Merge 'akpm' patch series

* Merge akpm patch series: (122 commits)
  drivers/connector/cn_proc.c: remove unused local
  Documentation/SubmitChecklist: add RCU debug config options
  reiserfs: use hweight_long()
  reiserfs: use proper little-endian bitops
  pnpacpi: register disabled resources
  drivers/rtc/rtc-tegra.c: properly initialize spinlock
  drivers/rtc/rtc-twl.c: check return value of twl_rtc_write_u8() in twl_rtc_set_time()
  drivers/rtc: add support for Qualcomm PMIC8xxx RTC
  drivers/rtc/rtc-s3c.c: support clock gating
  drivers/rtc/rtc-mpc5121.c: add support for RTC on MPC5200
  init: skip calibration delay if previously done
  misc/eeprom: add eeprom access driver for digsy_mtc board
  misc/eeprom: add driver for microwire 93xx46 EEPROMs
  checkpatch.pl: update $logFunctions
  checkpatch: make utf-8 test --strict
  checkpatch.pl: add ability to ignore various messages
  checkpatch: add a "prefer __aligned" check
  checkpatch: validate signature styles and To: and Cc: lines
  checkpatch: add __rcu as a sparse modifier
  checkpatch: suggest using min_t or max_t
  ...

Did this as a merge because of (trivial) conflicts in
 - Documentation/feature-removal-schedule.txt
 - arch/xtensa/include/asm/uaccess.h
that were just easier to fix up in the merge than in the patch series.

54 files changed, 965 insertions, 133 deletions

diff --git a/arch/alpha/kernel/process.c b/arch/alpha/kernel/process.c
index 838eac1..89bbe5b 100644
--- a/arch/alpha/kernel/process.c
+++ b/arch/alpha/kernel/process.c
@@ -200,7 +200,6 @@ show_regs(struct pt_regs *regs)
 void
 start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp)
 {
-	set_fs(USER_DS);
 	regs->pc = pc;
 	regs->ps = 8;
 	wrusp(sp);
diff --git a/arch/arm/mach-ux500/board-u5500.c b/arch/arm/mach-ux500/board-u5500.c
index 44fd3b5..e58f0f5 100644
--- a/arch/arm/mach-ux500/board-u5500.c
+++ b/arch/arm/mach-ux500/board-u5500.c
@@ -10,16 +10,97 @@
 #include <linux/amba/bus.h>
 #include <linux/gpio.h>
 #include <linux/irq.h>
+#include <linux/i2c.h>
 
 #include <asm/mach/arch.h>
 #include <asm/mach-types.h>
 
+#include <plat/pincfg.h>
+#include <plat/i2c.h>
+
 #include <mach/hardware.h>
 #include <mach/devices.h>
 #include <mach/setup.h>
 
+#include "pins-db5500.h"
 #include "devices-db5500.h"
+#include <linux/led-lm3530.h>
+
+/*
+ * GPIO
+ */
+
+static pin_cfg_t u5500_pins[] = {
+	/* I2C */
+	GPIO218_I2C2_SCL        | PIN_INPUT_PULLUP,
+	GPIO219_I2C2_SDA        | PIN_INPUT_PULLUP,
+
+	/* DISPLAY_ENABLE */
+	GPIO226_GPIO        | PIN_OUTPUT_LOW,
+
+	/* Backlight Enbale */
+	GPIO224_GPIO        | PIN_OUTPUT_HIGH,
+};
+/*
+ * I2C
+ */
+
+#define U5500_I2C_CONTROLLER(id, _slsu, _tft, _rft, clk, _sm) \
+static struct nmk_i2c_controller u5500_i2c##id##_data = { \
+	/*				\
+	 * slave data setup time, which is	\
+	 * 250 ns,100ns,10ns which is 14,6,2	\
+	 * respectively for a 48 Mhz	\
+	 * i2c clock			\
+	 */				\
+	.slsu		= _slsu,	\
+	/* Tx FIFO threshold */		\
+	.tft		= _tft,		\
+	/* Rx FIFO threshold */		\
+	.rft		= _rft,		\
+	/* std. mode operation */	\
+	.clk_freq	= clk,		\
+	.sm		= _sm,		\
+}
+/*
+ * The board uses TODO <3> i2c controllers, initialize all of
+ * them with slave data setup time of 250 ns,
+ * Tx & Rx FIFO threshold values as 1 and standard
+ * mode of operation
+ */
+
+U5500_I2C_CONTROLLER(2,	0xe, 1, 1, 400000, I2C_FREQ_MODE_FAST);
+
+static struct lm3530_platform_data u5500_als_platform_data = {
+	.mode = LM3530_BL_MODE_MANUAL,
+	.als_input_mode = LM3530_INPUT_ALS1,
+	.max_current = LM3530_FS_CURR_26mA,
+	.pwm_pol_hi = true,
+	.als_avrg_time = LM3530_ALS_AVRG_TIME_512ms,
+	.brt_ramp_law = 1,      /* Linear */
+	.brt_ramp_fall = LM3530_RAMP_TIME_8s,
+	.brt_ramp_rise = LM3530_RAMP_TIME_8s,
+	.als1_resistor_sel = LM3530_ALS_IMPD_13_53kOhm,
+	.als2_resistor_sel = LM3530_ALS_IMPD_Z,
+	.als_vmin = 730,	/* mV */
+	.als_vmax = 1020,	/* mV */
+	.brt_val = 0x7F,	/* Max brightness */
+};
 
+
+static struct i2c_board_info __initdata u5500_i2c2_devices[] = {
+	{
+		/* Backlight */
+		I2C_BOARD_INFO("lm3530-led", 0x36),
+		.platform_data = &u5500_als_platform_data,
+	},
+};
+
+static void __init u5500_i2c_init(void)
+{
+	db5500_add_i2c2(&u5500_i2c2_data);
+	i2c_register_board_info(2, ARRAY_AND_SIZE(u5500_i2c2_devices));
+}
 static void __init u5500_uart_init(void)
 {
 	db5500_add_uart0(NULL);
@@ -30,7 +111,8 @@ static void __init u5500_uart_init(void)
 static void __init u5500_init_machine(void)
 {
 	u5500_init_devices();
-
+	nmk_config_pins(u5500_pins, ARRAY_SIZE(u5500_pins));
+	u5500_i2c_init();
 	u5500_sdi_init();
 	u5500_uart_init();
 }
diff --git a/arch/cris/arch-v32/mach-a3/pinmux.c b/arch/cris/arch-v32/mach-a3/pinmux.c
index 18648ef..591f775 100644
--- a/arch/cris/arch-v32/mach-a3/pinmux.c
+++ b/arch/cris/arch-v32/mach-a3/pinmux.c
@@ -85,6 +85,8 @@ crisv32_pinmux_alloc_fixed(enum fixed_function function)
 	int ret = -EINVAL;
 	char saved[sizeof pins];
 	unsigned long flags;
+	reg_pinmux_rw_hwprot hwprot;
+	reg_clkgen_rw_clk_ctrl clk_ctrl;
 
 	spin_lock_irqsave(&pinmux_lock, flags);
 
@@ -93,9 +95,8 @@ crisv32_pinmux_alloc_fixed(enum fixed_function function)
 
 	crisv32_pinmux_init(); /* must be done before we read rw_hwprot */
 
-	reg_pinmux_rw_hwprot hwprot = REG_RD(pinmux, regi_pinmux, rw_hwprot);
-	reg_clkgen_rw_clk_ctrl clk_ctrl = REG_RD(clkgen, regi_clkgen,
-		rw_clk_ctrl);
+	hwprot = REG_RD(pinmux, regi_pinmux, rw_hwprot);
+	clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);
 
 	switch (function) {
 	case pinmux_eth:
@@ -262,6 +263,7 @@ crisv32_pinmux_dealloc_fixed(enum fixed_function function)
 	int ret = -EINVAL;
 	char saved[sizeof pins];
 	unsigned long flags;
+	reg_pinmux_rw_hwprot hwprot;
 
 	spin_lock_irqsave(&pinmux_lock, flags);
 
@@ -270,7 +272,7 @@ crisv32_pinmux_dealloc_fixed(enum fixed_function function)
 
 	crisv32_pinmux_init(); /* must be done before we read rw_hwprot */
 
-	reg_pinmux_rw_hwprot hwprot = REG_RD(pinmux, regi_pinmux, rw_hwprot);
+	hwprot = REG_RD(pinmux, regi_pinmux, rw_hwprot);
 
 	switch (function) {
 	case pinmux_eth:
diff --git a/arch/cris/include/arch-v10/arch/processor.h b/arch/cris/include/arch-v10/arch/processor.h
index cc692c7..93feb2a 100644
--- a/arch/cris/include/arch-v10/arch/processor.h
+++ b/arch/cris/include/arch-v10/arch/processor.h
@@ -53,7 +53,6 @@ struct thread_struct {
  */
 
