Merge branch 'linus' into tracing/hw-breakpoints

Conflicts:
	arch/x86/Kconfig
	arch/x86/kernel/traps.c
	arch/x86/power/cpu.c
	arch/x86/power/cpu_32.c
	kernel/Makefile

Semantic conflict:
	arch/x86/kernel/hw_breakpoint.c

Merge reason: Resolve the conflicts, move from put_cpu_no_sched() to
              put_cpu() in arch/x86/kernel/hw_breakpoint.c.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

26 files changed, 1466 insertions, 316 deletions

diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile
index fdd30d08ab52..eefdeee8a871 100644
--- a/arch/x86/mm/Makefile
+++ b/arch/x86/mm/Makefile
@@ -10,6 +10,8 @@ obj-$(CONFIG_X86_PTDUMP)	+= dump_pagetables.o
 
 obj-$(CONFIG_HIGHMEM)		+= highmem_32.o
 
+obj-$(CONFIG_KMEMCHECK)		+= kmemcheck/
+
 obj-$(CONFIG_MMIOTRACE)		+= mmiotrace.o
 mmiotrace-y			:= kmmio.o pf_in.o mmio-mod.o
 obj-$(CONFIG_MMIOTRACE_TEST)	+= testmmiotrace.o
diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
index e7277cbcfb40..a725b7f760ae 100644
--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c
@@ -161,13 +161,14 @@ static void note_page(struct seq_file *m, struct pg_state *st,
 		   st->current_address >= st->marker[1].start_address) {
 		const char *unit = units;
 		unsigned long delta;
+		int width = sizeof(unsigned long) * 2;
 
 		/*
 		 * Now print the actual finished series
 		 */
-		seq_printf(m, "0x%p-0x%p   ",
-			   (void *)st->start_address,
-			   (void *)st->current_address);
+		seq_printf(m, "0x%0*lx-0x%0*lx   ",
+			   width, st->start_address,
+			   width, st->current_address);
 
 		delta = (st->current_address - st->start_address) >> 10;
 		while (!(delta & 1023) && unit[1]) {
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index a03b7279efa0..baa0e86adfbc 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -3,40 +3,18 @@
  *  Copyright (C) 2001, 2002 Andi Kleen, SuSE Labs.
  *  Copyright (C) 2008-2009, Red Hat Inc., Ingo Molnar
  */
-#include <linux/interrupt.h>
-#include <linux/mmiotrace.h>
-#include <linux/bootmem.h>
-#include <linux/compiler.h>
-#include <linux/highmem.h>
-#include <linux/kprobes.h>
-#include <linux/uaccess.h>
-#include <linux/vmalloc.h>
-#include <linux/vt_kern.h>
-#include <linux/signal.h>
-#include <linux/kernel.h>
-#include <linux/ptrace.h>
-#include <linux/string.h>
-#include <linux/module.h>
-#include <linux/kdebug.h>
-#include <linux/errno.h>
-#include <linux/magic.h>
-#include <linux/sched.h>
-#include <linux/types.h>
-#include <linux/init.h>
-#include <linux/mman.h>
-#include <linux/tty.h>
-#include <linux/smp.h>
-#include <linux/mm.h>
-
-#include <asm-generic/sections.h>
-
-#include <asm/tlbflush.h>
-#include <asm/pgalloc.h>
-#include <asm/segment.h>
-#include <asm/system.h>
-#include <asm/proto.h>
-#include <asm/traps.h>
-#include <asm/desc.h>
+#include <linux/magic.h>		/* STACK_END_MAGIC		*/
+#include <linux/sched.h>		/* test_thread_flag(), ...	*/
+#include <linux/kdebug.h>		/* oops_begin/end, ...		*/
+#include <linux/module.h>		/* search_exception_table	*/
+#include <linux/bootmem.h>		/* max_low_pfn			*/
+#include <linux/kprobes.h>		/* __kprobes, ...		*/
+#include <linux/mmiotrace.h>		/* kmmio_handler, ...		*/
+#include <linux/perf_counter.h>		/* perf_swcounter_event		*/
+
+#include <asm/traps.h>			/* dotraplinkage, ...		*/
+#include <asm/pgalloc.h>		/* pgd_*(), ...			*/
+#include <asm/kmemcheck.h>		/* kmemcheck_*(), ...		*/
 
 /*
  * Page fault error code bits:
@@ -225,12 +203,10 @@ static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address)
 	if (!pmd_present(*pmd_k))
 		return NULL;
 
-	if (!pmd_present(*pmd)) {
+	if (!pmd_present(*pmd))
 		set_pmd(pmd, *pmd_k);
-		arch_flush_lazy_mmu_mode();
-	} else {
+	else
 		BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k));
-	}
 
 	return pmd_k;
 }
@@ -538,8 +514,6 @@ bad:
 static int is_errata93(struct pt_regs *regs, unsigned long address)
 {
 #ifdef CONFIG_X86_64
-	static int once;
-
 	if (address != regs->ip)
 		return 0;
 
@@ -549,10 +523,7 @@ static int is_errata93(struct pt_regs *regs, unsigned long address)
 	address |= 0xffffffffUL << 32;
 	if ((address >= (u64)_stext && address <= (u64)_etext) ||
 	    (address >= MODULES_VADDR && address <= MODULES_END)) {
-		if (!once) {
-			printk(errata93_warning);
-			once = 1;
-		}
+		printk_once(errata93_warning);
 		regs->ip = address;
 		return 1;
 	}
@@ -986,6 +957,13 @@ do_page_fault(struct pt_regs *regs, unsigned long error_code)
 	/* Get the faulting address: */
 	address = read_cr2();
 
+	/*
+	 * Detect and handle instructions that would cause a page fault for
+	 * both a tracked kernel page and a userspace page.
+	 */
+	if (kmemcheck_active(regs))
+		kmemcheck_hide(regs);
+
 	if (unlikely(kmmio_fault(regs, address)))
 		return;
 
@@ -1003,9 +981,13 @@ do_page_fault(struct pt_regs *regs, unsigned long error_code)
 	 * protection error (error_code & 9) == 0.
 	 */
 	if (unlikely(fault_in_kernel_space(address))) {
-		if (!(error_code & (PF_RSVD|PF_USER|PF_PROT)) &&
-		    vmalloc_fault(address) >= 0)
-			return;
+		if (!(error_code & (PF_RSVD | PF_USER | PF_PROT))) {
+			if (vmalloc_fault(address) >= 0)
+				return;
+
+			if (kmemcheck_fault(regs, address, error_code))
+				return;
+		}
 
 		/* Can handle a stale RO->RW TLB: */
 		if (spurious_fault(error_code, address))
@@ -1044,6 +1026,8 @@ do_page_fault(struct pt_regs *regs, unsigned long error_code)
 	if (unlikely(error_code & PF_RSVD))
 		pgtable_bad(regs, error_code, address);
 
+	perf_swcounter_event(PERF_COUNT_SW_PAGE_FAULTS, 1, 0, regs, address);
+
 	/*
 	 * If we're in an interrupt, have no user context or are running
 	 * in an atomic region then we must not take the fault:
@@ -1137,10 +1121,15 @@ good_area:
 		return;
 	}
 
-	if (fault & VM_FAULT_MAJOR)
+	if (fault & VM_FAULT_MAJOR) {
 		tsk->maj_flt++;
-	else
+		perf_swcounter_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, 0,
+				     regs, address);
+	} else {
 		tsk->min_flt++;
+		perf_swcounter_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, 0,
+				     regs, address);
+	}
 
 	check_v8086_mode(regs, address, tsk);
 
diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index 8126e8d1a2a4..58f621e81919 100644
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -44,7 +44,6 @@ void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
 	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
 	BUG_ON(!pte_none(*(kmap_pte-idx)));
 	set_pte(kmap_pte-idx, mk_pte(page, prot));
-	arch_flush_lazy_mmu_mode();
 
 	return (void *)vaddr;
 }
@@ -74,7 +73,6 @@ void kunmap_atomic(void *kvaddr, enum km_type type)
 #endif
 	}
 
-	arch_flush_lazy_mmu_mode();
 	pagefault_enable();
 }
 
diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 8f307d914c2e..f46c340727b8 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -26,12 +26,16 @@ static unsigned long page_table_shareable(struct vm_area_struct *svma,
 	unsigned long sbase = saddr & PUD_MASK;
 	unsigned long s_end = sbase + PUD_SIZE;
 
+	/* Allow segments to share if only one is marked locked */
+	unsigned long vm_flags = vma->vm_flags & ~VM_LOCKED;
+	unsigned long svm_flags = svma->vm_flags & ~VM_LOCKED;
+
 	/*
 	 * match the virtual addresses, permission and the alignment of the
 	 * page table page.
 	 */
 	if (pmd_index(addr) != pmd_index(saddr) ||
-	    vma->vm_flags != svma->vm_flags ||
+	    vm_flags != svm_flags ||
 	    sbase < svma->vm_start || svma->vm_end < s_end)
 		return 0;
 
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index ae4f7b5d7104..f53b57e4086f 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -1,3 +1,4 @@
+#include <linux/initrd.h>
 #include <linux/ioport.h>
 #include <linux/swap.h>
 
@@ -10,6 +11,9 @@
 #include <asm/setup.h>
 #include <asm/system.h>
 #include <asm/tlbflush.h>
+#include <asm/tlb.h>
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
 
 unsigned long __initdata e820_table_start;
 unsigned long __meminitdata e820_table_end;
@@ -23,6 +27,69 @@ int direct_gbpages
 #endif
 ;
 
