Merge commit 'v2.6.26-rc8' into x86/mce

48 files changed, 351 insertions, 266 deletions

diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index dba8e05f028..6976812cfb1 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -259,6 +259,8 @@ if BROKEN
 	source "drivers/mtd/Kconfig"
 endif
 
+source "drivers/leds/Kconfig"
+
 #This is just to shut up some Kconfig warnings, so no prompt.
 config INPUT
 	bool
diff --git a/arch/um/Kconfig.char b/arch/um/Kconfig.char
index 3a4b396d797..1b238ebae6b 100644
--- a/arch/um/Kconfig.char
+++ b/arch/um/Kconfig.char
@@ -145,14 +145,14 @@ config LEGACY_PTYS
 	  systems, it is safe to say N.
 
 config RAW_DRIVER
-        tristate "RAW driver (/dev/raw/rawN) (OBSOLETE)"
+        tristate "RAW driver (/dev/raw/rawN)"
+	depends on BLOCK
         help
           The raw driver permits block devices to be bound to /dev/raw/rawN.
           Once bound, I/O against /dev/raw/rawN uses efficient zero-copy I/O.
           See the raw(8) manpage for more details.
 
-          The raw driver is deprecated and will be removed soon.
-          Applications should simply open the device (eg /dev/hda1)
+          Applications should preferably open the device (eg /dev/hda1)
           with the O_DIRECT flag.
 
 config MAX_RAW_DEVS
diff --git a/arch/um/drivers/chan_user.c b/arch/um/drivers/chan_user.c
index 025764089ac..cfeb3f4a44a 100644
--- a/arch/um/drivers/chan_user.c
+++ b/arch/um/drivers/chan_user.c
@@ -11,6 +11,7 @@
 #include <termios.h>
 #include <sys/ioctl.h>
 #include "chan_user.h"
+#include "kern_constants.h"
 #include "os.h"
 #include "um_malloc.h"
 #include "user.h"
diff --git a/arch/um/drivers/cow_sys.h b/arch/um/drivers/cow_sys.h
index ca8c9e11a39..f5701fd2ef9 100644
--- a/arch/um/drivers/cow_sys.h
+++ b/arch/um/drivers/cow_sys.h
@@ -8,7 +8,7 @@
 
 static inline void *cow_malloc(int size)
 {
-	return kmalloc(size, UM_GFP_KERNEL);
+	return uml_kmalloc(size, UM_GFP_KERNEL);
 }
 
 static inline void cow_free(void *ptr)
diff --git a/arch/um/drivers/daemon_user.c b/arch/um/drivers/daemon_user.c
index f23c109a055..f8e85e0bdac 100644
--- a/arch/um/drivers/daemon_user.c
+++ b/arch/um/drivers/daemon_user.c
@@ -34,7 +34,7 @@ static struct sockaddr_un *new_addr(void *name, int len)
 {
 	struct sockaddr_un *sun;
 
-	sun = kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL);
+	sun = uml_kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL);
 	if (sun == NULL) {
 		printk(UM_KERN_ERR "new_addr: allocation of sockaddr_un "
 		       "failed\n");
@@ -83,7 +83,7 @@ static int connect_to_switch(struct daemon_data *pri)
 		goto out_close;
 	}
 
-	sun = kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL);
+	sun = uml_kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL);
 	if (sun == NULL) {
 		printk(UM_KERN_ERR "new_addr: allocation of sockaddr_un "
 		       "failed\n");
diff --git a/arch/um/drivers/fd.c b/arch/um/drivers/fd.c
index 0a2bb5b64b8..f5a981a1624 100644
--- a/arch/um/drivers/fd.c
+++ b/arch/um/drivers/fd.c
@@ -40,7 +40,7 @@ static void *fd_init(char *str, int device, const struct chan_opts *opts)
 		return NULL;
 	}
 
