long)addr + len - 1) & ~(sizeof(long) - 1))
-		- ((long)addr & ~(sizeof(long) - 1)));
-	if (kernel_text_address((unsigned long)addr)) {
-		struct page *pages[2] = { virt_to_page(addr),
-			virt_to_page(addr + PAGE_SIZE) };
-		if (!pages[1])
-			nr_pages = 1;
-		vaddr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
-		BUG_ON(!vaddr);
-		local_irq_save(flags);
-		memcpy(&vaddr[(unsigned long)addr & ~PAGE_MASK], opcode, len);
-		local_irq_restore(flags);
-		vunmap(vaddr);
+	if (!core_kernel_text((unsigned long)addr)) {
+		pages[0] = vmalloc_to_page(addr);
+		pages[1] = vmalloc_to_page(addr + PAGE_SIZE);
 	} else {
-		/*
-		 * modules are in vmalloc'ed memory, always writable.
-		 */
-		local_irq_save(flags);
-		memcpy(addr, opcode, len);
-		local_irq_restore(flags);
+		pages[0] = virt_to_page(addr);
+		WARN_ON(!PageReserved(pages[0]));
+		pages[1] = virt_to_page(addr + PAGE_SIZE);
 	}
+	BUG_ON(!pages[0]);
+	if (!pages[1])
+		nr_pages = 1;
+	vaddr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
+	BUG_ON(!vaddr);
+	local_irq_save(flags);
+	memcpy(&vaddr[(unsigned long)addr & ~PAGE_MASK], opcode, len);
+	local_irq_restore(flags);
+	vunmap(vaddr);
 	sync_core();
 	/* Could also do a CLFLUSH here to speed up CPU recovery; but
 	   that causes hangs on some VIA CPUs. */
+	for (i = 0; i < len; i++)
+		BUG_ON(((char *)addr)[i] != ((char *)opcode)[i]);
 	return addr;
 }
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 1ff7906a9a4dbc7afa6dfdd24f274e077cd26773..b798e7b92b1709819a5985f51d40782363da6c51 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -135,7 +135,7 @@ static __init void *spp_getpage(void)
 	return ptr;
 }
 
-static __init void
+static void
 set_pte_phys(unsigned long vaddr, unsigned long phys, pgprot_t prot)
 {
 	pgd_t *pgd;
@@ -173,7 +173,7 @@ set_pte_phys(unsigned long vaddr, unsigned long phys, pgprot_t prot)
 	new_pte = pfn_pte(phys >> PAGE_SHIFT, prot);
 
 	pte = pte_offset_kernel(pmd, vaddr);
-	if (!pte_none(*pte) &&
+	if (!pte_none(*pte) && pte_val(new_pte) &&
 	    pte_val(*pte) != (pte_val(new_pte) & __supported_pte_mask))
 		pte_ERROR(*pte);
 	set_pte(pte, new_pte);
@@ -214,8 +214,7 @@ void __init cleanup_highmap(void)
 }
 
 /* NOTE: this is meant to be run only at boot */
-void __init
-__set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
+void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
 {
 	unsigned long address = __fix_to_virt(idx);
 
diff --git a/include/asm-x86/fixmap.h b/include/asm-x86/fixmap.h
index 382eb271a89203cc2439fe8a1fb4b38250725648..5bd206973dca3cf184b859a1c2031ce6d3501ff3 100644
--- a/include/asm-x86/fixmap.h
+++ b/include/asm-x86/fixmap.h
@@ -1,5 +1,13 @@
+#ifndef _ASM_FIXMAP_H
+#define _ASM_FIXMAP_H
+
 #ifdef CONFIG_X86_32
 # include "fixmap_32.h"
 #else
 # include "fixmap_64.h"
 #endif
+
+#define clear_fixmap(idx)			\
+	__set_fixmap(idx, 0, __pgprot(0))
+
+#endif
diff --git a/include/asm-x86/fixmap_32.h b/include/asm-x86/fixmap_32.h
index eb1665125c443fac0cb1a474b2d7ae4d4c76f4de..4b96148e90c15587f715969f2ff4c6fd5a07d4d8 100644
--- a/include/asm-x86/fixmap_32.h
+++ b/include/asm-x86/fixmap_32.h
@@ -10,8 +10,8 @@
  * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
  */
 
-#ifndef _ASM_FIXMAP_H
-#define _ASM_FIXMAP_H
+#ifndef _ASM_FIXMAP_32_H
+#define _ASM_FIXMAP_32_H
 
 
 /* used by vmalloc.c, vsyscall.lds.S.
@@ -121,9 +121,6 @@ extern void reserve_top_address(unsigned long reserve);
 #define set_fixmap_nocache(idx, phys)			\
 	__set_fixmap(idx, phys, PAGE_KERNEL_NOCACHE)
 
-#define clear_fixmap(idx)			\
-	__set_fixmap(idx, 0, __pgprot(0))
-
 #define FIXADDR_TOP	((unsigned long)__FIXADDR_TOP)
 
 #define __FIXADDR_SIZE	(__end_of_permanent_fixed_addresses << PAGE_SHIFT)
diff --git a/include/asm-x86/fixmap_64.h b/include/asm-x86/fixmap_64.h
index f3d76858c0e6f4b5c380736a1db9b79afcc4242f..355d26a75a821a87aa298ee52f79617015dc7a8e 100644
--- a/include/asm-x86/fixmap_64.h
+++ b/include/asm-x86/fixmap_64.h
@@ -8,8 +8,8 @@
  * Copyright (C) 1998 Ingo Molnar
  */
 
-#ifndef _ASM_FIXMAP_H
-#define _ASM_FIXMAP_H
+#ifndef _ASM_FIXMAP_64_H
+#define _ASM_FIXMAP_64_H
 
 #include <linux/kernel.h>
 #include <asm/apicdef.h>