+int nx_enabled;
+
+#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
+static int disable_nx __cpuinitdata;
+
+/*
+ * noexec = on|off
+ *
+ * Control non-executable mappings for processes.
+ *
+ * on      Enable
+ * off     Disable
+ */
+static int __init noexec_setup(char *str)
+{
+	if (!str)
+		return -EINVAL;
+	if (!strncmp(str, "on", 2)) {
+		__supported_pte_mask |= _PAGE_NX;
+		disable_nx = 0;
+	} else if (!strncmp(str, "off", 3)) {
+		disable_nx = 1;
+		__supported_pte_mask &= ~_PAGE_NX;
+	}
+	return 0;
+}
+early_param("noexec", noexec_setup);
+#endif
+
+#ifdef CONFIG_X86_PAE
+static void __init set_nx(void)
+{
+	unsigned int v[4], l, h;
+
+	if (cpu_has_pae && (cpuid_eax(0x80000000) > 0x80000001)) {
+		cpuid(0x80000001, &v[0], &v[1], &v[2], &v[3]);
+
+		if ((v[3] & (1 << 20)) && !disable_nx) {
+			rdmsr(MSR_EFER, l, h);
+			l |= EFER_NX;
+			wrmsr(MSR_EFER, l, h);
+			nx_enabled = 1;
+			__supported_pte_mask |= _PAGE_NX;
+		}
+	}
+}
+#else
+static inline void set_nx(void)
+{
+}
+#endif
+
+#ifdef CONFIG_X86_64
+void __cpuinit check_efer(void)
+{
+	unsigned long efer;
+
+	rdmsrl(MSR_EFER, efer);
+	if (!(efer & EFER_NX) || disable_nx)
+		__supported_pte_mask &= ~_PAGE_NX;
+}
+#endif
+
 static void __init find_early_table_space(unsigned long end, int use_pse,
 					  int use_gbpages)
 {
@@ -66,12 +133,11 @@ static void __init find_early_table_space(unsigned long end, int use_pse,
 	 */
 #ifdef CONFIG_X86_32
 	start = 0x7000;
-	e820_table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT,
-					tables, PAGE_SIZE);
-#else /* CONFIG_X86_64 */
+#else
 	start = 0x8000;
-	e820_table_start = find_e820_area(start, end, tables, PAGE_SIZE);
 #endif
+	e820_table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT,
+					tables, PAGE_SIZE);
 	if (e820_table_start == -1UL)
 		panic("Cannot find space for the kernel page tables");
 
@@ -147,7 +213,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
 	if (!after_bootmem)
 		init_gbpages();
 
-#ifdef CONFIG_DEBUG_PAGEALLOC
+#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KMEMCHECK)
 	/*
 	 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
 	 * This will simplify cpa(), which otherwise needs to support splitting
@@ -159,12 +225,9 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
 	use_gbpages = direct_gbpages;
 #endif
 
-#ifdef CONFIG_X86_32
-#ifdef CONFIG_X86_PAE
 	set_nx();
 	if (nx_enabled)
 		printk(KERN_INFO "NX (Execute Disable) protection: active\n");
-#endif
 
 	/* Enable PSE if available */
 	if (cpu_has_pse)
@@ -175,7 +238,6 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
 		set_in_cr4(X86_CR4_PGE);
 		__supported_pte_mask |= _PAGE_GLOBAL;
 	}
-#endif
 
 	if (use_gbpages)
 		page_size_mask |= 1 << PG_LEVEL_1G;
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 749559ed80f5..3cd7711bb949 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -49,12 +49,9 @@
 #include <asm/paravirt.h>
 #include <asm/setup.h>
 #include <asm/cacheflush.h>
+#include <asm/page_types.h>
 #include <asm/init.h>
 
-unsigned long max_low_pfn_mapped;
-unsigned long max_pfn_mapped;
-
-DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
 unsigned long highstart_pfn, highend_pfn;
 
 static noinline int do_test_wp_bit(void);
@@ -114,7 +111,7 @@ static pte_t * __init one_page_table_init(pmd_t *pmd)
 		pte_t *page_table = NULL;
 
 		if (after_bootmem) {
-#ifdef CONFIG_DEBUG_PAGEALLOC
+#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KMEMCHECK)
 			page_table = (pte_t *) alloc_bootmem_pages(PAGE_SIZE);
 #endif
 			if (!page_table)
@@ -567,7 +564,7 @@ static inline void save_pg_dir(void)
 }
 #endif /* !CONFIG_ACPI_SLEEP */
 
-void zap_low_mappings(void)
+void zap_low_mappings(bool early)
 {
 	int i;
 
@@ -584,64 +581,16 @@ void zap_low_mappings(void)
 		set_pgd(swapper_pg_dir+i, __pgd(0));
 #endif
 	}
-	flush_tlb_all();
-}
 
-int nx_enabled;
+	if (early)
+		__flush_tlb();
+	else
+		flush_tlb_all();
+}
 
 pteval_t __supported_pte_mask __read_mostly = ~(_PAGE_NX | _PAGE_GLOBAL | _PAGE_IOMAP);
 EXPORT_SYMBOL_GPL(__supported_pte_mask);
 
-#ifdef CONFIG_X86_PAE
-
-static int disable_nx __initdata;
-
-/*
- * noexec = on|off
- *
- * Control non executable mappings.
- *
- * on      Enable
- * off     Disable
- */
-static int __init noexec_setup(char *str)
-{
-	if (!str || !strcmp(str, "on")) {
-		if (cpu_has_nx) {
-			__supported_pte_mask |= _PAGE_NX;
-			disable_nx = 0;
-		}
-	} else {
-		if (!strcmp(str, "off")) {
-			disable_nx = 1;
-			__supported_pte_mask &= ~_PAGE_NX;
-		} else {
-			return -EINVAL;
-		}
-	}
-
-	return 0;
-}
-early_param("noexec", noexec_setup);
-
-void __init set_nx(void)
-{
-	unsigned int v[4], l, h;
-
-	if (cpu_has_pae && (cpuid_eax(0x80000000) > 0x80000001)) {
-		cpuid(0x80000001, &v[0], &v[1], &v[2], &v[3]);
-
-		if ((v[3] & (1 << 20)) && !disable_nx) {
-			rdmsr(MSR_EFER, l, h);
-			l |= EFER_NX;
-			wrmsr(MSR_EFER, l, h);
-			nx_enabled = 1;
-			__supported_pte_mask |= _PAGE_NX;
-		}
-	}
-}
-#endif
-
 /* user-defined highmem size */
 static unsigned int highmem_pages = -1;
 
@@ -761,15 +710,15 @@ void __init initmem_init(unsigned long start_pfn,
 	highstart_pfn = highend_pfn = max_pfn;
 	if (max_pfn > max_low_pfn)
 		highstart_pfn = max_low_pfn;
-	memory_present(0, 0, highend_pfn);
 	e820_register_active_regions(0, 0, highend_pfn);
+	sparse_memory_present_with_active_regions(0);
 	printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 		pages_to_mb(highend_pfn - highstart_pfn));
 	num_physpages = highend_pfn;
 	high_memory = (void *) __va(highstart_pfn * PAGE_SIZE - 1) + 1;
 #else
-	memory_present(0, 0, max_low_pfn);
 	e820_register_active_regions(0, 0, max_low_pfn);
+	sparse_memory_present_with_active_regions(0);
 	num_physpages = max_low_pfn;
 	high_memory = (void *) __va(max_low_pfn * PAGE_SIZE - 1) + 1;
 #endif
@@ -1011,7 +960,7 @@ void __init mem_init(void)
 		test_wp_bit();
 
 	save_pg_dir();
-	zap_low_mappings();
+	zap_low_mappings(true);
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 1753e8020df6..9c543290a813 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -50,18 +50,8 @@
 #include <asm/cacheflush.h>
 #include <asm/init.h>
 
-/*
- * end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
- * The direct mapping extends to max_pfn_mapped, so that we can directly access
- * apertures, ACPI and other tables without having to play with fixmaps.
- */
-unsigned long max_low_pfn_mapped;
-unsigned long max_pfn_mapped;
-
 static unsigned long dma_reserve __initdata;
 
-DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
-
 static int __init parse_direct_gbpages_off(char *arg)
 {
 	direct_gbpages = 0;
@@ -85,39 +75,6 @@ early_param("gbpages", parse_direct_gbpages_on);
 pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP;
 EXPORT_SYMBOL_GPL(__supported_pte_mask);
 
-static int disable_nx __cpuinitdata;
-
-/*
- * noexec=on|off
- * Control non-executable mappings for 64-bit processes.
- *
- * on	Enable (default)
- * off	Disable
- */
-static int __init nonx_setup(char *str)
-{
-	if (!str)
-		return -EINVAL;
-	if (!strncmp(str, "on", 2)) {
-		__supported_pte_mask |= _PAGE_NX;
-		disable_nx = 0;
-	} else if (!strncmp(str, "off", 3)) {
-		disable_nx = 1;
-		__supported_pte_mask &= ~_PAGE_NX;
-	}
-	return 0;
-}
-early_param("noexec", nonx_setup);
-
-void __cpuinit check_efer(void)
-{
-	unsigned long efer;
-
-	rdmsrl(MSR_EFER, efer);
-	if (!(efer & EFER_NX) || disable_nx)
-		__supported_pte_mask &= ~_PAGE_NX;
-}
-
 int force_personality32;
 
 /*
@@ -147,7 +104,7 @@ static __ref void *spp_getpage(void)
 	void *ptr;
 
 	if (after_bootmem)
-		ptr = (void *) get_zeroed_page(GFP_ATOMIC);
+		ptr = (void *) get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
 	else
 		ptr = alloc_bootmem_pages(PAGE_SIZE);
 
@@ -324,7 +281,7 @@ static __ref void *alloc_low_page(unsigned long *phys)
 	void *adr;
 
 	if (after_bootmem) {
-		adr = (void *)get_zeroed_page(GFP_ATOMIC);
+		adr = (void *)get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
 		*phys = __pa(adr);
 
 		return adr;
@@ -628,6 +585,7 @@ void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn)
 	early_res_to_bootmem(0, end_pfn<<PAGE_SHIFT);
 	reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT);
 }
+#endif
 
 void __init paging_init(void)
 {
@@ -638,11 +596,10 @@ void __init paging_init(void)
 	max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
 	max_zone_pfns[ZONE_NORMAL] = max_pfn;
 