-	data = kmalloc(sizeof(*data), UM_GFP_KERNEL);
+	data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
 	if (data == NULL)
 		return NULL;
 
diff --git a/arch/um/drivers/hostaudio_kern.c b/arch/um/drivers/hostaudio_kern.c
index ff1b22b69e9..368219cc236 100644
--- a/arch/um/drivers/hostaudio_kern.c
+++ b/arch/um/drivers/hostaudio_kern.c
@@ -154,7 +154,7 @@ static int hostaudio_ioctl(struct inode *inode, struct file *file,
 	case SNDCTL_DSP_SUBDIVIDE:
 	case SNDCTL_DSP_SETFRAGMENT:
 		if (get_user(data, (int __user *) arg))
-			return EFAULT;
+			return -EFAULT;
 		break;
 	default:
 		break;
diff --git a/arch/um/drivers/mcast_user.c b/arch/um/drivers/mcast_user.c
index 5f647d7a729..ee19e91568a 100644
--- a/arch/um/drivers/mcast_user.c
+++ b/arch/um/drivers/mcast_user.c
@@ -15,6 +15,7 @@
 #include <unistd.h>
 #include <errno.h>
 #include <netinet/in.h>
+#include "kern_constants.h"
 #include "mcast.h"
 #include "net_user.h"
 #include "um_malloc.h"
@@ -24,7 +25,7 @@ static struct sockaddr_in *new_addr(char *addr, unsigned short port)
 {
 	struct sockaddr_in *sin;
 
-	sin = kmalloc(sizeof(struct sockaddr_in), UM_GFP_KERNEL);
+	sin = uml_kmalloc(sizeof(struct sockaddr_in), UM_GFP_KERNEL);
 	if (sin == NULL) {
 		printk(UM_KERN_ERR "new_addr: allocation of sockaddr_in "
 		       "failed\n");
diff --git a/arch/um/drivers/net_user.c b/arch/um/drivers/net_user.c
index abf2653f551..9415dd9e63e 100644
--- a/arch/um/drivers/net_user.c
+++ b/arch/um/drivers/net_user.c
@@ -222,7 +222,7 @@ static void change(char *dev, char *what, unsigned char *addr,
 		netmask[2], netmask[3]);
 
 	output_len = UM_KERN_PAGE_SIZE;
-	output = kmalloc(output_len, UM_GFP_KERNEL);
+	output = uml_kmalloc(output_len, UM_GFP_KERNEL);
 	if (output == NULL)
 		printk(UM_KERN_ERR "change : failed to allocate output "
 		       "buffer\n");
diff --git a/arch/um/drivers/pcap_user.c b/arch/um/drivers/pcap_user.c
index e9809356c53..5f903587d69 100644
--- a/arch/um/drivers/pcap_user.c
+++ b/arch/um/drivers/pcap_user.c
@@ -50,7 +50,7 @@ static int pcap_open(void *data)
 			return -EIO;
 		}
 
-		pri->compiled = kmalloc(sizeof(struct bpf_program),
+		pri->compiled = uml_kmalloc(sizeof(struct bpf_program),
 					UM_GFP_KERNEL);
 		if (pri->compiled == NULL) {
 			printk(UM_KERN_ERR "pcap_open : kmalloc failed\n");
diff --git a/arch/um/drivers/port_user.c b/arch/um/drivers/port_user.c
index d269ca387f1..b49bf56a56a 100644
--- a/arch/um/drivers/port_user.c
+++ b/arch/um/drivers/port_user.c
@@ -47,7 +47,7 @@ static void *port_init(char *str, int device, const struct chan_opts *opts)
 	if (kern_data == NULL)
 		return NULL;
 
-	data = kmalloc(sizeof(*data), UM_GFP_KERNEL);
+	data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
 	if (data == NULL)
 		goto err;
 
diff --git a/arch/um/drivers/pty.c b/arch/um/drivers/pty.c
index 49c79dda604..1113911dcb2 100644
--- a/arch/um/drivers/pty.c
+++ b/arch/um/drivers/pty.c
@@ -29,7 +29,7 @@ static void *pty_chan_init(char *str, int device, const struct chan_opts *opts)
 {
 	struct pty_chan *data;
 