 #define start_thread(regs, ip, usp) do { \
-	set_fs(USER_DS);      \
 	regs->irp = ip;       \
 	regs->dccr |= 1 << U_DCCR_BITNR; \
 	wrusp(usp);           \
diff --git a/arch/cris/include/arch-v32/arch/processor.h b/arch/cris/include/arch-v32/arch/processor.h
index f80b477..9603c90 100644
--- a/arch/cris/include/arch-v32/arch/processor.h
+++ b/arch/cris/include/arch-v32/arch/processor.h
@@ -47,7 +47,6 @@ struct thread_struct {
  */
 #define start_thread(regs, ip, usp) \
 do { \
-	set_fs(USER_DS); \
 	regs->erp = ip; \
 	regs->ccs |= 1 << (U_CCS_BITNR + CCS_SHIFT); \
 	wrusp(usp); \
diff --git a/arch/h8300/include/asm/processor.h b/arch/h8300/include/asm/processor.h
index 69e8a34..e834b60 100644
--- a/arch/h8300/include/asm/processor.h
+++ b/arch/h8300/include/asm/processor.h
@@ -81,7 +81,6 @@ struct thread_struct {
 #if defined(__H8300H__)
 #define start_thread(_regs, _pc, _usp)			        \
 do {							        \
-	set_fs(USER_DS);           /* reads from user space */  \
   	(_regs)->pc = (_pc);				        \
 	(_regs)->ccr = 0x00;	   /* clear all flags */        \
 	(_regs)->er5 = current->mm->start_data;	/* GOT base */  \
@@ -91,7 +90,6 @@ do {							        \
 #if defined(__H8300S__)
 #define start_thread(_regs, _pc, _usp)			        \
 do {							        \
-	set_fs(USER_DS);           /* reads from user space */  \
 	(_regs)->pc = (_pc);				        \
 	(_regs)->ccr = 0x00;	   /* clear kernel flag */      \
 	(_regs)->exr = 0x78;       /* enable all interrupts */  \
diff --git a/arch/m32r/include/asm/processor.h b/arch/m32r/include/asm/processor.h
index 8397c24..e1f46d7 100644
--- a/arch/m32r/include/asm/processor.h
+++ b/arch/m32r/include/asm/processor.h
@@ -106,7 +106,6 @@ struct thread_struct {
 
 #define start_thread(regs, new_pc, new_spu) 				\
 	do {								\
-		set_fs(USER_DS); 					\
 		regs->psw = (regs->psw | USERPS_BPSW) & 0x0000FFFFUL;	\
 		regs->bpc = new_pc;					\
 		regs->spu = new_spu;					\
diff --git a/arch/m68k/include/asm/processor.h b/arch/m68k/include/asm/processor.h
index f111b02..d8ef53a 100644
--- a/arch/m68k/include/asm/processor.h
+++ b/arch/m68k/include/asm/processor.h
@@ -105,9 +105,6 @@ struct thread_struct {
 static inline void start_thread(struct pt_regs * regs, unsigned long pc,
 				unsigned long usp)
 {
-	/* reads from user space */
-	set_fs(USER_DS);
-
 	regs->pc = pc;
 	regs->sr &= ~0x2000;
 	wrusp(usp);
@@ -129,7 +126,6 @@ extern int handle_kernel_fault(struct pt_regs *regs);
 
 #define start_thread(_regs, _pc, _usp)                  \
 do {                                                    \
-	set_fs(USER_DS); /* reads from user space */    \
 	(_regs)->pc = (_pc);                            \
 	((struct switch_stack *)(_regs))[-1].a6 = 0;    \
 	reformat(_regs);                                \
diff --git a/arch/m68k/kernel/process_mm.c b/arch/m68k/kernel/process_mm.c
index c2a1fc2..1bc223a 100644
--- a/arch/m68k/kernel/process_mm.c
+++ b/arch/m68k/kernel/process_mm.c
@@ -185,7 +185,7 @@ EXPORT_SYMBOL(kernel_thread);
 void flush_thread(void)
 {
 	unsigned long zero = 0;
-	set_fs(USER_DS);
+
 	current->thread.fs = __USER_DS;
 	if (!FPU_IS_EMU)
 		asm volatile (".chip 68k/68881\n\t"
diff --git a/arch/m68k/kernel/process_no.c b/arch/m68k/kernel/process_no.c
index 9b86ad1..69c1803 100644
--- a/arch/m68k/kernel/process_no.c
+++ b/arch/m68k/kernel/process_no.c
@@ -158,7 +158,7 @@ void flush_thread(void)
 #ifdef CONFIG_FPU
 	unsigned long zero = 0;
 #endif
-	set_fs(USER_DS);
+
 	current->thread.fs = __USER_DS;
 #ifdef CONFIG_FPU
 	if (!FPU_IS_EMU)
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index 271ff63..0e0ea94 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -24,6 +24,7 @@
 #include <linux/cpumask.h>
 #include <linux/memblock.h>
 #include <linux/slab.h>
+#include <linux/reboot.h>
 
 #include <asm/prom.h>
 #include <asm/rtas.h>
diff --git a/arch/powerpc/kernel/rtas_flash.c b/arch/powerpc/kernel/rtas_flash.c
index bf5f5ce..e037c74 100644
--- a/arch/powerpc/kernel/rtas_flash.c
+++ b/arch/powerpc/kernel/rtas_flash.c
@@ -17,6 +17,7 @@
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/proc_fs.h>
+#include <linux/reboot.h>
 #include <asm/delay.h>
 #include <asm/uaccess.h>
 #include <asm/rtas.h>
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 253986b..1074ddd 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -41,6 +41,7 @@ config SPARC64
 	select HAVE_FUNCTION_TRACE_MCOUNT_TEST
 	select HAVE_KRETPROBES
 	select HAVE_KPROBES
+	select HAVE_RCU_TABLE_FREE if SMP
 	select HAVE_MEMBLOCK
 	select HAVE_SYSCALL_WRAPPERS
 	select HAVE_DYNAMIC_FTRACE
@@ -81,10 +82,6 @@ config IOMMU_HELPER
 	bool
 	default y if SPARC64
 
-config QUICKLIST
-	bool
-	default y if SPARC64
-
 config STACKTRACE_SUPPORT
 	bool
 	default y if SPARC64
diff --git a/arch/sparc/include/asm/pgalloc_64.h b/arch/sparc/include/asm/pgalloc_64.h
index 4e5e087..40b2d7a 100644
--- a/arch/sparc/include/asm/pgalloc_64.h
+++ b/arch/sparc/include/asm/pgalloc_64.h
@@ -5,7 +5,6 @@
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
-#include <linux/quicklist.h>
 
 #include <asm/spitfire.h>
 #include <asm/cpudata.h>
@@ -14,71 +13,114 @@
 
 /* Page table allocation/freeing. */
 
+extern struct kmem_cache *pgtable_cache;
+
 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 {
-	return quicklist_alloc(0, GFP_KERNEL, NULL);
+	return kmem_cache_alloc(pgtable_cache, GFP_KERNEL);
 }
 
 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 {
-	quicklist_free(0, NULL, pgd);
+	kmem_cache_free(pgtable_cache, pgd);
 }
 
 #define pud_populate(MM, PUD, PMD)	pud_set(PUD, PMD)
 
 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-	return quicklist_alloc(0, GFP_KERNEL, NULL);
+	return kmem_cache_alloc(pgtable_cache,
+				GFP_KERNEL|__GFP_REPEAT);
 }
 
 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
 {
-	quicklist_free(0, NULL, pmd);
+	kmem_cache_free(pgtable_cache, pmd);
 }
 
 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 					  unsigned long address)
 {
-	return quicklist_alloc(0, GFP_KERNEL, NULL);
+	return (pte_t *)__get_free_page(GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO);
 }
 
 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
 					unsigned long address)
 {
 	struct page *page;
-	void *pg;
+	pte_t *pte;
 
-	pg = quicklist_alloc(0, GFP_KERNEL, NULL);
-	if (!pg)
+	pte = pte_alloc_one_kernel(mm, address);
+	if (!pte)
 		return NULL;
-	page = virt_to_page(pg);
+	page = virt_to_page(pte);
 	pgtable_page_ctor(page);
 	return page;
 }
 
 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
 {
-	quicklist_free(0, NULL, pte);
+	free_page((unsigned long)pte);
 }
 
 static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
 {
 	pgtable_page_dtor(ptepage);
-	quicklist_free_page(0, NULL, ptepage);
+	__free_page(ptepage);
 }
 
-
 #define pmd_populate_kernel(MM, PMD, PTE)	pmd_set(PMD, PTE)
 #define pmd_populate(MM,PMD,PTE_PAGE)		\
 	pmd_populate_kernel(MM,PMD,page_address(PTE_PAGE))
 #define pmd_pgtable(pmd) pmd_page(pmd)
 