-	memory_present(0, 0, max_pfn);
+	sparse_memory_present_with_active_regions(MAX_NUMNODES);
 	sparse_init();
 	free_area_init_nodes(max_zone_pfns);
 }
-#endif
 
 /*
  * Memory hotplug specific functions
diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c
index 8056545e2d39..fe6f84ca121e 100644
--- a/arch/x86/mm/iomap_32.c
+++ b/arch/x86/mm/iomap_32.c
@@ -82,7 +82,6 @@ iounmap_atomic(void *kvaddr, enum km_type type)
 	if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx))
 		kpte_clear_flush(kmap_pte-idx, vaddr);
 
-	arch_flush_lazy_mmu_mode();
 	pagefault_enable();
 }
 EXPORT_SYMBOL_GPL(iounmap_atomic);
diff --git a/arch/x86/mm/kmemcheck/Makefile b/arch/x86/mm/kmemcheck/Makefile
new file mode 100644
index 000000000000..520b3bce4095
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/Makefile
@@ -0,0 +1 @@
+obj-y := error.o kmemcheck.o opcode.o pte.o selftest.o shadow.o
diff --git a/arch/x86/mm/kmemcheck/error.c b/arch/x86/mm/kmemcheck/error.c
new file mode 100644
index 000000000000..4901d0dafda6
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/error.c
@@ -0,0 +1,228 @@
+#include <linux/interrupt.h>
+#include <linux/kdebug.h>
+#include <linux/kmemcheck.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/stacktrace.h>
+#include <linux/string.h>
+
+#include "error.h"
+#include "shadow.h"
+
+enum kmemcheck_error_type {
+	KMEMCHECK_ERROR_INVALID_ACCESS,
+	KMEMCHECK_ERROR_BUG,
+};
+
+#define SHADOW_COPY_SIZE (1 << CONFIG_KMEMCHECK_SHADOW_COPY_SHIFT)
+
+struct kmemcheck_error {
+	enum kmemcheck_error_type type;
+
+	union {
+		/* KMEMCHECK_ERROR_INVALID_ACCESS */
+		struct {
+			/* Kind of access that caused the error */
+			enum kmemcheck_shadow state;
+			/* Address and size of the erroneous read */
+			unsigned long	address;
+			unsigned int	size;
+		};
+	};
+
+	struct pt_regs		regs;
+	struct stack_trace	trace;
+	unsigned long		trace_entries[32];
+
+	/* We compress it to a char. */
+	unsigned char		shadow_copy[SHADOW_COPY_SIZE];
+	unsigned char		memory_copy[SHADOW_COPY_SIZE];
+};
+
+/*
+ * Create a ring queue of errors to output. We can't call printk() directly
+ * from the kmemcheck traps, since this may call the console drivers and
+ * result in a recursive fault.
+ */
+static struct kmemcheck_error error_fifo[CONFIG_KMEMCHECK_QUEUE_SIZE];
+static unsigned int error_count;
+static unsigned int error_rd;
+static unsigned int error_wr;
+static unsigned int error_missed_count;
+
+static struct kmemcheck_error *error_next_wr(void)
+{
+	struct kmemcheck_error *e;
+
+	if (error_count == ARRAY_SIZE(error_fifo)) {
+		++error_missed_count;
+		return NULL;
+	}
+
+	e = &error_fifo[error_wr];
+	if (++error_wr == ARRAY_SIZE(error_fifo))
+		error_wr = 0;
+	++error_count;
+	return e;
+}
+
+static struct kmemcheck_error *error_next_rd(void)
+{
+	struct kmemcheck_error *e;
+
+	if (error_count == 0)
+		return NULL;
+
+	e = &error_fifo[error_rd];
+	if (++error_rd == ARRAY_SIZE(error_fifo))
+		error_rd = 0;
+	--error_count;
+	return e;
+}
+
+void kmemcheck_error_recall(void)
+{
+	static const char *desc[] = {
+		[KMEMCHECK_SHADOW_UNALLOCATED]		= "unallocated",
+		[KMEMCHECK_SHADOW_UNINITIALIZED]	= "uninitialized",
+		[KMEMCHECK_SHADOW_INITIALIZED]		= "initialized",
+		[KMEMCHECK_SHADOW_FREED]		= "freed",
+	};
+
+	static const char short_desc[] = {
+		[KMEMCHECK_SHADOW_UNALLOCATED]		= 'a',
+		[KMEMCHECK_SHADOW_UNINITIALIZED]	= 'u',
+		[KMEMCHECK_SHADOW_INITIALIZED]		= 'i',
+		[KMEMCHECK_SHADOW_FREED]		= 'f',
+	};
+
+	struct kmemcheck_error *e;
+	unsigned int i;
+
+	e = error_next_rd();
+	if (!e)
+		return;
+
+	switch (e->type) {
+	case KMEMCHECK_ERROR_INVALID_ACCESS:
+		printk(KERN_ERR  "WARNING: kmemcheck: Caught %d-bit read "
+			"from %s memory (%p)\n",
+			8 * e->size, e->state < ARRAY_SIZE(desc) ?
+				desc[e->state] : "(invalid shadow state)",
+			(void *) e->address);
+
+		printk(KERN_INFO);
+		for (i = 0; i < SHADOW_COPY_SIZE; ++i)
+			printk("%02x", e->memory_copy[i]);
+		printk("\n");
+
+		printk(KERN_INFO);
+		for (i = 0; i < SHADOW_COPY_SIZE; ++i) {
+			if (e->shadow_copy[i] < ARRAY_SIZE(short_desc))
+				printk(" %c", short_desc[e->shadow_copy[i]]);
+			else
+				printk(" ?");
+		}
+		printk("\n");
+		printk(KERN_INFO "%*c\n", 2 + 2
+			* (int) (e->address & (SHADOW_COPY_SIZE - 1)), '^');
+		break;
+	case KMEMCHECK_ERROR_BUG:
+		printk(KERN_EMERG "ERROR: kmemcheck: Fatal error\n");
+		break;
+	}
+
+	__show_regs(&e->regs, 1);
+	print_stack_trace(&e->trace, 0);
+}
+
+static void do_wakeup(unsigned long data)
+{
+	while (error_count > 0)
+		kmemcheck_error_recall();
+
+	if (error_missed_count > 0) {
+		printk(KERN_WARNING "kmemcheck: Lost %d error reports because "
+			"the queue was too small\n", error_missed_count);
+		error_missed_count = 0;
+	}
+}
+
+static DECLARE_TASKLET(kmemcheck_tasklet, &do_wakeup, 0);
+
+/*
+ * Save the context of an error report.
+ */
+void kmemcheck_error_save(enum kmemcheck_shadow state,
+	unsigned long address, unsigned int size, struct pt_regs *regs)
+{
+	static unsigned long prev_ip;
+
+	struct kmemcheck_error *e;
+	void *shadow_copy;
+	void *memory_copy;
+
+	/* Don't report several adjacent errors from the same EIP. */
+	if (regs->ip == prev_ip)
+		return;
+	prev_ip = regs->ip;
+
+	e = error_next_wr();
+	if (!e)
+		return;
+
+	e->type = KMEMCHECK_ERROR_INVALID_ACCESS;
+
+	e->state = state;
+	e->address = address;
+	e->size = size;
+
+	/* Save regs */
+	memcpy(&e->regs, regs, sizeof(*regs));
+
+	/* Save stack trace */
+	e->trace.nr_entries = 0;
+	e->trace.entries = e->trace_entries;
+	e->trace.max_entries = ARRAY_SIZE(e->trace_entries);
+	e->trace.skip = 0;
+	save_stack_trace_bp(&e->trace, regs->bp);
+
+	/* Round address down to nearest 16 bytes */
+	shadow_copy = kmemcheck_shadow_lookup(address
+		& ~(SHADOW_COPY_SIZE - 1));
+	BUG_ON(!shadow_copy);
+
+	memcpy(e->shadow_copy, shadow_copy, SHADOW_COPY_SIZE);
+
+	kmemcheck_show_addr(address);
+	memory_copy = (void *) (address & ~(SHADOW_COPY_SIZE - 1));
+	memcpy(e->memory_copy, memory_copy, SHADOW_COPY_SIZE);
+	kmemcheck_hide_addr(address);
+
+	tasklet_hi_schedule_first(&kmemcheck_tasklet);
+}
+
+/*
+ * Save the context of a kmemcheck bug.
+ */
+void kmemcheck_error_save_bug(struct pt_regs *regs)
+{
+	struct kmemcheck_error *e;
+
+	e = error_next_wr();
+	if (!e)
+		return;
+
+	e->type = KMEMCHECK_ERROR_BUG;
+
+	memcpy(&e->regs, regs, sizeof(*regs));
+
+	e->trace.nr_entries = 0;
+	e->trace.entries = e->trace_entries;
+	e->trace.max_entries = ARRAY_SIZE(e->trace_entries);
+	e->trace.skip = 1;
+	save_stack_trace(&e->trace);
+
+	tasklet_hi_schedule_first(&kmemcheck_tasklet);
+}
diff --git a/arch/x86/mm/kmemcheck/error.h b/arch/x86/mm/kmemcheck/error.h
new file mode 100644
index 000000000000..0efc2e8d0a20
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/error.h
@@ -0,0 +1,15 @@
+#ifndef ARCH__X86__MM__KMEMCHECK__ERROR_H
+#define ARCH__X86__MM__KMEMCHECK__ERROR_H
+
+#include <linux/ptrace.h>
+
+#include "shadow.h"
+
+void kmemcheck_error_save(enum kmemcheck_shadow state,
+	unsigned long address, unsigned int size, struct pt_regs *regs);
+
+void kmemcheck_error_save_bug(struct pt_regs *regs);
+
+void kmemcheck_error_recall(void);
+
+#endif
diff --git a/arch/x86/mm/kmemcheck/kmemcheck.c b/arch/x86/mm/kmemcheck/kmemcheck.c
new file mode 100644
index 000000000000..2c55ed098654
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/kmemcheck.c
@@ -0,0 +1,640 @@
+/**
+ * kmemcheck - a heavyweight memory checker for the linux kernel
+ * Copyright (C) 2007, 2008  Vegard Nossum <vegardno@ifi.uio.no>
+ * (With a lot of help from Ingo Molnar and Pekka Enberg.)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2) as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kallsyms.h>
+#include <linux/kernel.h>
+#include <linux/kmemcheck.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/page-flags.h>
+#include <linux/percpu.h>
+#include <linux/ptrace.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include <asm/cacheflush.h>
+#include <asm/kmemcheck.h>
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+
+#include "error.h"
+#include "opcode.h"
+#include "pte.h"
+#include "selftest.h"
+#include "shadow.h"
+
+
+#ifdef CONFIG_KMEMCHECK_DISABLED_BY_DEFAULT