-	data = kmalloc(sizeof(*data), UM_GFP_KERNEL);
+	data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
 	if (data == NULL)
 		return NULL;
 
diff --git a/arch/um/drivers/random.c b/arch/um/drivers/random.c
index 71f0959c153..4949044773b 100644
--- a/arch/um/drivers/random.c
+++ b/arch/um/drivers/random.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 2005 Jeff Dike <jdike@addtoit.com> */
+/* Copyright (C) 2005 - 2008 Jeff Dike <jdike@{linux.intel,addtoit}.com> */
+
 /* Much of this ripped from drivers/char/hw_random.c, see there for other
  * copyright.
  *
@@ -8,16 +9,18 @@
 #include <linux/sched.h>
 #include <linux/module.h>
 #include <linux/fs.h>
+#include <linux/interrupt.h>
 #include <linux/miscdevice.h>
 #include <linux/delay.h>
 #include <asm/uaccess.h>
+#include "irq_kern.h"
 #include "os.h"
 
 /*
  * core module and version information
  */
 #define RNG_VERSION "1.0.0"
-#define RNG_MODULE_NAME "random"
+#define RNG_MODULE_NAME "hw_random"
 
 #define RNG_MISCDEV_MINOR		183 /* official */
 
@@ -26,47 +29,67 @@
  * protects against a module being loaded twice at the same time.
  */
 static int random_fd = -1;
+static DECLARE_WAIT_QUEUE_HEAD(host_read_wait);
 
 static int rng_dev_open (struct inode *inode, struct file *filp)
 {
 	/* enforce read-only access to this chrdev */
 	if ((filp->f_mode & FMODE_READ) == 0)
 		return -EINVAL;
-	if (filp->f_mode & FMODE_WRITE)
+	if ((filp->f_mode & FMODE_WRITE) != 0)
 		return -EINVAL;
 
 	return 0;
 }
 
+static atomic_t host_sleep_count = ATOMIC_INIT(0);
+
 static ssize_t rng_dev_read (struct file *filp, char __user *buf, size_t size,
-                             loff_t * offp)
+			     loff_t *offp)
 {
-        u32 data;
-        int n, ret = 0, have_data;
-
-        while(size){
-                n = os_read_file(random_fd, &data, sizeof(data));
-                if(n > 0){
-                        have_data = n;
-                        while (have_data && size) {
-                                if (put_user((u8)data, buf++)) {
-                                        ret = ret ? : -EFAULT;
-                                        break;
-                                }
-                                size--;
-                                ret++;
-                                have_data--;
-                                data>>=8;
-                        }
-                }
-                else if(n == -EAGAIN){
-                        if (filp->f_flags & O_NONBLOCK)
-                                return ret ? : -EAGAIN;
-
-                        if(need_resched())
-                                schedule_timeout_interruptible(1);
-                }
-                else return n;
+	u32 data;
+	int n, ret = 0, have_data;
+
+	while (size) {
+		n = os_read_file(random_fd, &data, sizeof(data));
+		if (n > 0) {
+			have_data = n;
+			while (have_data && size) {
+				if (put_user((u8) data, buf++)) {
+					ret = ret ? : -EFAULT;
+					break;
+				}
+				size--;
+				ret++;
+				have_data--;
+				data >>= 8;
+			}
+		}
+		else if (n == -EAGAIN) {
+			DECLARE_WAITQUEUE(wait, current);
+
+			if (filp->f_flags & O_NONBLOCK)
+				return ret ? : -EAGAIN;
+
+			atomic_inc(&host_sleep_count);
+			reactivate_fd(random_fd, RANDOM_IRQ);
+			add_sigio_fd(random_fd);
+
+			add_wait_queue(&host_read_wait, &wait);
+			set_task_state(current, TASK_INTERRUPTIBLE);
+
+			schedule();
+			set_task_state(current, TASK_RUNNING);
+			remove_wait_queue(&host_read_wait, &wait);
+
+			if (atomic_dec_and_test(&host_sleep_count)) {
+				ignore_sigio_fd(random_fd);
+				deactivate_fd(random_fd, RANDOM_IRQ);
+			}
+		}
+		else
+			return n;
+
 		if (signal_pending (current))
 			return ret ? : -ERESTARTSYS;
 	}
@@ -86,6 +109,13 @@ static struct miscdevice rng_miscdev = {
 	&rng_chrdev_ops,
 };
 
+static irqreturn_t random_interrupt(int irq, void *data)
+{
+	wake_up(&host_read_wait);
+
+	return IRQ_HANDLED;
+}
+
 /*
  * rng_init - initialize RNG module
  */
@@ -93,28 +123,33 @@ static int __init rng_init (void)
 {
 	int err;
 