-static inline void check_pgt_cache(void)
+#define check_pgt_cache()	do { } while (0)
+
+static inline void pgtable_free(void *table, bool is_page)
+{
+	if (is_page)
+		free_page((unsigned long)table);
+	else
+		kmem_cache_free(pgtable_cache, table);
+}
+
+#ifdef CONFIG_SMP
+
+struct mmu_gather;
+extern void tlb_remove_table(struct mmu_gather *, void *);
+
+static inline void pgtable_free_tlb(struct mmu_gather *tlb, void *table, bool is_page)
+{
+	unsigned long pgf = (unsigned long)table;
+	if (is_page)
+		pgf |= 0x1UL;
+	tlb_remove_table(tlb, (void *)pgf);
+}
+
+static inline void __tlb_remove_table(void *_table)
+{
+	void *table = (void *)((unsigned long)_table & ~0x1UL);
+	bool is_page = false;
+
+	if ((unsigned long)_table & 0x1UL)
+		is_page = true;
+	pgtable_free(table, is_page);
+}
+#else /* CONFIG_SMP */
+static inline void pgtable_free_tlb(struct mmu_gather *tlb, void *table, bool is_page)
 {
-	quicklist_trim(0, NULL, 25, 16);
+	pgtable_free(table, is_page);
+}
+#endif /* !CONFIG_SMP */
+
+static inline void __pte_free_tlb(struct mmu_gather *tlb, struct page *ptepage,
+				  unsigned long address)
+{
+	pgtable_page_dtor(ptepage);
+	pgtable_free_tlb(tlb, page_address(ptepage), true);
 }
 
-#define __pte_free_tlb(tlb, pte, addr)	pte_free((tlb)->mm, pte)
-#define __pmd_free_tlb(tlb, pmd, addr)	pmd_free((tlb)->mm, pmd)
+#define __pmd_free_tlb(tlb, pmd, addr)		      \
+	pgtable_free_tlb(tlb, pmd, false)
 
 #endif /* _SPARC64_PGALLOC_H */
diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h
index 1e03c5a..adf8932 100644
--- a/arch/sparc/include/asm/pgtable_64.h
+++ b/arch/sparc/include/asm/pgtable_64.h
@@ -95,6 +95,10 @@
 /* PTE bits which are the same in SUN4U and SUN4V format.  */
 #define _PAGE_VALID	  _AC(0x8000000000000000,UL) /* Valid TTE            */
 #define _PAGE_R	  	  _AC(0x8000000000000000,UL) /* Keep ref bit uptodate*/
+#define _PAGE_SPECIAL     _AC(0x0200000000000000,UL) /* Special page         */
+
+/* Advertise support for _PAGE_SPECIAL */
+#define __HAVE_ARCH_PTE_SPECIAL
 
 /* SUN4U pte bits... */
 #define _PAGE_SZ4MB_4U	  _AC(0x6000000000000000,UL) /* 4MB Page             */
@@ -104,6 +108,7 @@
 #define _PAGE_NFO_4U	  _AC(0x1000000000000000,UL) /* No Fault Only        */
 #define _PAGE_IE_4U	  _AC(0x0800000000000000,UL) /* Invert Endianness    */
 #define _PAGE_SOFT2_4U	  _AC(0x07FC000000000000,UL) /* Software bits, set 2 */
+#define _PAGE_SPECIAL_4U  _AC(0x0200000000000000,UL) /* Special page         */
 #define _PAGE_RES1_4U	  _AC(0x0002000000000000,UL) /* Reserved             */
 #define _PAGE_SZ32MB_4U	  _AC(0x0001000000000000,UL) /* (Panther) 32MB page  */
 #define _PAGE_SZ256MB_4U  _AC(0x2001000000000000,UL) /* (Panther) 256MB page */
@@ -133,6 +138,7 @@
 #define _PAGE_ACCESSED_4V _AC(0x1000000000000000,UL) /* Accessed (ref'd)     */
 #define _PAGE_READ_4V	  _AC(0x0800000000000000,UL) /* Readable SW Bit      */
 #define _PAGE_WRITE_4V	  _AC(0x0400000000000000,UL) /* Writable SW Bit      */
+#define _PAGE_SPECIAL_4V  _AC(0x0200000000000000,UL) /* Special page         */
 #define _PAGE_PADDR_4V	  _AC(0x00FFFFFFFFFFE000,UL) /* paddr[55:13]         */
 #define _PAGE_IE_4V	  _AC(0x0000000000001000,UL) /* Invert Endianness    */
 #define _PAGE_E_4V	  _AC(0x0000000000000800,UL) /* side-Effect          */
@@ -302,10 +308,10 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t prot)
 	: "=r" (mask), "=r" (tmp)
 	: "i" (_PAGE_PADDR_4U | _PAGE_MODIFIED_4U | _PAGE_ACCESSED_4U |
 	       _PAGE_CP_4U | _PAGE_CV_4U | _PAGE_E_4U | _PAGE_PRESENT_4U |
-	       _PAGE_SZBITS_4U),
+	       _PAGE_SZBITS_4U | _PAGE_SPECIAL),
 	  "i" (_PAGE_PADDR_4V | _PAGE_MODIFIED_4V | _PAGE_ACCESSED_4V |
 	       _PAGE_CP_4V | _PAGE_CV_4V | _PAGE_E_4V | _PAGE_PRESENT_4V |
-	       _PAGE_SZBITS_4V));
+	       _PAGE_SZBITS_4V | _PAGE_SPECIAL));
 
 	return __pte((pte_val(pte) & mask) | (pgprot_val(prot) & ~mask));
 }
@@ -502,6 +508,7 @@ static inline pte_t pte_mkyoung(pte_t pte)
 
 static inline pte_t pte_mkspecial(pte_t pte)
 {
+	pte_val(pte) |= _PAGE_SPECIAL;
 	return pte;
 }
 
@@ -607,9 +614,9 @@ static inline unsigned long pte_present(pte_t pte)
 	return val;
 }
 
-static inline int pte_special(pte_t pte)
+static inline unsigned long pte_special(pte_t pte)
 {
-	return 0;
+	return pte_val(pte) & _PAGE_SPECIAL;
 }
 
 #define pmd_set(pmdp, ptep)	\
diff --git a/arch/sparc/mm/Makefile b/arch/sparc/mm/Makefile
index 79836a7..e3cda21 100644
--- a/arch/sparc/mm/Makefile
+++ b/arch/sparc/mm/Makefile
@@ -4,7 +4,7 @@
 asflags-y := -ansi
 ccflags-y := -Werror
 