+#  define KMEMCHECK_ENABLED 0
+#endif
+
+#ifdef CONFIG_KMEMCHECK_ENABLED_BY_DEFAULT
+#  define KMEMCHECK_ENABLED 1
+#endif
+
+#ifdef CONFIG_KMEMCHECK_ONESHOT_BY_DEFAULT
+#  define KMEMCHECK_ENABLED 2
+#endif
+
+int kmemcheck_enabled = KMEMCHECK_ENABLED;
+
+int __init kmemcheck_init(void)
+{
+#ifdef CONFIG_SMP
+	/*
+	 * Limit SMP to use a single CPU. We rely on the fact that this code
+	 * runs before SMP is set up.
+	 */
+	if (setup_max_cpus > 1) {
+		printk(KERN_INFO
+			"kmemcheck: Limiting number of CPUs to 1.\n");
+		setup_max_cpus = 1;
+	}
+#endif
+
+	if (!kmemcheck_selftest()) {
+		printk(KERN_INFO "kmemcheck: self-tests failed; disabling\n");
+		kmemcheck_enabled = 0;
+		return -EINVAL;
+	}
+
+	printk(KERN_INFO "kmemcheck: Initialized\n");
+	return 0;
+}
+
+early_initcall(kmemcheck_init);
+
+/*
+ * We need to parse the kmemcheck= option before any memory is allocated.
+ */
+static int __init param_kmemcheck(char *str)
+{
+	if (!str)
+		return -EINVAL;
+
+	sscanf(str, "%d", &kmemcheck_enabled);
+	return 0;
+}
+
+early_param("kmemcheck", param_kmemcheck);
+
+int kmemcheck_show_addr(unsigned long address)
+{
+	pte_t *pte;
+
+	pte = kmemcheck_pte_lookup(address);
+	if (!pte)
+		return 0;
+
+	set_pte(pte, __pte(pte_val(*pte) | _PAGE_PRESENT));
+	__flush_tlb_one(address);
+	return 1;
+}
+
+int kmemcheck_hide_addr(unsigned long address)
+{
+	pte_t *pte;
+
+	pte = kmemcheck_pte_lookup(address);
+	if (!pte)
+		return 0;
+
+	set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_PRESENT));
+	__flush_tlb_one(address);
+	return 1;
+}
+
+struct kmemcheck_context {
+	bool busy;
+	int balance;
+
+	/*
+	 * There can be at most two memory operands to an instruction, but
+	 * each address can cross a page boundary -- so we may need up to
+	 * four addresses that must be hidden/revealed for each fault.
+	 */
+	unsigned long addr[4];
+	unsigned long n_addrs;
+	unsigned long flags;
+
+	/* Data size of the instruction that caused a fault. */
+	unsigned int size;
+};
+
+static DEFINE_PER_CPU(struct kmemcheck_context, kmemcheck_context);
+
+bool kmemcheck_active(struct pt_regs *regs)
+{
+	struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
+
+	return data->balance > 0;
+}
+
+/* Save an address that needs to be shown/hidden */
+static void kmemcheck_save_addr(unsigned long addr)
+{
+	struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
+
+	BUG_ON(data->n_addrs >= ARRAY_SIZE(data->addr));
+	data->addr[data->n_addrs++] = addr;
+}
+
+static unsigned int kmemcheck_show_all(void)
+{
+	struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
+	unsigned int i;
+	unsigned int n;
+
+	n = 0;
+	for (i = 0; i < data->n_addrs; ++i)
+		n += kmemcheck_show_addr(data->addr[i]);
+
+	return n;
+}
+
+static unsigned int kmemcheck_hide_all(void)
+{
+	struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
+	unsigned int i;
+	unsigned int n;
+
+	n = 0;
+	for (i = 0; i < data->n_addrs; ++i)
+		n += kmemcheck_hide_addr(data->addr[i]);
+
+	return n;
+}
+
+/*
+ * Called from the #PF handler.
+ */
+void kmemcheck_show(struct pt_regs *regs)
+{
+	struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
+
+	BUG_ON(!irqs_disabled());
+
+	if (unlikely(data->balance != 0)) {
+		kmemcheck_show_all();
+		kmemcheck_error_save_bug(regs);
+		data->balance = 0;
+		return;
+	}
+
+	/*
+	 * None of the addresses actually belonged to kmemcheck. Note that
+	 * this is not an error.
+	 */
+	if (kmemcheck_show_all() == 0)
+		return;
+
+	++data->balance;
+
+	/*
+	 * The IF needs to be cleared as well, so that the faulting
+	 * instruction can run "uninterrupted". Otherwise, we might take
+	 * an interrupt and start executing that before we've had a chance
+	 * to hide the page again.
+	 *
+	 * NOTE: In the rare case of multiple faults, we must not override
+	 * the original flags:
+	 */
+	if (!(regs->flags & X86_EFLAGS_TF))
+		data->flags = regs->flags;
+
+	regs->flags |= X86_EFLAGS_TF;
+	regs->flags &= ~X86_EFLAGS_IF;
+}
+
+/*
+ * Called from the #DB handler.
+ */
+void kmemcheck_hide(struct pt_regs *regs)
+{
+	struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
+	int n;
+
+	BUG_ON(!irqs_disabled());
+
+	if (data->balance == 0)
+		return;
+
+	if (unlikely(data->balance != 1)) {
+		kmemcheck_show_all();
+		kmemcheck_error_save_bug(regs);
+		data->n_addrs = 0;
+		data->balance = 0;
+
+		if (!(data->flags & X86_EFLAGS_TF))
+			regs->flags &= ~X86_EFLAGS_TF;
+		if (data->flags & X86_EFLAGS_IF)
+			regs->flags |= X86_EFLAGS_IF;
+		return;
+	}
+
+	if (kmemcheck_enabled)
+		n = kmemcheck_hide_all();
+	else
+		n = kmemcheck_show_all();
+
+	if (n == 0)
+		return;
+
+	--data->balance;
+
+	data->n_addrs = 0;
+
+	if (!(data->flags & X86_EFLAGS_TF))
+		regs->flags &= ~X86_EFLAGS_TF;
+	if (data->flags & X86_EFLAGS_IF)
+		regs->flags |= X86_EFLAGS_IF;
+}
+
+void kmemcheck_show_pages(struct page *p, unsigned int n)
+{
+	unsigned int i;
+
+	for (i = 0; i < n; ++i) {
+		unsigned long address;
+		pte_t *pte;
+		unsigned int level;
+
+		address = (unsigned long) page_address(&p[i]);
+		pte = lookup_address(address, &level);
+		BUG_ON(!pte);
+		BUG_ON(level != PG_LEVEL_4K);
+
+		set_pte(pte, __pte(pte_val(*pte) | _PAGE_PRESENT));
+		set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_HIDDEN));
+		__flush_tlb_one(address);
+	}
+}
+
+bool kmemcheck_page_is_tracked(struct page *p)
+{
+	/* This will also check the "hidden" flag of the PTE. */
+	return kmemcheck_pte_lookup((unsigned long) page_address(p));
+}
+
+void kmemcheck_hide_pages(struct page *p, unsigned int n)
+{
+	unsigned int i;
+
+	for (i = 0; i < n; ++i) {
+		unsigned long address;
+		pte_t *pte;
+		unsigned int level;
+
+		address = (unsigned long) page_address(&p[i]);
+		pte = lookup_address(address, &level);
+		BUG_ON(!pte);
+		BUG_ON(level != PG_LEVEL_4K);
+
+		set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_PRESENT));
+		set_pte(pte, __pte(pte_val(*pte) | _PAGE_HIDDEN));
+		__flush_tlb_one(address);
+	}
+}
+
+/* Access may NOT cross page boundary */
+static void kmemcheck_read_strict(struct pt_regs *regs,
+	unsigned long addr, unsigned int size)
+{
+	void *shadow;
+	enum kmemcheck_shadow status;
+
+	shadow = kmemcheck_shadow_lookup(addr);
+	if (!shadow)
+		return;
+
+	kmemcheck_save_addr(addr);
+	status = kmemcheck_shadow_test(shadow, size);
+	if (status == KMEMCHECK_SHADOW_INITIALIZED)
+		return;
+
+	if (kmemcheck_enabled)
+		kmemcheck_error_save(status, addr, size, regs);
+
+	if (kmemcheck_enabled == 2)
+		kmemcheck_enabled = 0;
+
+	/* Don't warn about it again. */
+	kmemcheck_shadow_set(shadow, size);
+}
+
+/* Access may cross page boundary */
+static void kmemcheck_read(struct pt_regs *regs,
+	unsigned long addr, unsigned int size)
+{
+	unsigned long page = addr & PAGE_MASK;
+	unsigned long next_addr = addr + size - 1;
+	unsigned long next_page = next_addr & PAGE_MASK;
+
+	if (likely(page == next_page)) {
+		kmemcheck_read_strict(regs, addr, size);
+		return;
+	}
+
+	/*
+	 * What we do is basically to split the access across the
+	 * two pages and handle each part separately. Yes, this means
+	 * that we may now see reads that are 3 + 5 bytes, for
+	 * example (and if both are uninitialized, there will be two
+	 * reports), but it makes the code a lot simpler.
+	 */
+	kmemcheck_read_strict(regs, addr, next_page - addr);
+	kmemcheck_read_strict(regs, next_page, next_addr - next_page);
+}
+
+static void kmemcheck_write_strict(struct pt_regs *regs,
+	unsigned long addr, unsigned int size)
+{
+	void *shadow;
+
+	shadow = kmemcheck_shadow_lookup(addr);
+	if (!shadow)
+		return;
+
+	kmemcheck_save_addr(addr);
+	kmemcheck_shadow_set(shadow, size);
+}
+
+static void kmemcheck_write(struct pt_regs *regs,
+	unsigned long addr, unsigned int size)
+{
+	unsigned long page = addr & PAGE_MASK;
+	unsigned long next_addr = addr + size - 1;
+	unsigned long next_page = next_addr & PAGE_MASK;
+
+	if (likely(page == next_page)) {
+		kmemcheck_write_strict(regs, addr, size);
+		return;
+	}
+
+	/* See comment in kmemcheck_read(). */
+	kmemcheck_write_strict(regs, addr, next_page - addr);
+	kmemcheck_write_strict(regs, next_page, next_addr - next_page);
+}
+
+/*
+ * Copying is hard. We have two addresses, each of which may be split across