-        err = os_open_file("/dev/random", of_read(OPENFLAGS()), 0);
-        if(err < 0)
-                goto out;
+	err = os_open_file("/dev/random", of_read(OPENFLAGS()), 0);
+	if (err < 0)
+		goto out;
 
-        random_fd = err;
+	random_fd = err;
 
-        err = os_set_fd_block(random_fd, 0);
-        if(err)
+	err = um_request_irq(RANDOM_IRQ, random_fd, IRQ_READ, random_interrupt,
+			     IRQF_DISABLED | IRQF_SAMPLE_RANDOM, "random",
+			     NULL);
+	if (err)
 		goto err_out_cleanup_hw;
 
+	sigio_broken(random_fd, 1);
+
 	err = misc_register (&rng_miscdev);
 	if (err) {
-		printk (KERN_ERR RNG_MODULE_NAME ": misc device register failed\n");
+		printk (KERN_ERR RNG_MODULE_NAME ": misc device register "
+			"failed\n");
 		goto err_out_cleanup_hw;
 	}
+out:
+	return err;
 
- out:
-        return err;
-
- err_out_cleanup_hw:
-        random_fd = -1;
-        goto out;
+err_out_cleanup_hw:
+	os_close_file(random_fd);
+	random_fd = -1;
+	goto out;
 }
 
 /*
@@ -122,6 +157,7 @@ static int __init rng_init (void)
  */
 static void __exit rng_cleanup (void)
 {
+	os_close_file(random_fd);
 	misc_deregister (&rng_miscdev);
 }
 
diff --git a/arch/um/drivers/slip_user.c b/arch/um/drivers/slip_user.c
index 8b80505a3fb..a1c2d2c98a9 100644
--- a/arch/um/drivers/slip_user.c
+++ b/arch/um/drivers/slip_user.c
@@ -96,7 +96,7 @@ static int slip_tramp(char **argv, int fd)
 	pid = err;
 
 	output_len = UM_KERN_PAGE_SIZE;
-	output = kmalloc(output_len, UM_GFP_KERNEL);
+	output = uml_kmalloc(output_len, UM_GFP_KERNEL);
 	if (output == NULL) {
 		printk(UM_KERN_ERR "slip_tramp : failed to allocate output "
 		       "buffer\n");
diff --git a/arch/um/drivers/tty.c b/arch/um/drivers/tty.c
index c930fedc517..495858a090e 100644
--- a/arch/um/drivers/tty.c
+++ b/arch/um/drivers/tty.c
@@ -29,7 +29,7 @@ static void *tty_chan_init(char *str, int device, const struct chan_opts *opts)
 	}
 	str++;
 
-	data = kmalloc(sizeof(*data), UM_GFP_KERNEL);
+	data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
 	if (data == NULL)
 		return NULL;
 	*data = ((struct tty_chan) { .dev 	= str,
diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index 5e45e39a8a8..b58fb8941d8 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -49,7 +49,6 @@
 #include "irq_user.h"
 #include "irq_kern.h"
 #include "ubd_user.h"
-#include "kern_util.h"
 #include "os.h"
 #include "mem.h"
 #include "mem_kern.h"
@@ -1178,8 +1177,8 @@ static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask,
 	 * by one word.  Thanks to Lynn Kerby for the fix and James McMechan
 	 * for the original diagnosis.
 	 */
-	if(*cow_offset == ((bitmap_len + sizeof(unsigned long) - 1) /
-			   sizeof(unsigned long) - 1))
+	if (*cow_offset == (DIV_ROUND_UP(bitmap_len,
+					 sizeof(unsigned long)) - 1))
 		(*cow_offset)--;
 
 	bitmap_words[0] = bitmap[*cow_offset];
diff --git a/arch/um/drivers/xterm.c b/arch/um/drivers/xterm.c
index 8a1c18a9b24..da2caa5a21e 100644
--- a/arch/um/drivers/xterm.c
+++ b/arch/um/drivers/xterm.c
@@ -30,7 +30,7 @@ static void *xterm_init(char *str, int device, const struct chan_opts *opts)
 {
 	struct xterm_chan *data;
 