-obj-$(CONFIG_SPARC64)   += ultra.o tlb.o tsb.o
+obj-$(CONFIG_SPARC64)   += ultra.o tlb.o tsb.o gup.o
 obj-y                   += fault_$(BITS).o
 obj-y                   += init_$(BITS).o
 obj-$(CONFIG_SPARC32)   += loadmmu.o
diff --git a/arch/sparc/mm/gup.c b/arch/sparc/mm/gup.c
new file mode 100644
index 0000000..a986b5d
--- /dev/null
+++ b/arch/sparc/mm/gup.c
@@ -0,0 +1,181 @@
+/*
+ * Lockless get_user_pages_fast for sparc, cribbed from powerpc
+ *
+ * Copyright (C) 2008 Nick Piggin
+ * Copyright (C) 2008 Novell Inc.
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/vmstat.h>
+#include <linux/pagemap.h>
+#include <linux/rwsem.h>
+#include <asm/pgtable.h>
+
+/*
+ * The performance critical leaf functions are made noinline otherwise gcc
+ * inlines everything into a single function which results in too much
+ * register pressure.
+ */
+static noinline int gup_pte_range(pmd_t pmd, unsigned long addr,
+		unsigned long end, int write, struct page **pages, int *nr)
+{
+	unsigned long mask, result;
+	pte_t *ptep;
+
+	if (tlb_type == hypervisor) {
+		result = _PAGE_PRESENT_4V|_PAGE_P_4V;
+		if (write)
+			result |= _PAGE_WRITE_4V;
+	} else {
+		result = _PAGE_PRESENT_4U|_PAGE_P_4U;
+		if (write)
+			result |= _PAGE_WRITE_4U;
+	}
+	mask = result | _PAGE_SPECIAL;
+
+	ptep = pte_offset_kernel(&pmd, addr);
+	do {
+		struct page *page, *head;
+		pte_t pte = *ptep;
+
+		if ((pte_val(pte) & mask) != result)
+			return 0;
+		VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
+
+		/* The hugepage case is simplified on sparc64 because
+		 * we encode the sub-page pfn offsets into the
+		 * hugepage PTEs.  We could optimize this in the future
+		 * use page_cache_add_speculative() for the hugepage case.
+		 */
+		page = pte_page(pte);
+		head = compound_head(page);
+		if (!page_cache_get_speculative(head))
+			return 0;
+		if (unlikely(pte_val(pte) != pte_val(*ptep))) {
+			put_page(head);
+			return 0;
+		}
+
+		pages[*nr] = page;
+		(*nr)++;
+	} while (ptep++, addr += PAGE_SIZE, addr != end);
+
+	return 1;
+}
+
+static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end,
+		int write, struct page **pages, int *nr)
+{
+	unsigned long next;
+	pmd_t *pmdp;
+
+	pmdp = pmd_offset(&pud, addr);
+	do {
+		pmd_t pmd = *pmdp;
+
+		next = pmd_addr_end(addr, end);
+		if (pmd_none(pmd))
+			return 0;
+		if (!gup_pte_range(pmd, addr, next, write, pages, nr))
+			return 0;
+	} while (pmdp++, addr = next, addr != end);
+
+	return 1;
+}
+
+static int gup_pud_range(pgd_t pgd, unsigned long addr, unsigned long end,
+		int write, struct page **pages, int *nr)
+{
+	unsigned long next;
+	pud_t *pudp;
+
+	pudp = pud_offset(&pgd, addr);
+	do {
+		pud_t pud = *pudp;
+
+		next = pud_addr_end(addr, end);
+		if (pud_none(pud))
+			return 0;
+		if (!gup_pmd_range(pud, addr, next, write, pages, nr))
+			return 0;
+	} while (pudp++, addr = next, addr != end);
+
+	return 1;
+}
+
+int get_user_pages_fast(unsigned long start, int nr_pages, int write,
+			struct page **pages)
+{
+	struct mm_struct *mm = current->mm;
+	unsigned long addr, len, end;
+	unsigned long next;
+	pgd_t *pgdp;
+	int nr = 0;
+
+	start &= PAGE_MASK;
+	addr = start;
+	len = (unsigned long) nr_pages << PAGE_SHIFT;
+	end = start + len;
+
+	/*
+	 * XXX: batch / limit 'nr', to avoid large irq off latency
+	 * needs some instrumenting to determine the common sizes used by
+	 * important workloads (eg. DB2), and whether limiting the batch size
+	 * will decrease performance.
+	 *
+	 * It seems like we're in the clear for the moment. Direct-IO is
+	 * the main guy that batches up lots of get_user_pages, and even
+	 * they are limited to 64-at-a-time which is not so many.
+	 */
+	/*
+	 * This doesn't prevent pagetable teardown, but does prevent
+	 * the pagetables from being freed on sparc.
+	 *
+	 * So long as we atomically load page table pointers versus teardown,
+	 * we can follow the address down to the the page and take a ref on it.
+	 */
+	local_irq_disable();
+
+	pgdp = pgd_offset(mm, addr);
+	do {
+		pgd_t pgd = *pgdp;
+
+		next = pgd_addr_end(addr, end);
+		if (pgd_none(pgd))
+			goto slow;
+		if (!gup_pud_range(pgd, addr, next, write, pages, &nr))
+			goto slow;
+	} while (pgdp++, addr = next, addr != end);
+
+	local_irq_enable();
+
+	VM_BUG_ON(nr != (end - start) >> PAGE_SHIFT);
+	return nr;
+
+	{
+		int ret;
+
+slow:
+		local_irq_enable();
+
+		/* Try to get the remaining pages with get_user_pages */
+		start += nr << PAGE_SHIFT;
+		pages += nr;
+
+		down_read(&mm->mmap_sem);
+		ret = get_user_pages(current, mm, start,
+			(end - start) >> PAGE_SHIFT, write, 0, pages, NULL);
+		up_read(&mm->mmap_sem);
+
+		/* Have to be a bit careful with return values */
+		if (nr > 0) {
+			if (ret < 0)
+				ret = nr;
+			else
+				ret += nr;
+		}
+
+		return ret;
+	}
+}
diff --git a/arch/sparc/mm/tsb.c b/arch/sparc/mm/tsb.c
index a5f51b2..536412d 100644
--- a/arch/sparc/mm/tsb.c
+++ b/arch/sparc/mm/tsb.c
@@ -236,6 +236,8 @@ static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_idx, unsign
 	}
 }
 
+struct kmem_cache *pgtable_cache __read_mostly;
+
 static struct kmem_cache *tsb_caches[8] __read_mostly;
 
 static const char *tsb_cache_names[8] = {
@@ -253,6 +255,15 @@ void __init pgtable_cache_init(void)
 {
 	unsigned long i;
 
+	pgtable_cache = kmem_cache_create("pgtable_cache",
+					  PAGE_SIZE, PAGE_SIZE,
+					  0,
+					  _clear_page);
+	if (!pgtable_cache) {
+		prom_printf("pgtable_cache_init(): Could not create!\n");
+		prom_halt();
+	}
+
 	for (i = 0; i < 8; i++) {
 		unsigned long size = 8192 << i;
 		const char *name = tsb_cache_names[i];
diff --git a/arch/um/Kconfig.x86 b/arch/um/Kconfig.x86
index 8aae429..d31ecf3 100644
--- a/arch/um/Kconfig.x86
+++ b/arch/um/Kconfig.x86
@@ -1,3 +1,5 @@
+mainmenu "User Mode Linux/$SUBARCH $KERNELVERSION Kernel Configuration"
+
 source "arch/um/Kconfig.common"
 
 menu "UML-specific options"
diff --git a/arch/um/drivers/chan_kern.c b/arch/um/drivers/chan_kern.c
index 25e1965..d4191fe 100644
--- a/arch/um/drivers/chan_kern.c
+++ b/arch/um/drivers/chan_kern.c
@@ -543,11 +543,10 @@ int parse_chan_pair(char *str, struct line *line, int device,
 		    const struct chan_opts *opts, char **error_out)
 {
 	struct list_head *chans = &line->chan_list;
-	struct chan *new, *chan;
+	struct chan *new;
 	char *in, *out;
 
 	if (!list_empty(chans)) {
-		chan = list_entry(chans->next, struct chan, list);
 		free_chan(chans, 0);
 		INIT_LIST_HEAD(chans);
 	}
diff --git a/arch/um/drivers/cow_user.c b/arch/um/drivers/cow_user.c
index 93f227a..9cbb426 100644
--- a/arch/um/drivers/cow_user.c
+++ b/arch/um/drivers/cow_user.c
@@ -186,7 +186,11 @@ static int absolutize(char *to, int size, char *from)
 		strcat(to, "/");
 		strcat(to, from);
 	}
-	chdir(save_cwd);
+	if (chdir(save_cwd)) {
+		cow_printf("absolutize : Can't cd to '%s' - "
+			   "errno = %d\n", save_cwd, errno);
+		return -1;
+	}
 	return 0;
 }
 
diff --git a/arch/um/drivers/harddog_user.c b/arch/um/drivers/harddog_user.c
index b56f8e0..84dce3f 100644
--- a/arch/um/drivers/harddog_user.c
+++ b/arch/um/drivers/harddog_user.c
@@ -32,7 +32,7 @@ int start_watchdog(int *in_fd_ret, int *out_fd_ret, char *sock)
 {
 	struct dog_data data;
 	int in_fds[2], out_fds[2], pid, n, err;
-	char pid_buf[sizeof("nnnnn\0")], c;
+	char pid_buf[sizeof("nnnnnnn\0")], c;
 	char *pid_args[] = { "/usr/bin/uml_watchdog", "-pid", pid_buf, NULL };
 	char *mconsole_args[] = { "/usr/bin/uml_watchdog", "-mconsole", NULL,
 				  NULL };
diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c
index 35dd0b8..d51c404 100644
--- a/arch/um/drivers/line.c
+++ b/arch/um/drivers/line.c
@@ -176,10 +176,9 @@ void line_flush_buffer(struct tty_struct *tty)
 {
 	struct line *line = tty->driver_data;
 	unsigned long flags;
-	int err;
 
 	spin_lock_irqsave(&line->lock, flags);
-	err = flush_buffer(line);
+	flush_buffer(line);
 	spin_unlock_irqrestore(&line->lock, flags);
 }
 
diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c
index 47d0c37..22745b4 100644
--- a/arch/um/drivers/net_kern.c
+++ b/arch/um/drivers/net_kern.c
@@ -262,6 +262,15 @@ static int uml_net_change_mtu(struct net_device *dev, int new_mtu)
 	return 0;
 }
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void uml_net_poll_controller(struct net_device *dev)
+{
+	disable_irq(dev->irq);
+	uml_net_interrupt(dev->irq, dev);
+	enable_irq(dev->irq);
+}
+#endif
+
 static void uml_net_get_drvinfo(struct net_device *dev,
 				struct ethtool_drvinfo *info)
 {
@@ -364,6 +373,9 @@ static const struct net_device_ops uml_netdev_ops = {
 	.ndo_set_mac_address	= eth_mac_addr,
 	.ndo_change_mtu 	= uml_net_change_mtu,
 	.ndo_validate_addr	= eth_validate_addr,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_poll_controller = uml_net_poll_controller,
+#endif
 };
 