+ * a page (and each page will have different shadow addresses).
+ */
+static void kmemcheck_copy(struct pt_regs *regs,
+	unsigned long src_addr, unsigned long dst_addr, unsigned int size)
+{
+	uint8_t shadow[8];
+	enum kmemcheck_shadow status;
+
+	unsigned long page;
+	unsigned long next_addr;
+	unsigned long next_page;
+
+	uint8_t *x;
+	unsigned int i;
+	unsigned int n;
+
+	BUG_ON(size > sizeof(shadow));
+
+	page = src_addr & PAGE_MASK;
+	next_addr = src_addr + size - 1;
+	next_page = next_addr & PAGE_MASK;
+
+	if (likely(page == next_page)) {
+		/* Same page */
+		x = kmemcheck_shadow_lookup(src_addr);
+		if (x) {
+			kmemcheck_save_addr(src_addr);
+			for (i = 0; i < size; ++i)
+				shadow[i] = x[i];
+		} else {
+			for (i = 0; i < size; ++i)
+				shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
+		}
+	} else {
+		n = next_page - src_addr;
+		BUG_ON(n > sizeof(shadow));
+
+		/* First page */
+		x = kmemcheck_shadow_lookup(src_addr);
+		if (x) {
+			kmemcheck_save_addr(src_addr);
+			for (i = 0; i < n; ++i)
+				shadow[i] = x[i];
+		} else {
+			/* Not tracked */
+			for (i = 0; i < n; ++i)
+				shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
+		}
+
+		/* Second page */
+		x = kmemcheck_shadow_lookup(next_page);
+		if (x) {
+			kmemcheck_save_addr(next_page);
+			for (i = n; i < size; ++i)
+				shadow[i] = x[i - n];
+		} else {
+			/* Not tracked */
+			for (i = n; i < size; ++i)
+				shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
+		}
+	}
+
+	page = dst_addr & PAGE_MASK;
+	next_addr = dst_addr + size - 1;
+	next_page = next_addr & PAGE_MASK;
+
+	if (likely(page == next_page)) {
+		/* Same page */
+		x = kmemcheck_shadow_lookup(dst_addr);
+		if (x) {
+			kmemcheck_save_addr(dst_addr);
+			for (i = 0; i < size; ++i) {
+				x[i] = shadow[i];
+				shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
+			}
+		}
+	} else {
+		n = next_page - dst_addr;
+		BUG_ON(n > sizeof(shadow));
+
+		/* First page */
+		x = kmemcheck_shadow_lookup(dst_addr);
+		if (x) {
+			kmemcheck_save_addr(dst_addr);
+			for (i = 0; i < n; ++i) {
+				x[i] = shadow[i];
+				shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
+			}
+		}
+
+		/* Second page */
+		x = kmemcheck_shadow_lookup(next_page);
+		if (x) {
+			kmemcheck_save_addr(next_page);
+			for (i = n; i < size; ++i) {
+				x[i - n] = shadow[i];
+				shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
+			}
+		}
+	}
+
+	status = kmemcheck_shadow_test(shadow, size);
+	if (status == KMEMCHECK_SHADOW_INITIALIZED)
+		return;
+
+	if (kmemcheck_enabled)
+		kmemcheck_error_save(status, src_addr, size, regs);
+
+	if (kmemcheck_enabled == 2)
+		kmemcheck_enabled = 0;
+}
+
+enum kmemcheck_method {
+	KMEMCHECK_READ,
+	KMEMCHECK_WRITE,
+};
+
+static void kmemcheck_access(struct pt_regs *regs,
+	unsigned long fallback_address, enum kmemcheck_method fallback_method)
+{
+	const uint8_t *insn;
+	const uint8_t *insn_primary;
+	unsigned int size;
+
+	struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
+
+	/* Recursive fault -- ouch. */
+	if (data->busy) {
+		kmemcheck_show_addr(fallback_address);
+		kmemcheck_error_save_bug(regs);
+		return;
+	}
+
+	data->busy = true;
+
+	insn = (const uint8_t *) regs->ip;
+	insn_primary = kmemcheck_opcode_get_primary(insn);
+
+	kmemcheck_opcode_decode(insn, &size);
+
+	switch (insn_primary[0]) {
+#ifdef CONFIG_KMEMCHECK_BITOPS_OK
+		/* AND, OR, XOR */
+		/*
+		 * Unfortunately, these instructions have to be excluded from
+		 * our regular checking since they access only some (and not
+		 * all) bits. This clears out "bogus" bitfield-access warnings.
+		 */
+	case 0x80:
+	case 0x81:
+	case 0x82:
+	case 0x83:
+		switch ((insn_primary[1] >> 3) & 7) {
+			/* OR */
+		case 1:
+			/* AND */
+		case 4:
+			/* XOR */
+		case 6:
+			kmemcheck_write(regs, fallback_address, size);
+			goto out;
+
+			/* ADD */
+		case 0:
+			/* ADC */
+		case 2:
+			/* SBB */
+		case 3:
+			/* SUB */
+		case 5:
+			/* CMP */
+		case 7:
+			break;
+		}
+		break;
+#endif
+
+		/* MOVS, MOVSB, MOVSW, MOVSD */
+	case 0xa4:
+	case 0xa5:
+		/*
+		 * These instructions are special because they take two
+		 * addresses, but we only get one page fault.
+		 */
+		kmemcheck_copy(regs, regs->si, regs->di, size);
+		goto out;
+
+		/* CMPS, CMPSB, CMPSW, CMPSD */
+	case 0xa6:
+	case 0xa7:
+		kmemcheck_read(regs, regs->si, size);
+		kmemcheck_read(regs, regs->di, size);
+		goto out;
+	}
+
+	/*
+	 * If the opcode isn't special in any way, we use the data from the
+	 * page fault handler to determine the address and type of memory
+	 * access.
+	 */
+	switch (fallback_method) {
+	case KMEMCHECK_READ:
+		kmemcheck_read(regs, fallback_address, size);
+		goto out;
+	case KMEMCHECK_WRITE:
+		kmemcheck_write(regs, fallback_address, size);
+		goto out;
+	}
+
+out:
+	data->busy = false;
+}
+
+bool kmemcheck_fault(struct pt_regs *regs, unsigned long address,
+	unsigned long error_code)
+{
+	pte_t *pte;
+
+	/*
+	 * XXX: Is it safe to assume that memory accesses from virtual 86
+	 * mode or non-kernel code segments will _never_ access kernel
+	 * memory (e.g. tracked pages)? For now, we need this to avoid
+	 * invoking kmemcheck for PnP BIOS calls.
+	 */
+	if (regs->flags & X86_VM_MASK)
+		return false;
+	if (regs->cs != __KERNEL_CS)
+		return false;
+
+	pte = kmemcheck_pte_lookup(address);
+	if (!pte)
+		return false;
+
+	if (error_code & 2)
+		kmemcheck_access(regs, address, KMEMCHECK_WRITE);
+	else
+		kmemcheck_access(regs, address, KMEMCHECK_READ);
+
+	kmemcheck_show(regs);
+	return true;
+}
+
+bool kmemcheck_trap(struct pt_regs *regs)
+{
+	if (!kmemcheck_active(regs))
+		return false;
+
+	/* We're done. */
+	kmemcheck_hide(regs);
+	return true;
+}
diff --git a/arch/x86/mm/kmemcheck/opcode.c b/arch/x86/mm/kmemcheck/opcode.c
new file mode 100644
index 000000000000..63c19e27aa6f
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/opcode.c
@@ -0,0 +1,106 @@
+#include <linux/types.h>
+
+#include "opcode.h"
+
+static bool opcode_is_prefix(uint8_t b)
+{
+	return
+		/* Group 1 */
+		b == 0xf0 || b == 0xf2 || b == 0xf3
+		/* Group 2 */
+		|| b == 0x2e || b == 0x36 || b == 0x3e || b == 0x26
+		|| b == 0x64 || b == 0x65 || b == 0x2e || b == 0x3e
+		/* Group 3 */
+		|| b == 0x66
+		/* Group 4 */
+		|| b == 0x67;
+}
+
+#ifdef CONFIG_X86_64
+static bool opcode_is_rex_prefix(uint8_t b)
+{
+	return (b & 0xf0) == 0x40;
+}
+#else
+static bool opcode_is_rex_prefix(uint8_t b)
+{
+	return false;
+}
+#endif
+
+#define REX_W (1 << 3)
+
+/*
+ * This is a VERY crude opcode decoder. We only need to find the size of the
+ * load/store that caused our #PF and this should work for all the opcodes
+ * that we care about. Moreover, the ones who invented this instruction set
+ * should be shot.
+ */
+void kmemcheck_opcode_decode(const uint8_t *op, unsigned int *size)
+{
+	/* Default operand size */
+	int operand_size_override = 4;
+
+	/* prefixes */
+	for (; opcode_is_prefix(*op); ++op) {
+		if (*op == 0x66)
+			operand_size_override = 2;
+	}
+
+	/* REX prefix */
+	if (opcode_is_rex_prefix(*op)) {
+		uint8_t rex = *op;
+
+		++op;
+		if (rex & REX_W) {
+			switch (*op) {
+			case 0x63:
+				*size = 4;
+				return;
+			case 0x0f:
+				++op;
+
+				switch (*op) {
+				case 0xb6:
+				case 0xbe:
+					*size = 1;
+					return;
+				case 0xb7:
+				case 0xbf:
+					*size = 2;
+					return;
+				}
+
+				break;
+			}
+
+			*size = 8;
+			return;
+		}
+	}
+
+	/* escape opcode */
+	if (*op == 0x0f) {
+		++op;
+
+		/*
+		 * This is move with zero-extend and sign-extend, respectively;
+		 * we don't have to think about 0xb6/0xbe, because this is
+		 * already handled in the conditional below.
+		 */
+		if (*op == 0xb7 || *op == 0xbf)
+			operand_size_override = 2;
+	}
+
+	*size = (*op & 1) ? operand_size_override : 1;
+}
+
+const uint8_t *kmemcheck_opcode_get_primary(const uint8_t *op)
+{
+	/* skip prefixes */
+	while (opcode_is_prefix(*op))
+		++op;
+	if (opcode_is_rex_prefix(*op))
+		++op;
+	return op;
+}
diff --git a/arch/x86/mm/kmemcheck/opcode.h b/arch/x86/mm/kmemcheck/opcode.h
new file mode 100644
index 000000000000..6956aad66b5b
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/opcode.h
@@ -0,0 +1,9 @@
+#ifndef ARCH__X86__MM__KMEMCHECK__OPCODE_H