-	data = kmalloc(sizeof(*data), UM_GFP_KERNEL);
+	data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
 	if (data == NULL)
 		return NULL;
 	*data = ((struct xterm_chan) { .pid 		= -1,
diff --git a/arch/um/include/as-layout.h b/arch/um/include/as-layout.h
index cac542d8ff7..58e852dfb0c 100644
--- a/arch/um/include/as-layout.h
+++ b/arch/um/include/as-layout.h
@@ -23,16 +23,16 @@
  */
 
 #ifdef __ASSEMBLY__
-#define _AC(X, Y)	(Y)
+#define _UML_AC(X, Y)	(Y)
 #else
-#define __AC(X, Y)	(X (Y))
-#define _AC(X, Y)	__AC(X, Y)
+#define __UML_AC(X, Y)	(X(Y))
+#define _UML_AC(X, Y)	__UML_AC(X, Y)
 #endif
 
-#define STUB_START _AC(, 0x100000)
-#define STUB_CODE _AC((unsigned long), STUB_START)
-#define STUB_DATA _AC((unsigned long), STUB_CODE + UM_KERN_PAGE_SIZE)
-#define STUB_END _AC((unsigned long), STUB_DATA + UM_KERN_PAGE_SIZE)
+#define STUB_START _UML_AC(, 0x100000)
+#define STUB_CODE _UML_AC((unsigned long), STUB_START)
+#define STUB_DATA _UML_AC((unsigned long), STUB_CODE + UM_KERN_PAGE_SIZE)
+#define STUB_END _UML_AC((unsigned long), STUB_DATA + UM_KERN_PAGE_SIZE)
 
 #ifndef __ASSEMBLY__
 
diff --git a/arch/um/include/line.h b/arch/um/include/line.h
index 979b73e6352..311a0d3d93a 100644
--- a/arch/um/include/line.h
+++ b/arch/um/include/line.h
@@ -58,11 +58,11 @@ struct line {
 };
 
 #define LINE_INIT(str, d) \
-	{ .count_lock =	SPIN_LOCK_UNLOCKED, \
+	{ .count_lock =	__SPIN_LOCK_UNLOCKED((str).count_lock), \
 	  .init_str =	str,	\
 	  .init_pri =	INIT_STATIC, \
 	  .valid =	1, \
-	  .lock =	SPIN_LOCK_UNLOCKED, \
+	  .lock =	__SPIN_LOCK_UNLOCKED((str).lock), \
 	  .driver =	d }
 
 extern void line_close(struct tty_struct *tty, struct file * filp);
diff --git a/arch/um/include/os.h b/arch/um/include/os.h
index 32c799e3a49..db5be46e3e1 100644
--- a/arch/um/include/os.h
+++ b/arch/um/include/os.h
@@ -290,6 +290,7 @@ extern void os_set_ioignore(void);
 extern int add_sigio_fd(int fd);
 extern int ignore_sigio_fd(int fd);
 extern void maybe_sigio_broken(int fd, int read);
+extern void sigio_broken(int fd, int read);
 
 /* sys-x86_64/prctl.c */
 extern int os_arch_prctl(int pid, int code, unsigned long *addr);
@@ -298,6 +299,6 @@ extern int os_arch_prctl(int pid, int code, unsigned long *addr);
 extern int get_pty(void);
 
 /* sys-$ARCH/task_size.c */
-extern unsigned long os_get_task_size(void);
+extern unsigned long os_get_top_address(void);
 
 #endif
diff --git a/arch/um/include/process.h b/arch/um/include/process.h
index 5af9157ff54..bb873a51262 100644
--- a/arch/um/include/process.h
+++ b/arch/um/include/process.h
@@ -1,5 +1,5 @@
 /* 
- * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Copyright (C) 2000 - 2008 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  * Licensed under the GPL
  */
 
@@ -8,18 +8,10 @@
 
 #include <signal.h>
 
-extern void sig_handler(int sig, struct sigcontext sc);
-extern void alarm_handler(int sig, struct sigcontext sc);
+/* Copied from linux/compiler-gcc.h since we can't include it directly */
+#define barrier() __asm__ __volatile__("": : :"memory")
 
-#endif
+extern void sig_handler(int sig, struct sigcontext *sc);
+extern void alarm_handler(int sig, struct sigcontext *sc);
 