 /*
diff --git a/arch/um/drivers/net_user.c b/arch/um/drivers/net_user.c
index 9415dd9..5201188 100644
--- a/arch/um/drivers/net_user.c
+++ b/arch/um/drivers/net_user.c
@@ -228,7 +228,10 @@ static void change(char *dev, char *what, unsigned char *addr,
 		       "buffer\n");
 
 	pid = change_tramp(argv, output, output_len);
-	if (pid < 0) return;
+	if (pid < 0) {
+		kfree(output);
+		return;
+	}
 
 	if (output != NULL) {
 		printk("%s", output);
diff --git a/arch/um/drivers/slip_user.c b/arch/um/drivers/slip_user.c
index a1c2d2c..cbacfc4 100644
--- a/arch/um/drivers/slip_user.c
+++ b/arch/um/drivers/slip_user.c
@@ -102,7 +102,7 @@ static int slip_tramp(char **argv, int fd)
 		       "buffer\n");
 		os_kill_process(pid, 1);
 		err = -ENOMEM;
-		goto out_free;
+		goto out_close;
 	}
 
 	close(fds[1]);
@@ -112,7 +112,6 @@ static int slip_tramp(char **argv, int fd)
 	err = helper_wait(pid);
 	close(fds[0]);
 
-out_free:
 	kfree(output);
 	return err;
 
diff --git a/arch/um/include/asm/delay.h b/arch/um/include/asm/delay.h
index c71e32b..8a5576d 100644
--- a/arch/um/include/asm/delay.h
+++ b/arch/um/include/asm/delay.h
@@ -1,20 +1,18 @@
 #ifndef __UM_DELAY_H
 #define __UM_DELAY_H
 
-#define MILLION 1000000
-
 /* Undefined on purpose */
 extern void __bad_udelay(void);
+extern void __bad_ndelay(void);
 
 extern void __udelay(unsigned long usecs);
+extern void __ndelay(unsigned long usecs);
 extern void __delay(unsigned long loops);
 
 #define udelay(n) ((__builtin_constant_p(n) && (n) > 20000) ? \
 	__bad_udelay() : __udelay(n))
 
-/* It appears that ndelay is not used at all for UML, and has never been
- * implemented. */
-extern void __unimplemented_ndelay(void);
-#define ndelay(n) __unimplemented_ndelay()
+#define ndelay(n) ((__builtin_constant_p(n) && (n) > 20000) ? \
+	__bad_ndelay() : __ndelay(n))
 
 #endif
diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c
index 09bd7b5..939a4a6 100644
--- a/arch/um/kernel/exec.c
+++ b/arch/um/kernel/exec.c
@@ -38,7 +38,6 @@ void flush_thread(void)
 
 void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp)
 {
-	set_fs(USER_DS);
 	PT_REGS_IP(regs) = eip;
 	PT_REGS_SP(regs) = esp;
 }
diff --git a/arch/um/kernel/reboot.c b/arch/um/kernel/reboot.c
index 869bec9..4d93dff 100644
--- a/arch/um/kernel/reboot.c
+++ b/arch/um/kernel/reboot.c
@@ -20,9 +20,8 @@ static void kill_off_processes(void)
 		os_kill_ptraced_process(userspace_pid[0], 1);
 	else {
 		struct task_struct *p;
-		int pid, me;
+		int pid;
 
-		me = os_getpid();
 		for_each_process(p) {
 			if (p->mm == NULL)
 				continue;
diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile
index d66f038..b33f4df 100644
--- a/arch/um/os-Linux/Makefile
+++ b/arch/um/os-Linux/Makefile
@@ -3,10 +3,12 @@
 # Licensed under the GPL
 #
 
-obj-y = aio.o elf_aux.o execvp.o file.o helper.o irq.o main.o mem.o process.o \
+obj-y = aio.o execvp.o file.o helper.o irq.o main.o mem.o process.o \
 	registers.o sigio.o signal.o start_up.o time.o tty.o uaccess.o \
 	umid.o tls.o user_syms.o util.o drivers/ sys-$(SUBARCH)/ skas/
 
+obj-$(CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA) += elf_aux.o
+
 USER_OBJS := $(user-objs-y) aio.o elf_aux.o execvp.o file.o helper.o irq.o \
 	main.o mem.o process.o registers.o sigio.o signal.o start_up.o time.o \
 	tty.o tls.o uaccess.o umid.o util.o
diff --git a/arch/um/os-Linux/elf_aux.c b/arch/um/os-Linux/elf_aux.c
index 608784d..9533237 100644
--- a/arch/um/os-Linux/elf_aux.c
+++ b/arch/um/os-Linux/elf_aux.c
@@ -14,16 +14,11 @@
 #include "mem_user.h"
 #include <kern_constants.h>
 
-/* Use the one from the kernel - the host may miss it, if having old headers. */
-#if UM_ELF_CLASS == UM_ELFCLASS32
 typedef Elf32_auxv_t elf_auxv_t;
-#else
-typedef Elf64_auxv_t elf_auxv_t;
-#endif
 
 /* These are initialized very early in boot and never changed */
 char * elf_aux_platform;
-long elf_aux_hwcap;
+extern long elf_aux_hwcap;
 unsigned long vsyscall_ehdr;
 unsigned long vsyscall_end;
 unsigned long __kernel_vsyscall;
diff --git a/arch/um/os-Linux/helper.c b/arch/um/os-Linux/helper.c
index b6b1096..feff22d 100644
--- a/arch/um/os-Linux/helper.c
+++ b/arch/um/os-Linux/helper.c
@@ -28,14 +28,14 @@ static int helper_child(void *arg)
 {
 	struct helper_data *data = arg;
 	char **argv = data->argv;
-	int err;
+	int err, ret;
 
 	if (data->pre_exec != NULL)
 		(*data->pre_exec)(data->pre_data);
 	err = execvp_noalloc(data->buf, argv[0], argv);
 
 	/* If the exec succeeds, we don't get here */
-	write(data->fd, &err, sizeof(err));
+	CATCH_EINTR(ret = write(data->fd, &err, sizeof(err)));
 
 	return 0;
 }
diff --git a/arch/um/os-Linux/main.c b/arch/um/os-Linux/main.c
index fb2a97a..8471b81 100644
--- a/arch/um/os-Linux/main.c
+++ b/arch/um/os-Linux/main.c
@@ -21,6 +21,8 @@
 #define STACKSIZE (8 * 1024 * 1024)
 #define THREAD_NAME_LEN (256)
 
+long elf_aux_hwcap;
+
 static void set_stklim(void)
 {
 	struct rlimit lim;
@@ -143,7 +145,9 @@ int __init main(int argc, char **argv, char **envp)
 	install_fatal_handler(SIGINT);
 	install_fatal_handler(SIGTERM);
 
+#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
 	scan_elf_aux(envp);
+#endif
 
 	do_uml_initcalls();
 	ret = linux_main(argc, argv);
diff --git a/arch/um/os-Linux/mem.c b/arch/um/os-Linux/mem.c
index e696144..62878cf 100644
--- a/arch/um/os-Linux/mem.c
+++ b/arch/um/os-Linux/mem.c
@@ -176,7 +176,7 @@ static int __init make_tempfile(const char *template, char **out_tempname,
 
 	find_tempdir();
 	if ((tempdir == NULL) || (strlen(tempdir) >= MAXPATHLEN))
-		return -1;
+		goto out;
 
 	if (template[0] != '/')
 		strcpy(tempname, tempdir);
@@ -191,13 +191,15 @@ static int __init make_tempfile(const char *template, char **out_tempname,
 	}
 	if (do_unlink && (unlink(tempname) < 0)) {
 		perror("unlink");
-		goto out;
+		goto close;
 	}
 	if (out_tempname) {
 		*out_tempname = tempname;
 	} else
 		free(tempname);
 	return fd;
+close:
+	close(fd);
 out:
 	free(tempname);
 	return -1;
diff --git a/arch/um/os-Linux/user_syms.c b/arch/um/os-Linux/user_syms.c
index 05f5ea8..45ffe46 100644
--- a/arch/um/os-Linux/user_syms.c
+++ b/arch/um/os-Linux/user_syms.c
@@ -113,3 +113,8 @@ EXPORT_SYMBOL(__stack_smash_handler);
 