+#define ARCH__X86__MM__KMEMCHECK__OPCODE_H
+
+#include <linux/types.h>
+
+void kmemcheck_opcode_decode(const uint8_t *op, unsigned int *size);
+const uint8_t *kmemcheck_opcode_get_primary(const uint8_t *op);
+
+#endif
diff --git a/arch/x86/mm/kmemcheck/pte.c b/arch/x86/mm/kmemcheck/pte.c
new file mode 100644
index 000000000000..4ead26eeaf96
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/pte.c
@@ -0,0 +1,22 @@
+#include <linux/mm.h>
+
+#include <asm/pgtable.h>
+
+#include "pte.h"
+
+pte_t *kmemcheck_pte_lookup(unsigned long address)
+{
+	pte_t *pte;
+	unsigned int level;
+
+	pte = lookup_address(address, &level);
+	if (!pte)
+		return NULL;
+	if (level != PG_LEVEL_4K)
+		return NULL;
+	if (!pte_hidden(*pte))
+		return NULL;
+
+	return pte;
+}
+
diff --git a/arch/x86/mm/kmemcheck/pte.h b/arch/x86/mm/kmemcheck/pte.h
new file mode 100644
index 000000000000..9f5966456492
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/pte.h
@@ -0,0 +1,10 @@
+#ifndef ARCH__X86__MM__KMEMCHECK__PTE_H
+#define ARCH__X86__MM__KMEMCHECK__PTE_H
+
+#include <linux/mm.h>
+
+#include <asm/pgtable.h>
+
+pte_t *kmemcheck_pte_lookup(unsigned long address);
+
+#endif
diff --git a/arch/x86/mm/kmemcheck/selftest.c b/arch/x86/mm/kmemcheck/selftest.c
new file mode 100644
index 000000000000..036efbea8b28
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/selftest.c
@@ -0,0 +1,69 @@
+#include <linux/kernel.h>
+
+#include "opcode.h"
+#include "selftest.h"
+
+struct selftest_opcode {
+	unsigned int expected_size;
+	const uint8_t *insn;
+	const char *desc;
+};
+
+static const struct selftest_opcode selftest_opcodes[] = {
+	/* REP MOVS */
+	{1, "\xf3\xa4", 		"rep movsb <mem8>, <mem8>"},
+	{4, "\xf3\xa5",			"rep movsl <mem32>, <mem32>"},
+
+	/* MOVZX / MOVZXD */
+	{1, "\x66\x0f\xb6\x51\xf8",	"movzwq <mem8>, <reg16>"},
+	{1, "\x0f\xb6\x51\xf8",		"movzwq <mem8>, <reg32>"},
+
+	/* MOVSX / MOVSXD */
+	{1, "\x66\x0f\xbe\x51\xf8",	"movswq <mem8>, <reg16>"},
+	{1, "\x0f\xbe\x51\xf8",		"movswq <mem8>, <reg32>"},
+
+#ifdef CONFIG_X86_64
+	/* MOVZX / MOVZXD */
+	{1, "\x49\x0f\xb6\x51\xf8",	"movzbq <mem8>, <reg64>"},
+	{2, "\x49\x0f\xb7\x51\xf8",	"movzbq <mem16>, <reg64>"},
+
+	/* MOVSX / MOVSXD */
+	{1, "\x49\x0f\xbe\x51\xf8",	"movsbq <mem8>, <reg64>"},
+	{2, "\x49\x0f\xbf\x51\xf8",	"movsbq <mem16>, <reg64>"},
+	{4, "\x49\x63\x51\xf8",		"movslq <mem32>, <reg64>"},
+#endif
+};
+
+static bool selftest_opcode_one(const struct selftest_opcode *op)
+{
+	unsigned size;
+
+	kmemcheck_opcode_decode(op->insn, &size);
+
+	if (size == op->expected_size)
+		return true;
+
+	printk(KERN_WARNING "kmemcheck: opcode %s: expected size %d, got %d\n",
+		op->desc, op->expected_size, size);
+	return false;
+}
+
+static bool selftest_opcodes_all(void)
+{
+	bool pass = true;
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(selftest_opcodes); ++i)
+		pass = pass && selftest_opcode_one(&selftest_opcodes[i]);
+
+	return pass;
+}
+
+bool kmemcheck_selftest(void)
+{
+	bool pass = true;
+
+	pass = pass && selftest_opcodes_all();
+
+	return pass;
+}
diff --git a/arch/x86/mm/kmemcheck/selftest.h b/arch/x86/mm/kmemcheck/selftest.h
new file mode 100644
index 000000000000..8fed4fe11f95
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/selftest.h
@@ -0,0 +1,6 @@
+#ifndef ARCH_X86_MM_KMEMCHECK_SELFTEST_H
+#define ARCH_X86_MM_KMEMCHECK_SELFTEST_H
+
+bool kmemcheck_selftest(void);
+
+#endif
diff --git a/arch/x86/mm/kmemcheck/shadow.c b/arch/x86/mm/kmemcheck/shadow.c
new file mode 100644
index 000000000000..e773b6bd0079
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/shadow.c
@@ -0,0 +1,162 @@
+#include <linux/kmemcheck.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+
+#include "pte.h"
+#include "shadow.h"
+
+/*
+ * Return the shadow address for the given address. Returns NULL if the
+ * address is not tracked.
+ *
+ * We need to be extremely careful not to follow any invalid pointers,
+ * because this function can be called for *any* possible address.
+ */
+void *kmemcheck_shadow_lookup(unsigned long address)
+{
+	pte_t *pte;
+	struct page *page;
+
+	if (!virt_addr_valid(address))
+		return NULL;
+
+	pte = kmemcheck_pte_lookup(address);
+	if (!pte)
+		return NULL;
+
+	page = virt_to_page(address);
+	if (!page->shadow)
+		return NULL;
+	return page->shadow + (address & (PAGE_SIZE - 1));
+}
+
+static void mark_shadow(void *address, unsigned int n,
+	enum kmemcheck_shadow status)
+{
+	unsigned long addr = (unsigned long) address;
+	unsigned long last_addr = addr + n - 1;
+	unsigned long page = addr & PAGE_MASK;
+	unsigned long last_page = last_addr & PAGE_MASK;
+	unsigned int first_n;
+	void *shadow;
+
+	/* If the memory range crosses a page boundary, stop there. */
+	if (page == last_page)
+		first_n = n;
+	else
+		first_n = page + PAGE_SIZE - addr;
+
+	shadow = kmemcheck_shadow_lookup(addr);
+	if (shadow)
+		memset(shadow, status, first_n);
+
+	addr += first_n;
+	n -= first_n;
+
+	/* Do full-page memset()s. */
+	while (n >= PAGE_SIZE) {
+		shadow = kmemcheck_shadow_lookup(addr);
+		if (shadow)
+			memset(shadow, status, PAGE_SIZE);
+
+		addr += PAGE_SIZE;
+		n -= PAGE_SIZE;
+	}
+
+	/* Do the remaining page, if any. */
+	if (n > 0) {
+		shadow = kmemcheck_shadow_lookup(addr);
+		if (shadow)
+			memset(shadow, status, n);
+	}
+}
+
+void kmemcheck_mark_unallocated(void *address, unsigned int n)
+{
+	mark_shadow(address, n, KMEMCHECK_SHADOW_UNALLOCATED);
+}
+
+void kmemcheck_mark_uninitialized(void *address, unsigned int n)
+{
+	mark_shadow(address, n, KMEMCHECK_SHADOW_UNINITIALIZED);
+}
+
+/*
+ * Fill the shadow memory of the given address such that the memory at that
+ * address is marked as being initialized.
+ */
+void kmemcheck_mark_initialized(void *address, unsigned int n)
+{
+	mark_shadow(address, n, KMEMCHECK_SHADOW_INITIALIZED);
+}
+EXPORT_SYMBOL_GPL(kmemcheck_mark_initialized);
+
+void kmemcheck_mark_freed(void *address, unsigned int n)
+{
+	mark_shadow(address, n, KMEMCHECK_SHADOW_FREED);
+}
+
+void kmemcheck_mark_unallocated_pages(struct page *p, unsigned int n)
+{
+	unsigned int i;
+
+	for (i = 0; i < n; ++i)
+		kmemcheck_mark_unallocated(page_address(&p[i]), PAGE_SIZE);
+}
+
+void kmemcheck_mark_uninitialized_pages(struct page *p, unsigned int n)
+{
+	unsigned int i;
+
+	for (i = 0; i < n; ++i)
+		kmemcheck_mark_uninitialized(page_address(&p[i]), PAGE_SIZE);
+}
+
+void kmemcheck_mark_initialized_pages(struct page *p, unsigned int n)
+{
+	unsigned int i;
+
+	for (i = 0; i < n; ++i)
+		kmemcheck_mark_initialized(page_address(&p[i]), PAGE_SIZE);
+}
+
+enum kmemcheck_shadow kmemcheck_shadow_test(void *shadow, unsigned int size)
+{
+	uint8_t *x;
+	unsigned int i;
+
+	x = shadow;
+
+#ifdef CONFIG_KMEMCHECK_PARTIAL_OK
+	/*
+	 * Make sure _some_ bytes are initialized. Gcc frequently generates
+	 * code to access neighboring bytes.
+	 */
+	for (i = 0; i < size; ++i) {
+		if (x[i] == KMEMCHECK_SHADOW_INITIALIZED)
+			return x[i];
+	}
+#else
+	/* All bytes must be initialized. */
+	for (i = 0; i < size; ++i) {
+		if (x[i] != KMEMCHECK_SHADOW_INITIALIZED)
+			return x[i];
+	}
+#endif
+
+	return x[0];
+}
+
+void kmemcheck_shadow_set(void *shadow, unsigned int size)
+{
+	uint8_t *x;
+	unsigned int i;
+
+	x = shadow;
+	for (i = 0; i < size; ++i)
+		x[i] = KMEMCHECK_SHADOW_INITIALIZED;
+}
diff --git a/arch/x86/mm/kmemcheck/shadow.h b/arch/x86/mm/kmemcheck/shadow.h
new file mode 100644
index 000000000000..af46d9ab9d86
--- /dev/null
+++ b/arch/x86/mm/kmemcheck/shadow.h
@@ -0,0 +1,16 @@
+#ifndef ARCH__X86__MM__KMEMCHECK__SHADOW_H
+#define ARCH__X86__MM__KMEMCHECK__SHADOW_H
+
+enum kmemcheck_shadow {
+	KMEMCHECK_SHADOW_UNALLOCATED,
+	KMEMCHECK_SHADOW_UNINITIALIZED,
+	KMEMCHECK_SHADOW_INITIALIZED,
+	KMEMCHECK_SHADOW_FREED,
+};
+
+void *kmemcheck_shadow_lookup(unsigned long address);
+
+enum kmemcheck_shadow kmemcheck_shadow_test(void *shadow, unsigned int size);
+void kmemcheck_shadow_set(void *shadow, unsigned int size);
+
+#endif
diff --git a/arch/x86/mm/memtest.c b/arch/x86/mm/memtest.c
index 605c8be06217..18d244f70205 100644
--- a/arch/x86/mm/memtest.c
+++ b/arch/x86/mm/memtest.c
@@ -40,23 +40,22 @@ static void __init reserve_bad_mem(u64 pattern, u64 start_bad, u64 end_bad)
 