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
+#endif
diff --git a/arch/um/include/skas_ptrace.h b/arch/um/include/skas_ptrace.h
index cd2327d09c8..3d31bbacd01 100644
--- a/arch/um/include/skas_ptrace.h
+++ b/arch/um/include/skas_ptrace.h
@@ -1,5 +1,5 @@
 /* 
- * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  * Licensed under the GPL
  */
 
@@ -12,14 +12,3 @@
 #include "sysdep/skas_ptrace.h"
 
 #endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/include/sysdep-i386/ptrace_user.h b/arch/um/include/sysdep-i386/ptrace_user.h
index 75650723c38..ef56247e414 100644
--- a/arch/um/include/sysdep-i386/ptrace_user.h
+++ b/arch/um/include/sysdep-i386/ptrace_user.h
@@ -41,38 +41,10 @@
 #define PT_SP_OFFSET PT_OFFSET(UESP)
 #define PT_SP(regs) ((regs)[UESP])
 
-#define FP_SIZE ((HOST_XFP_SIZE > HOST_FP_SIZE) ? HOST_XFP_SIZE : HOST_FP_SIZE)
+#define FP_SIZE ((HOST_FPX_SIZE > HOST_FP_SIZE) ? HOST_FPX_SIZE : HOST_FP_SIZE)
 
 #ifndef FRAME_SIZE
 #define FRAME_SIZE (17)
 #endif
-#define FRAME_SIZE_OFFSET (FRAME_SIZE * sizeof(unsigned long))
-
-#define FP_FRAME_SIZE (27)
-#define FPX_FRAME_SIZE (128)
-
-#ifdef PTRACE_GETREGS
-#define UM_HAVE_GETREGS
-#endif
-
-#ifdef PTRACE_SETREGS
-#define UM_HAVE_SETREGS
-#endif
-
-#ifdef PTRACE_GETFPREGS
-#define UM_HAVE_GETFPREGS
-#endif
-
-#ifdef PTRACE_SETFPREGS
-#define UM_HAVE_SETFPREGS
-#endif
-
-#ifdef PTRACE_GETFPXREGS
-#define UM_HAVE_GETFPXREGS
-#endif
-
-#ifdef PTRACE_SETFPXREGS
-#define UM_HAVE_SETFPXREGS
-#endif
 
 #endif
diff --git a/arch/um/include/sysdep-i386/sigcontext.h b/arch/um/include/sysdep-i386/sigcontext.h
index 67e77122aa4..f583c87111a 100644
--- a/arch/um/include/sysdep-i386/sigcontext.h
+++ b/arch/um/include/sysdep-i386/sigcontext.h
@@ -10,7 +10,7 @@
 
 #define IP_RESTART_SYSCALL(ip) ((ip) -= 2)
 
-#define GET_FAULTINFO_FROM_SC(fi,sc) \
+#define GET_FAULTINFO_FROM_SC(fi, sc) \
 	{ \
 		(fi).cr2 = SC_CR2(sc); \
 		(fi).error_code = SC_ERR(sc); \
diff --git a/arch/um/include/sysdep-x86_64/ptrace_user.h b/arch/um/include/sysdep-x86_64/ptrace_user.h
index 45c0bd881cb..4dbccdb58f4 100644
--- a/arch/um/include/sysdep-x86_64/ptrace_user.h
+++ b/arch/um/include/sysdep-x86_64/ptrace_user.h
@@ -48,7 +48,8 @@
 #define PT_ORIG_RAX_OFFSET (ORIG_RAX)
 #define PT_ORIG_RAX(regs) ((regs)[PT_INDEX(ORIG_RAX)])
 
-/* x86_64 FC3 doesn't define this in /usr/include/linux/ptrace.h even though
+/*
+ * x86_64 FC3 doesn't define this in /usr/include/linux/ptrace.h even though
  * it's defined in the kernel's include/linux/ptrace.h. Additionally, use the
  * 2.4 name and value for 2.4 host compatibility.
  */
@@ -56,7 +57,8 @@
 #define PTRACE_OLDSETOPTIONS 21
 #endif
 