 extern long __guard __attribute__((weak));
 EXPORT_SYMBOL(__guard);
+
+#ifdef _FORTIFY_SOURCE
+extern int __sprintf_chk(char *str, int flag, size_t strlen, const char *format);
+EXPORT_SYMBOL(__sprintf_chk);
+#endif
diff --git a/arch/um/sys-i386/Makefile b/arch/um/sys-i386/Makefile
index 87b659d..3923cfb 100644
--- a/arch/um/sys-i386/Makefile
+++ b/arch/um/sys-i386/Makefile
@@ -4,7 +4,7 @@
 
 obj-y = bug.o bugs.o checksum.o delay.o fault.o ksyms.o ldt.o ptrace.o \
 	ptrace_user.o setjmp.o signal.o stub.o stub_segv.o syscalls.o sysrq.o \
-	sys_call_table.o tls.o atomic64_cx8_32.o
+	sys_call_table.o tls.o atomic64_cx8_32.o mem.o
 
 obj-$(CONFIG_BINFMT_ELF) += elfcore.o
 
diff --git a/arch/um/sys-i386/asm/elf.h b/arch/um/sys-i386/asm/elf.h
index d964a41..4230555 100644
--- a/arch/um/sys-i386/asm/elf.h
+++ b/arch/um/sys-i386/asm/elf.h
@@ -105,6 +105,8 @@ extern unsigned long __kernel_vsyscall;
 #define FIXADDR_USER_START      VSYSCALL_BASE
 #define FIXADDR_USER_END        VSYSCALL_END
 
+#define __HAVE_ARCH_GATE_AREA 1
+
 /*
  * Architecture-neutral AT_ values in 0-17, leave some room
  * for more of them, start the x86-specific ones at 32.
diff --git a/arch/um/sys-i386/delay.c b/arch/um/sys-i386/delay.c
index d623e07..f3fe1a6 100644
--- a/arch/um/sys-i386/delay.c
+++ b/arch/um/sys-i386/delay.c
@@ -1,29 +1,60 @@
+/*
+ * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
+ * Mostly copied from arch/x86/lib/delay.c
+ *
+ * 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/module.h>
 #include <linux/kernel.h>
 #include <linux/delay.h>
 #include <asm/param.h>
 
-void __delay(unsigned long time)
+void __delay(unsigned long loops)
 {
-	/* Stolen from the i386 __loop_delay */
-	int d0;
-	__asm__ __volatile__(
-		"\tjmp 1f\n"
+	asm volatile(
+		"test %0,%0\n"
+		"jz 3f\n"
+		"jmp 1f\n"
+
 		".align 16\n"
-		"1:\tjmp 2f\n"
+		"1: jmp 2f\n"
+
 		".align 16\n"
-		"2:\tdecl %0\n\tjns 2b"
-		:"=&a" (d0)
-		:"0" (time));
+		"2: dec %0\n"
+		" jnz 2b\n"
+		"3: dec %0\n"
+
+		: /* we don't need output */
+		: "a" (loops)
+	);
 }
+EXPORT_SYMBOL(__delay);
 
-void __udelay(unsigned long usecs)
+inline void __const_udelay(unsigned long xloops)
 {
-	int i, n;
+	int d0;
 
-	n = (loops_per_jiffy * HZ * usecs) / MILLION;
-        for(i=0;i<n;i++)
-                cpu_relax();
+	xloops *= 4;
+	asm("mull %%edx"
+		: "=d" (xloops), "=&a" (d0)
+		: "1" (xloops), "0"
+		(loops_per_jiffy * (HZ/4)));
+
+	__delay(++xloops);
 }
+EXPORT_SYMBOL(__const_udelay);
 
+void __udelay(unsigned long usecs)
+{
+	__const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
+}
 EXPORT_SYMBOL(__udelay);
+
+void __ndelay(unsigned long nsecs)
+{
+	__const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
+}
+EXPORT_SYMBOL(__ndelay);
diff --git a/arch/um/sys-i386/mem.c b/arch/um/sys-i386/mem.c
new file mode 100644
index 0000000..639900a
--- /dev/null
+++ b/arch/um/sys-i386/mem.c
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
+ *
+ * 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/mm.h>
+#include <asm/page.h>
+#include <asm/mman.h>
+
+static struct vm_area_struct gate_vma;
+
+static int __init gate_vma_init(void)
+{
+	if (!FIXADDR_USER_START)
+		return 0;
+
+	gate_vma.vm_mm = NULL;
+	gate_vma.vm_start = FIXADDR_USER_START;
+	gate_vma.vm_end = FIXADDR_USER_END;
+	gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
+	gate_vma.vm_page_prot = __P101;
+
+	/*
+	 * Make sure the vDSO gets into every core dump.
+	 * Dumping its contents makes post-mortem fully interpretable later
+	 * without matching up the same kernel and hardware config to see
+	 * what PC values meant.
+	 */
+	gate_vma.vm_flags |= VM_ALWAYSDUMP;
+
+	return 0;
+}
+__initcall(gate_vma_init);
+
+struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
+{
+	return FIXADDR_USER_START ? &gate_vma : NULL;
+}
+
+int in_gate_area_no_mm(unsigned long addr)
+{
+	if (!FIXADDR_USER_START)
+		return 0;
+
+	if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END))
+		return 1;
+
+	return 0;
+}
+
+int in_gate_area(struct mm_struct *mm, unsigned long addr)
+{
+	struct vm_area_struct *vma = get_gate_vma(mm);
+
+	if (!vma)
+		return 0;
+
+	return (addr >= vma->vm_start) && (addr < vma->vm_end);
+}
diff --git a/arch/um/sys-x86_64/Makefile b/arch/um/sys-x86_64/Makefile
index 61fc99a..bd4d1d3 100644
--- a/arch/um/sys-x86_64/Makefile
+++ b/arch/um/sys-x86_64/Makefile
@@ -4,10 +4,12 @@
 # Licensed under the GPL
 #
 
-obj-y = bug.o bugs.o delay.o fault.o ldt.o mem.o ptrace.o ptrace_user.o \
+obj-y = bug.o bugs.o delay.o fault.o ldt.o ptrace.o ptrace_user.o mem.o \
 	setjmp.o signal.o stub.o stub_segv.o syscalls.o syscall_table.o \
 	sysrq.o ksyms.o tls.o
 
+obj-y += vdso/
+
 subarch-obj-y = lib/csum-partial_64.o lib/memcpy_64.o lib/thunk_64.o \
 		lib/rwsem.o
 subarch-obj-$(CONFIG_MODULES) += kernel/module.o
diff --git a/arch/um/sys-x86_64/asm/elf.h b/arch/um/sys-x86_64/asm/elf.h
index d6d5af3..11a2bfb 100644
--- a/arch/um/sys-x86_64/asm/elf.h
+++ b/arch/um/sys-x86_64/asm/elf.h
@@ -119,4 +119,14 @@ extern long elf_aux_hwcap;
 
 #define SET_PERSONALITY(ex) do ; while(0)
 
+#define __HAVE_ARCH_GATE_AREA 1
+#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
+struct linux_binprm;
+extern int arch_setup_additional_pages(struct linux_binprm *bprm,
+	int uses_interp);
+
+extern unsigned long um_vdso_addr;
+#define AT_SYSINFO_EHDR 33
+#define ARCH_DLINFO	NEW_AUX_ENT(AT_SYSINFO_EHDR, um_vdso_addr)
+
 #endif
diff --git a/arch/um/sys-x86_64/delay.c b/arch/um/sys-x86_64/delay.c
index dee5be6..f3fe1a6 100644
--- a/arch/um/sys-x86_64/delay.c
+++ b/arch/um/sys-x86_64/delay.c
@@ -1,30 +1,60 @@
 /*
- * Copyright 2003 PathScale, Inc.
- * Copied from arch/x86_64
+ * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
+ * Mostly copied from arch/x86/lib/delay.c
  *
- * Licensed under the GPL
+ * 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/module.h>
+#include <linux/kernel.h>
 #include <linux/delay.h>
-#include <asm/processor.h>
 #include <asm/param.h>
 
 void __delay(unsigned long loops)
 {
-	unsigned long i;
+	asm volatile(
+		"test %0,%0\n"
+		"jz 3f\n"
+		"jmp 1f\n"
 
-        for(i = 0; i < loops; i++)
-                cpu_relax();
+		".align 16\n"
+		"1: jmp 2f\n"
+
+		".align 16\n"
+		"2: dec %0\n"
+		" jnz 2b\n"
+		"3: dec %0\n"
+
+		: /* we don't need output */
+		: "a" (loops)
+	);
 }
+EXPORT_SYMBOL(__delay);
 
-void __udelay(unsigned long usecs)
+inline void __const_udelay(unsigned long xloops)
 {
-	unsigned long i, n;
+	int d0;
 