 static void __init memtest(u64 pattern, u64 start_phys, u64 size)
 {
-	u64 i, count;
-	u64 *start;
+	u64 *p, *start, *end;
 	u64 start_bad, last_bad;
 	u64 start_phys_aligned;
-	size_t incr;
+	const size_t incr = sizeof(pattern);
 
-	incr = sizeof(pattern);
 	start_phys_aligned = ALIGN(start_phys, incr);
-	count = (size - (start_phys_aligned - start_phys))/incr;
 	start = __va(start_phys_aligned);
+	end = start + (size - (start_phys_aligned - start_phys)) / incr;
 	start_bad = 0;
 	last_bad = 0;
 
-	for (i = 0; i < count; i++)
-		start[i] = pattern;
-	for (i = 0; i < count; i++, start++, start_phys_aligned += incr) {
-		if (*start == pattern)
+	for (p = start; p < end; p++)
+		*p = pattern;
+
+	for (p = start; p < end; p++, start_phys_aligned += incr) {
+		if (*p == pattern)
 			continue;
 		if (start_phys_aligned == last_bad + incr) {
 			last_bad += incr;
diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c
index 2d05a12029dc..459913beac71 100644
--- a/arch/x86/mm/numa_64.c
+++ b/arch/x86/mm/numa_64.c
@@ -179,18 +179,25 @@ static void * __init early_node_mem(int nodeid, unsigned long start,
 }
 
 /* Initialize bootmem allocator for a node */
-void __init setup_node_bootmem(int nodeid, unsigned long start,
-			       unsigned long end)
+void __init
+setup_node_bootmem(int nodeid, unsigned long start, unsigned long end)
 {
 	unsigned long start_pfn, last_pfn, bootmap_pages, bootmap_size;
+	const int pgdat_size = roundup(sizeof(pg_data_t), PAGE_SIZE);
 	unsigned long bootmap_start, nodedata_phys;
 	void *bootmap;
-	const int pgdat_size = roundup(sizeof(pg_data_t), PAGE_SIZE);
 	int nid;
 
 	if (!end)
 		return;
 
+	/*
+	 * Don't confuse VM with a node that doesn't have the
+	 * minimum amount of memory:
+	 */
+	if (end && (end - start) < NODE_MIN_SIZE)
+		return;
+
 	start = roundup(start, ZONE_ALIGN);
 
 	printk(KERN_INFO "Bootmem setup node %d %016lx-%016lx\n", nodeid,
@@ -272,9 +279,6 @@ void __init setup_node_bootmem(int nodeid, unsigned long start,
 		reserve_bootmem_node(NODE_DATA(nodeid), bootmap_start,
 				 bootmap_pages<<PAGE_SHIFT, BOOTMEM_DEFAULT);
 
-#ifdef CONFIG_ACPI_NUMA
-	srat_reserve_add_area(nodeid);
-#endif
 	node_set_online(nodeid);
 }
 
@@ -578,21 +582,6 @@ unsigned long __init numa_free_all_bootmem(void)
 	return pages;
 }
 
-void __init paging_init(void)
-{
-	unsigned long max_zone_pfns[MAX_NR_ZONES];
-
-	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
-	max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
-	max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
-	max_zone_pfns[ZONE_NORMAL] = max_pfn;
-
-	sparse_memory_present_with_active_regions(MAX_NUMNODES);
-	sparse_init();
-
-	free_area_init_nodes(max_zone_pfns);
-}
-
 static __init int numa_setup(char *opt)
 {
 	if (!opt)
@@ -606,8 +595,6 @@ static __init int numa_setup(char *opt)
 #ifdef CONFIG_ACPI_NUMA
 	if (!strncmp(opt, "noacpi", 6))
 		acpi_numa = -1;
-	if (!strncmp(opt, "hotadd=", 7))
-		hotadd_percent = simple_strtoul(opt+7, NULL, 10);
 #endif
 	return 0;
 }
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 797f9f107cb6..3cfe9ced8a4c 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -153,7 +153,7 @@ static void __cpa_flush_all(void *arg)
 	 */
 	__flush_tlb_all();
 
-	if (cache && boot_cpu_data.x86_model >= 4)
+	if (cache && boot_cpu_data.x86 >= 4)
 		wbinvd();
 }
 
@@ -208,20 +208,15 @@ static void cpa_flush_array(unsigned long *start, int numpages, int cache,
 			    int in_flags, struct page **pages)
 {
 	unsigned int i, level;
+	unsigned long do_wbinvd = cache && numpages >= 1024; /* 4M threshold */
 
 	BUG_ON(irqs_disabled());
 
-	on_each_cpu(__cpa_flush_range, NULL, 1);
+	on_each_cpu(__cpa_flush_all, (void *) do_wbinvd, 1);
 
-	if (!cache)
+	if (!cache || do_wbinvd)
 		return;
 
-	/* 4M threshold */
-	if (numpages >= 1024) {
-		if (boot_cpu_data.x86_model >= 4)
-			wbinvd();
-		return;
-	}
 	/*
 	 * We only need to flush on one CPU,
 	 * clflush is a MESI-coherent instruction that
@@ -475,7 +470,7 @@ static int split_large_page(pte_t *kpte, unsigned long address)
 
 	if (!debug_pagealloc)
 		spin_unlock(&cpa_lock);
-	base = alloc_pages(GFP_KERNEL, 0);
+	base = alloc_pages(GFP_KERNEL | __GFP_NOTRACK, 0);
 	if (!debug_pagealloc)
 		spin_lock(&cpa_lock);
 	if (!base)
@@ -844,13 +839,6 @@ static int change_page_attr_set_clr(unsigned long *addr, int numpages,
 
 	vm_unmap_aliases();
 
-	/*
-	 * If we're called with lazy mmu updates enabled, the
-	 * in-memory pte state may be stale.  Flush pending updates to
-	 * bring them up to date.
-	 */
-	arch_flush_lazy_mmu_mode();
-
 	cpa.vaddr = addr;
 	cpa.pages = pages;
 	cpa.numpages = numpages;
@@ -895,13 +883,6 @@ static int change_page_attr_set_clr(unsigned long *addr, int numpages,
 	} else
 		cpa_flush_all(cache);
 
-	/*
-	 * If we've been called with lazy mmu updates enabled, then
-	 * make sure that everything gets flushed out before we
-	 * return.
-	 */
-	arch_flush_lazy_mmu_mode();
-
 out:
 	return ret;
 }
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index 7aa03a5389f5..8e43bdd45456 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -4,9 +4,11 @@
 #include <asm/tlb.h>
 #include <asm/fixmap.h>
 