-/* These are before the system call, so the system call number is RAX
+/*
+ * These are before the system call, so the system call number is RAX
  * rather than ORIG_RAX, and arg4 is R10 rather than RCX
  */
 #define REGS_SYSCALL_NR PT_INDEX(RAX)
@@ -73,14 +75,3 @@
 #define FP_SIZE (HOST_FP_SIZE)
 
 #endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/include/um_malloc.h b/arch/um/include/um_malloc.h
index 0ad17cb83d9..c554d706d10 100644
--- a/arch/um/include/um_malloc.h
+++ b/arch/um/include/um_malloc.h
@@ -8,15 +8,12 @@
 
 #include "kern_constants.h"
 
-extern void *__kmalloc(int size, int flags);
-static inline void *kmalloc(int size, int flags)
-{
-	return __kmalloc(size, flags);
-}
-
+extern void *uml_kmalloc(int size, int flags);
 extern void kfree(const void *ptr);
 
 extern void *vmalloc(unsigned long size);
 extern void vfree(void *ptr);
 
 #endif /* __UM_MALLOC_H__ */
+
+
diff --git a/arch/um/kernel/dyn.lds.S b/arch/um/kernel/dyn.lds.S
index 26090b7f323..9975e1ab44f 100644
--- a/arch/um/kernel/dyn.lds.S
+++ b/arch/um/kernel/dyn.lds.S
@@ -1,4 +1,5 @@
 #include <asm-generic/vmlinux.lds.h>
+#include <asm/page.h>
 
 OUTPUT_FORMAT(ELF_FORMAT)
 OUTPUT_ARCH(ELF_ARCH)
@@ -21,7 +22,7 @@ SECTIONS
 	_einittext = .;
   }
 
-  . = ALIGN(4096);
+  . = ALIGN(PAGE_SIZE);
 
   /* Read-only sections, merged into text segment: */
   .hash           : { *(.hash) }
@@ -68,9 +69,9 @@ SECTIONS
     /* .gnu.warning sections are handled specially by elf32.em.  */
     *(.gnu.warning)
 
-    . = ALIGN(4096);
+    . = ALIGN(PAGE_SIZE);
   } =0x90909090
-  . = ALIGN(4096);
+  . = ALIGN(PAGE_SIZE);
   .syscall_stub : {
 	__syscall_stub_start = .;
 	*(.__syscall_stub*)
diff --git a/arch/um/kernel/init_task.c b/arch/um/kernel/init_task.c
index dcfceca9505..910eda8fca1 100644
--- a/arch/um/kernel/init_task.c
+++ b/arch/um/kernel/init_task.c
@@ -12,7 +12,6 @@
 
 static struct fs_struct init_fs = INIT_FS;
 struct mm_struct init_mm = INIT_MM(init_mm);
-static struct files_struct init_files = INIT_FILES;
 static struct signal_struct init_signals = INIT_SIGNALS(init_signals);
 static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand);
 EXPORT_SYMBOL(init_mm);
diff --git a/arch/um/kernel/ksyms.c b/arch/um/kernel/ksyms.c
index 66e2a305a8d..ccc02a616c2 100644
--- a/arch/um/kernel/ksyms.c
+++ b/arch/um/kernel/ksyms.c
@@ -60,6 +60,11 @@ EXPORT_SYMBOL(os_rcv_fd);
 EXPORT_SYMBOL(run_helper);
 EXPORT_SYMBOL(start_thread);
 
+EXPORT_SYMBOL(add_sigio_fd);
+EXPORT_SYMBOL(ignore_sigio_fd);
+EXPORT_SYMBOL(deactivate_fd);
+EXPORT_SYMBOL(sigio_broken);
+
 #ifdef CONFIG_SMP
 