-	n = (loops_per_jiffy * HZ * usecs) / MILLION;
-        for(i=0;i<n;i++)
-                cpu_relax();
+	xloops *= 4;
+	asm("mull %%edx"
+		: "=d" (xloops), "=&a" (d0)
+		: "1" (xloops), "0"
+		(loops_per_jiffy * (HZ/4)));
+
+	__delay(++xloops);
 }
+EXPORT_SYMBOL(__const_udelay);
 
+void __udelay(unsigned long usecs)
+{
+	__const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
+}
 EXPORT_SYMBOL(__udelay);
+
+void __ndelay(unsigned long nsecs)
+{
+	__const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
+}
+EXPORT_SYMBOL(__ndelay);
diff --git a/arch/um/sys-x86_64/mem.c b/arch/um/sys-x86_64/mem.c
index 3f8df8a..5465187 100644
--- a/arch/um/sys-x86_64/mem.c
+++ b/arch/um/sys-x86_64/mem.c
@@ -1,16 +1,26 @@
-/*
- * Copyright 2003 PathScale, Inc.
- *
- * Licensed under the GPL
- */
-
 #include "linux/mm.h"
 #include "asm/page.h"
 #include "asm/mman.h"
 
-unsigned long vm_stack_flags = __VM_STACK_FLAGS;
-unsigned long vm_stack_flags32 = __VM_STACK_FLAGS;
-unsigned long vm_data_default_flags = __VM_DATA_DEFAULT_FLAGS;
-unsigned long vm_data_default_flags32 = __VM_DATA_DEFAULT_FLAGS;
-unsigned long vm_force_exec32 = PROT_EXEC;
+const char *arch_vma_name(struct vm_area_struct *vma)
+{
+	if (vma->vm_mm && vma->vm_start == um_vdso_addr)
+		return "[vdso]";
+
+	return NULL;
+}
+
+struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
+{
+	return NULL;
+}
+
+int in_gate_area(struct mm_struct *mm, unsigned long addr)
+{
+	return 0;
+}
 
+int in_gate_area_no_mm(unsigned long addr)
+{
+	return 0;
+}
diff --git a/arch/um/sys-x86_64/shared/sysdep/vm-flags.h b/arch/um/sys-x86_64/shared/sysdep/vm-flags.h
index 3213edf..3978e55 100644
--- a/arch/um/sys-x86_64/shared/sysdep/vm-flags.h
+++ b/arch/um/sys-x86_64/shared/sysdep/vm-flags.h
@@ -7,27 +7,9 @@
 #ifndef __VM_FLAGS_X86_64_H
 #define __VM_FLAGS_X86_64_H
 
-#define __VM_DATA_DEFAULT_FLAGS	(VM_READ | VM_WRITE | VM_EXEC | \
-				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
-#define __VM_STACK_FLAGS 	(VM_GROWSDOWN | VM_READ | VM_WRITE | \
-				 VM_EXEC | VM_MAYREAD | VM_MAYWRITE | \
-				 VM_MAYEXEC)
-
-extern unsigned long vm_stack_flags, vm_stack_flags32;
-extern unsigned long vm_data_default_flags, vm_data_default_flags32;
-extern unsigned long vm_force_exec32;
-
-#ifdef TIF_IA32
-#define VM_DATA_DEFAULT_FLAGS \
-	(test_thread_flag(TIF_IA32) ? vm_data_default_flags32 : \
-	  vm_data_default_flags)
-
-#define VM_STACK_DEFAULT_FLAGS \
-	(test_thread_flag(TIF_IA32) ? vm_stack_flags32 : vm_stack_flags)
-#endif
-
-#define VM_DATA_DEFAULT_FLAGS vm_data_default_flags
-
-#define VM_STACK_DEFAULT_FLAGS vm_stack_flags
+#define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | VM_EXEC | \
+	VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+#define VM_STACK_DEFAULT_FLAGS (VM_GROWSDOWN | VM_READ | VM_WRITE | \
+	VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
 