+#define PGALLOC_GFP GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO
+
 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
-	return (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+	return (pte_t *)__get_free_page(PGALLOC_GFP);
 }
 
 pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
@@ -14,9 +16,9 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
 	struct page *pte;
 
 #ifdef CONFIG_HIGHPTE
-	pte = alloc_pages(GFP_KERNEL|__GFP_HIGHMEM|__GFP_REPEAT|__GFP_ZERO, 0);
+	pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0);
 #else
-	pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
+	pte = alloc_pages(PGALLOC_GFP, 0);
 #endif
 	if (pte)
 		pgtable_page_ctor(pte);
@@ -161,7 +163,7 @@ static int preallocate_pmds(pmd_t *pmds[])
 	bool failed = false;
 
 	for(i = 0; i < PREALLOCATED_PMDS; i++) {
-		pmd_t *pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
+		pmd_t *pmd = (pmd_t *)__get_free_page(PGALLOC_GFP);
 		if (pmd == NULL)
 			failed = true;
 		pmds[i] = pmd;
@@ -228,7 +230,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
 	pmd_t *pmds[PREALLOCATED_PMDS];
 	unsigned long flags;
 
-	pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
+	pgd = (pgd_t *)__get_free_page(PGALLOC_GFP);
 
 	if (pgd == NULL)
 		goto out;
diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c
index 01765955baaf..2dfcbf9df2ae 100644
--- a/arch/x86/mm/srat_64.c
+++ b/arch/x86/mm/srat_64.c
@@ -31,17 +31,11 @@ static nodemask_t nodes_parsed __initdata;
 static nodemask_t cpu_nodes_parsed __initdata;
 static struct bootnode nodes[MAX_NUMNODES] __initdata;
 static struct bootnode nodes_add[MAX_NUMNODES];
-static int found_add_area __initdata;
-int hotadd_percent __initdata = 0;
 
 static int num_node_memblks __initdata;
 static struct bootnode node_memblk_range[NR_NODE_MEMBLKS] __initdata;
 static int memblk_nodeid[NR_NODE_MEMBLKS] __initdata;
 
-/* Too small nodes confuse the VM badly. Usually they result
-   from BIOS bugs. */
-#define NODE_MIN_SIZE (4*1024*1024)
-
 static __init int setup_node(int pxm)
 {
 	return acpi_map_pxm_to_node(pxm);
@@ -66,9 +60,6 @@ static __init void cutoff_node(int i, unsigned long start, unsigned long end)
 {
 	struct bootnode *nd = &nodes[i];
 
-	if (found_add_area)
-		return;
-
 	if (nd->start < start) {
 		nd->start = start;
 		if (nd->end < nd->start)
@@ -86,7 +77,6 @@ static __init void bad_srat(void)
 	int i;
 	printk(KERN_ERR "SRAT: SRAT not used.\n");
 	acpi_numa = -1;
-	found_add_area = 0;
 	for (i = 0; i < MAX_LOCAL_APIC; i++)
 		apicid_to_node[i] = NUMA_NO_NODE;
 	for (i = 0; i < MAX_NUMNODES; i++)
@@ -182,24 +172,21 @@ acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity *pa)
 	       pxm, apic_id, node);
 }
 
-static int update_end_of_memory(unsigned long end) {return -1;}
-static int hotadd_enough_memory(struct bootnode *nd) {return 1;}
 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
 static inline int save_add_info(void) {return 1;}
 #else
 static inline int save_add_info(void) {return 0;}
 #endif
 /*
- * Update nodes_add and decide if to include add are in the zone.
- * Both SPARSE and RESERVE need nodes_add information.
- * This code supports one contiguous hot add area per node.
+ * Update nodes_add[]
+ * This code supports one contiguous hot add area per node
  */
-static int __init
-reserve_hotadd(int node, unsigned long start, unsigned long end)
+static void __init
+update_nodes_add(int node, unsigned long start, unsigned long end)
 {
 	unsigned long s_pfn = start >> PAGE_SHIFT;
 	unsigned long e_pfn = end >> PAGE_SHIFT;
-	int ret = 0, changed = 0;
+	int changed = 0;
 	struct bootnode *nd = &nodes_add[node];
 
 	/* I had some trouble with strange memory hotadd regions breaking
@@ -210,7 +197,7 @@ reserve_hotadd(int node, unsigned long start, unsigned long end)
 	   mistakes */
 	if ((signed long)(end - start) < NODE_MIN_SIZE) {
 		printk(KERN_ERR "SRAT: Hotplug area too small\n");
-		return -1;
+		return;
 	}
 
 	/* This check might be a bit too strict, but I'm keeping it for now. */
@@ -218,12 +205,7 @@ reserve_hotadd(int node, unsigned long start, unsigned long end)
 		printk(KERN_ERR
 			"SRAT: Hotplug area %lu -> %lu has existing memory\n",
 			s_pfn, e_pfn);
-		return -1;
-	}
-
-	if (!hotadd_enough_memory(&nodes_add[node]))  {
-		printk(KERN_ERR "SRAT: Hotplug area too large\n");
-		return -1;
+		return;
 	}
 
 	/* Looks good */
@@ -245,11 +227,9 @@ reserve_hotadd(int node, unsigned long start, unsigned long end)
 			printk(KERN_ERR "SRAT: Hotplug zone not continuous. Partly ignored\n");
 	}
 
-	ret = update_end_of_memory(nd->end);
-
 	if (changed)
-	 	printk(KERN_INFO "SRAT: hot plug zone found %Lx - %Lx\n", nd->start, nd->end);
-	return ret;
+		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 */
@@ -310,13 +290,10 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
 	       start, end);
 	e820_register_active_regions(node, start >> PAGE_SHIFT,
 				     end >> PAGE_SHIFT);
-	push_node_boundaries(node, nd->start >> PAGE_SHIFT,
-						nd->end >> PAGE_SHIFT);
 
-	if ((ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) &&
-	    (reserve_hotadd(node, start, end) < 0)) {
-		/* Ignore hotadd region. Undo damage */
-		printk(KERN_NOTICE "SRAT: Hotplug region ignored\n");
+	if (ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) {
+		update_nodes_add(node, start, end);
+		/* restore nodes[node] */
 		*nd = oldnode;
 		if ((nd->start | nd->end) == 0)
 			node_clear(node, nodes_parsed);
@@ -345,9 +322,9 @@ static int __init nodes_cover_memory(const struct bootnode *nodes)
 			pxmram = 0;
 	}
 
-	e820ram = max_pfn - absent_pages_in_range(0, max_pfn);
-	/* We seem to lose 3 pages somewhere. Allow a bit of slack. */
-	if ((long)(e820ram - pxmram) >= 1*1024*1024) {
+	e820ram = max_pfn - (e820_hole_size(0, max_pfn<<PAGE_SHIFT)>>PAGE_SHIFT);
+	/* We seem to lose 3 pages somewhere. Allow 1M of slack. */
+	if ((long)(e820ram - pxmram) >= (1<<(20 - PAGE_SHIFT))) {
 		printk(KERN_ERR
 	"SRAT: PXMs only cover %luMB of your %luMB e820 RAM. Not used.\n",
 			(pxmram << PAGE_SHIFT) >> 20,
@@ -357,17 +334,6 @@ static int __init nodes_cover_memory(const struct bootnode *nodes)
 	return 1;
 }
 
-static void __init unparse_node(int node)
-{
-	int i;
-	node_clear(node, nodes_parsed);
-	node_clear(node, cpu_nodes_parsed);
-	for (i = 0; i < MAX_LOCAL_APIC; i++) {
-		if (apicid_to_node[i] == node)
-			apicid_to_node[i] = NUMA_NO_NODE;
-	}
-}
-
 void __init acpi_numa_arch_fixup(void) {}
 
 /* Use the information discovered above to actually set up the nodes. */
@@ -379,18 +345,8 @@ int __init acpi_scan_nodes(unsigned long start, unsigned long end)
 		return -1;
 
 	/* First clean up the node list */
-	for (i = 0; i < MAX_NUMNODES; i++) {
+	for (i = 0; i < MAX_NUMNODES; i++)
 		cutoff_node(i, start, end);
-		/*
-		 * don't confuse VM with a node that doesn't have the
-		 * minimum memory.
-		 */
-		if (nodes[i].end &&
-			(nodes[i].end - nodes[i].start) < NODE_MIN_SIZE) {
-			unparse_node(i);
-			node_set_offline(i);
-		}
-	}
 
 	if (!nodes_cover_memory(nodes)) {
 		bad_srat();
@@ -423,7 +379,7 @@ int __init acpi_scan_nodes(unsigned long start, unsigned long end)
 
 		if (node == NUMA_NO_NODE)
 			continue;
-		if (!node_isset(node, node_possible_map))
+		if (!node_online(node))
 			numa_clear_node(i);
 	}
 	numa_init_array();
@@ -510,26 +466,6 @@ static int null_slit_node_compare(int a, int b)
 }
 #endif /* CONFIG_NUMA_EMU */
 
-void __init srat_reserve_add_area(int nodeid)
-{
-	if (found_add_area && nodes_add[nodeid].end) {
-		u64 total_mb;
-
-		printk(KERN_INFO "SRAT: Reserving hot-add memory space "
-				"for node %d at %Lx-%Lx\n",
-			nodeid, nodes_add[nodeid].start, nodes_add[nodeid].end);
-		total_mb = (nodes_add[nodeid].end - nodes_add[nodeid].start)
-					>> PAGE_SHIFT;
-		total_mb *= sizeof(struct page);
-		total_mb >>= 20;
-		printk(KERN_INFO "SRAT: This will cost you %Lu MB of "
-				"pre-allocated memory.\n", (unsigned long long)total_mb);
-		reserve_bootmem_node(NODE_DATA(nodeid), nodes_add[nodeid].start,
-			       nodes_add[nodeid].end - nodes_add[nodeid].start,
-			       BOOTMEM_DEFAULT);
-	}
-}
-
 int __node_distance(int a, int b)
 {
 	int index;