 #endif
diff --git a/arch/um/sys-x86_64/vdso/Makefile b/arch/um/sys-x86_64/vdso/Makefile
new file mode 100644
index 0000000..5dffe6d
--- /dev/null
+++ b/arch/um/sys-x86_64/vdso/Makefile
@@ -0,0 +1,90 @@
+#
+# Building vDSO images for x86.
+#
+
+VDSO64-y		:= y
+
+vdso-install-$(VDSO64-y)	+= vdso.so
+
+
+# files to link into the vdso
+vobjs-y := vdso-note.o um_vdso.o
+
+# files to link into kernel
+obj-$(VDSO64-y)			+= vdso.o vma.o
+
+vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
+
+$(obj)/vdso.o: $(obj)/vdso.so
+
+targets += vdso.so vdso.so.dbg vdso.lds $(vobjs-y)
+
+export CPPFLAGS_vdso.lds += -P -C
+
+VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \
+       -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096
+
+$(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so
+
+$(obj)/vdso.so.dbg: $(src)/vdso.lds $(vobjs) FORCE
+	$(call if_changed,vdso)
+
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg FORCE
+	$(call if_changed,objcopy)
+
+#
+# Don't omit frame pointers for ease of userspace debugging, but do
+# optimize sibling calls.
+#
+CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
+       $(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \
+       -fno-omit-frame-pointer -foptimize-sibling-calls
+
+$(vobjs): KBUILD_CFLAGS += $(CFL)
+
+#
+# vDSO code runs in userspace and -pg doesn't help with profiling anyway.
+#
+CFLAGS_REMOVE_vdso-note.o = -pg
+CFLAGS_REMOVE_um_vdso.o = -pg
+
+targets += vdso-syms.lds
+obj-$(VDSO64-y)			+= vdso-syms.lds
+
+#
+# Match symbols in the DSO that look like VDSO*; produce a file of constants.
+#
+sed-vdsosym := -e 's/^00*/0/' \
+	-e 's/^\([0-9a-fA-F]*\) . \(VDSO[a-zA-Z0-9_]*\)$$/\2 = 0x\1;/p'
+quiet_cmd_vdsosym = VDSOSYM $@
+define cmd_vdsosym
+	$(NM) $< | LC_ALL=C sed -n $(sed-vdsosym) | LC_ALL=C sort > $@
+endef
+
+$(obj)/%-syms.lds: $(obj)/%.so.dbg FORCE
+	$(call if_changed,vdsosym)
+
+#
+# The DSO images are built using a special linker script.
+#
+quiet_cmd_vdso = VDSO    $@
+      cmd_vdso = $(CC) -nostdlib -o $@ \
+		       $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \
+		       -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \
+		 sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'
+
+VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
+GCOV_PROFILE := n
+
+#
+# Install the unstripped copy of vdso*.so listed in $(vdso-install-y).
+#
+quiet_cmd_vdso_install = INSTALL $@
+      cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
+$(vdso-install-y): %.so: $(obj)/%.so.dbg FORCE
+	@mkdir -p $(MODLIB)/vdso
+	$(call cmd,vdso_install)
+
+PHONY += vdso_install $(vdso-install-y)
+vdso_install: $(vdso-install-y)
diff --git a/arch/um/sys-x86_64/vdso/checkundef.sh b/arch/um/sys-x86_64/vdso/checkundef.sh
new file mode 100644
index 0000000..7ee90a9
--- /dev/null
+++ b/arch/um/sys-x86_64/vdso/checkundef.sh
@@ -0,0 +1,10 @@
+#!/bin/sh
+nm="$1"
+file="$2"
+$nm "$file" | grep '^ *U' > /dev/null 2>&1
+if [ $? -eq 1 ]; then
+    exit 0
+else
+    echo "$file: undefined symbols found" >&2
+    exit 1
+fi
diff --git a/arch/um/sys-x86_64/vdso/um_vdso.c b/arch/um/sys-x86_64/vdso/um_vdso.c
new file mode 100644
index 0000000..7c441b5
--- /dev/null
+++ b/arch/um/sys-x86_64/vdso/um_vdso.c
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
+ *
+ * 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.
+ *
+ * This vDSO turns all calls into a syscall so that UML can trap them.
+ */
+
+
+/* Disable profiling for userspace code */
+#define DISABLE_BRANCH_PROFILING
+
+#include <linux/time.h>
+#include <linux/getcpu.h>
+#include <asm/unistd.h>
+
+int __vdso_clock_gettime(clockid_t clock, struct timespec *ts)
+{
+	long ret;
+
+	asm("syscall" : "=a" (ret) :
+		"0" (__NR_clock_gettime), "D" (clock), "S" (ts) : "memory");
+
+	return ret;
+}
+int clock_gettime(clockid_t, struct timespec *)
+	__attribute__((weak, alias("__vdso_clock_gettime")));
+
+int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
+{
+	long ret;
+
+	asm("syscall" : "=a" (ret) :
+		"0" (__NR_gettimeofday), "D" (tv), "S" (tz) : "memory");
+
+	return ret;
+}
+int gettimeofday(struct timeval *, struct timezone *)
+	__attribute__((weak, alias("__vdso_gettimeofday")));
+
+time_t __vdso_time(time_t *t)
+{
+	long secs;
+
+	asm volatile("syscall"
+		: "=a" (secs)
+		: "0" (__NR_time), "D" (t) : "cc", "r11", "cx", "memory");
+
+	return secs;
+}
+int time(time_t *t) __attribute__((weak, alias("__vdso_time")));
+
+long
+__vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused)
+{
+	/*
+	 * UML does not support SMP, we can cheat here. :)
+	 */
+
+	if (cpu)
+		*cpu = 0;
+	if (node)
+		*node = 0;
+
+	return 0;
+}
+
+long getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache)
+	__attribute__((weak, alias("__vdso_getcpu")));
diff --git a/arch/um/sys-x86_64/vdso/vdso-layout.lds.S b/arch/um/sys-x86_64/vdso/vdso-layout.lds.S
new file mode 100644
index 0000000..634a2cf
--- /dev/null
+++ b/arch/um/sys-x86_64/vdso/vdso-layout.lds.S
@@ -0,0 +1,64 @@
+/*
+ * Linker script for vDSO.  This is an ELF shared object prelinked to
+ * its virtual address, and with only one read-only segment.
+ * This script controls its layout.
+ */
+
+SECTIONS
+{
+	. = VDSO_PRELINK + SIZEOF_HEADERS;
+
+	.hash		: { *(.hash) }			:text
+	.gnu.hash	: { *(.gnu.hash) }
+	.dynsym		: { *(.dynsym) }
+	.dynstr		: { *(.dynstr) }
+	.gnu.version	: { *(.gnu.version) }
+	.gnu.version_d	: { *(.gnu.version_d) }
+	.gnu.version_r	: { *(.gnu.version_r) }
+
+	.note		: { *(.note.*) }		:text	:note
+
+	.eh_frame_hdr	: { *(.eh_frame_hdr) }		:text	:eh_frame_hdr
+	.eh_frame	: { KEEP (*(.eh_frame)) }	:text
+
+	.dynamic	: { *(.dynamic) }		:text	:dynamic
+
+	.rodata		: { *(.rodata*) }		:text
+	.data		: {
+	      *(.data*)
+	      *(.sdata*)
+	      *(.got.plt) *(.got)
+	      *(.gnu.linkonce.d.*)
+	      *(.bss*)
+	      *(.dynbss*)
+	      *(.gnu.linkonce.b.*)
+	}
+
+	.altinstructions	: { *(.altinstructions) }
+	.altinstr_replacement	: { *(.altinstr_replacement) }
+
+	/*
+	 * Align the actual code well away from the non-instruction data.
+	 * This is the best thing for the I-cache.
+	 */
+	. = ALIGN(0x100);
+
+	.text		: { *(.text*) }			:text	=0x90909090
+}
+
+/*
+ * Very old versions of ld do not recognize this name token; use the constant.
+ */
+#define PT_GNU_EH_FRAME	0x6474e550
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+	text		PT_LOAD		FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
+	dynamic		PT_DYNAMIC	FLAGS(4);		/* PF_R */
+	note		PT_NOTE		FLAGS(4);		/* PF_R */
+	eh_frame_hdr	PT_GNU_EH_FRAME;
+}
diff --git a/arch/um/sys-x86_64/vdso/vdso-note.S b/arch/um/sys-x86_64/vdso/vdso-note.S
new file mode 100644
index 0000000..79a071e
--- /dev/null
+++ b/arch/um/sys-x86_64/vdso/vdso-note.S
@@ -0,0 +1,12 @@
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+#include <linux/elfnote.h>
+
+ELFNOTE_START(Linux, 0, "a")
+	.long LINUX_VERSION_CODE
+ELFNOTE_END
diff --git a/arch/um/sys-x86_64/vdso/vdso.S b/arch/um/sys-x86_64/vdso/vdso.S
new file mode 100644
index 0000000..ec82c16
--- /dev/null
+++ b/arch/um/sys-x86_64/vdso/vdso.S
@@ -0,0 +1,10 @@
+#include <linux/init.h>
+
+__INITDATA
+
+	.globl vdso_start, vdso_end
+vdso_start:
+	.incbin "arch/um/sys-x86_64/vdso/vdso.so"
+vdso_end:
+
+__FINIT
diff --git a/arch/um/sys-x86_64/vdso/vdso.lds.S b/arch/um/sys-x86_64/vdso/vdso.lds.S
new file mode 100644
index 0000000..b96b267
--- /dev/null
+++ b/arch/um/sys-x86_64/vdso/vdso.lds.S
@@ -0,0 +1,32 @@
+/*
+ * Linker script for 64-bit vDSO.
+ * We #include the file to define the layout details.
+ * Here we only choose the prelinked virtual address.
+ *
+ * This file defines the version script giving the user-exported symbols in
+ * the DSO.  We can define local symbols here called VDSO* to make their
+ * values visible using the asm-x86/vdso.h macros from the kernel proper.
+ */
+
+#define VDSO_PRELINK 0xffffffffff700000
+#include "vdso-layout.lds.S"
+
+/*
+ * This controls what userland symbols we export from the vDSO.
+ */
+VERSION {
+	LINUX_2.6 {
+	global:
+		clock_gettime;
+		__vdso_clock_gettime;
+		gettimeofday;
+		__vdso_gettimeofday;
+		getcpu;
+		__vdso_getcpu;
+		time;
+		__vdso_time;
+	local: *;
+	};
+}
+
+VDSO64_PRELINK = VDSO_PRELINK;
diff --git a/arch/um/sys-x86_64/vdso/vma.c b/arch/um/sys-x86_64/vdso/vma.c
new file mode 100644
index 0000000..9495c8d
--- /dev/null
+++ b/arch/um/sys-x86_64/vdso/vma.c
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
+ *
+ * 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/slab.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <asm/page.h>
+#include <linux/init.h>
+
+unsigned int __read_mostly vdso_enabled = 1;
+unsigned long um_vdso_addr;
+
+extern unsigned long task_size;
+extern char vdso_start[], vdso_end[];
+
+static struct page **vdsop;
+
+static int __init init_vdso(void)
+{
+	struct page *um_vdso;
+
+	BUG_ON(vdso_end - vdso_start > PAGE_SIZE);
+
+	um_vdso_addr = task_size - PAGE_SIZE;
+
+	vdsop = kmalloc(GFP_KERNEL, sizeof(struct page *));
+	if (!vdsop)
+		goto oom;
+
+	um_vdso = alloc_page(GFP_KERNEL);
+	if (!um_vdso) {
+		kfree(vdsop);
+
+		goto oom;
+	}
+
+	copy_page(page_address(um_vdso), vdso_start);
+	*vdsop = um_vdso;
+
+	return 0;
+
+oom:
+	printk(KERN_ERR "Cannot allocate vdso\n");
+	vdso_enabled = 0;
+
+	return -ENOMEM;
+}
+subsys_initcall(init_vdso);
+
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+	int err;
+	struct mm_struct *mm = current->mm;
+
+	if (!vdso_enabled)
+		return 0;
+
+	down_write(&mm->mmap_sem);
+
+	err = install_special_mapping(mm, um_vdso_addr, PAGE_SIZE,
+		VM_READ|VM_EXEC|
+		VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
+		VM_ALWAYSDUMP,
+		vdsop);
+
+	up_write(&mm->mmap_sem);
+
+	return err;
+}
diff --git a/arch/xtensa/include/asm/uaccess.h b/arch/xtensa/include/asm/uaccess.h
index 82d4e38..3fa526f 100644
--- a/arch/xtensa/include/asm/uaccess.h
+++ b/arch/xtensa/include/asm/uaccess.h
@@ -17,6 +17,7 @@
 #define _XTENSA_UACCESS_H
 
 #include <linux/errno.h>
+#include <linux/prefetch.h>
 #include <asm/types.h>
 
 #define VERIFY_READ    0
diff --git a/arch/xtensa/kernel/ptrace.c b/arch/xtensa/kernel/ptrace.c
index c72c947..a0d042a 100644
--- a/arch/xtensa/kernel/ptrace.c
+++ b/arch/xtensa/kernel/ptrace.c
@@ -147,6 +147,9 @@ int ptrace_setxregs(struct task_struct *child, void __user *uregs)
 	elf_xtregs_t *xtregs = uregs;
 	int ret = 0;
 
+	if (!access_ok(VERIFY_READ, uregs, sizeof(elf_xtregs_t)))
+		return -EFAULT;
+
 #if XTENSA_HAVE_COPROCESSORS
 	/* Flush all coprocessors before we overwrite them. */
 	coprocessor_flush_all(ti);