 /* required for SMP */
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index 2eea1ff235e..b0ee64622ff 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -375,3 +375,8 @@ pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
 	return pmd;
 }
 #endif
+
+void *uml_kmalloc(int size, int flags)
+{
+	return kmalloc(size, flags);
+}
diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
index 0d0cea2ac98..c3e2f369c33 100644
--- a/arch/um/kernel/time.c
+++ b/arch/um/kernel/time.c
@@ -75,7 +75,7 @@ static irqreturn_t um_timer(int irq, void *dev)
 
 static cycle_t itimer_read(void)
 {
-	return os_nsecs();
+	return os_nsecs() / 1000;
 }
 
 static struct clocksource itimer_clocksource = {
@@ -83,7 +83,7 @@ static struct clocksource itimer_clocksource = {
 	.rating		= 300,
 	.read		= itimer_read,
 	.mask		= CLOCKSOURCE_MASK(64),
-	.mult		= 1,
+	.mult		= 1000,
 	.shift		= 0,
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
 };
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index 56deed62344..8d84250324b 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -150,7 +150,7 @@ __uml_setup("root=", uml_root_setup,
 static int __init no_skas_debug_setup(char *line, int *add)
 {
 	printf("'debug' is not necessary to gdb UML in skas mode - run \n");
-	printf("'gdb linux'");
+	printf("'gdb linux'\n");
 
 	return 0;
 }
@@ -258,6 +258,7 @@ int __init linux_main(int argc, char **argv)
 {
 	unsigned long avail, diff;
 	unsigned long virtmem_size, max_physmem;
+	unsigned long stack;
 	unsigned int i;
 	int add;
 	char * mode;
@@ -273,7 +274,7 @@ int __init linux_main(int argc, char **argv)
 	if (have_root == 0)
 		add_arg(DEFAULT_COMMAND_LINE);
 
-	host_task_size = os_get_task_size();
+	host_task_size = os_get_top_address();
 	/*
 	 * TASK_SIZE needs to be PGDIR_SIZE aligned or else exit_mmap craps
 	 * out
@@ -348,7 +349,9 @@ int __init linux_main(int argc, char **argv)
 	}
 
 	virtmem_size = physmem_size;
-	avail = TASK_SIZE - start_vm;
+	stack = (unsigned long) argv;
+	stack &= ~(1024 * 1024 - 1);
+	avail = stack - start_vm;
 	if (physmem_size > avail)
 		virtmem_size = avail;
 	end_vm = start_vm + virtmem_size;
diff --git a/arch/um/kernel/uml.lds.S b/arch/um/kernel/uml.lds.S
index 5828c1d5450..11b835248b8 100644
--- a/arch/um/kernel/uml.lds.S
+++ b/arch/um/kernel/uml.lds.S
@@ -1,4 +1,5 @@
 #include <asm-generic/vmlinux.lds.h>
+#include <asm/page.h>
 
 OUTPUT_FORMAT(ELF_FORMAT)
 OUTPUT_ARCH(ELF_ARCH)
@@ -26,7 +27,7 @@ SECTIONS
 	INIT_TEXT
 	_einittext = .;
   }
-  . = ALIGN(4096);
+  . = ALIGN(PAGE_SIZE);
 
   .text      :
   {
@@ -39,7 +40,7 @@ SECTIONS
     *(.gnu.linkonce.t*)
   }
 
-  . = ALIGN(4096);
+  . = ALIGN(PAGE_SIZE);
   .syscall_stub : {
 	__syscall_stub_start = .;
 	*(.__syscall_stub*)
@@ -79,7 +80,7 @@ SECTIONS
   .sdata     : { *(.sdata) }
   _edata  =  .;
   PROVIDE (edata = .);
-  . = ALIGN(0x1000);
+  . = ALIGN(PAGE_SIZE);
   .sbss      :
   {
    __bss_start = .;
diff --git a/arch/um/os-Linux/drivers/ethertap_user.c b/arch/um/os-Linux/drivers/ethertap_user.c
index 6fb0b174f53..cc72cb2c1af 100644
--- a/arch/um/os-Linux/drivers/ethertap_user.c
+++ b/arch/um/os-Linux/drivers/ethertap_user.c
@@ -52,7 +52,7 @@ static void etap_change(int op, unsigned char *addr, unsigned char *netmask,
 		return;
 	}
 
-	output = kmalloc(UM_KERN_PAGE_SIZE, UM_GFP_KERNEL);
+	output = uml_kmalloc(UM_KERN_PAGE_SIZE, UM_GFP_KERNEL);
 	if (output == NULL)
 		printk(UM_KERN_ERR "etap_change : Failed to allocate output "
 		       "buffer\n");
@@ -165,7 +165,7 @@ static int etap_open(void *data)
 	err = etap_tramp(pri->dev_name, pri->gate_addr, control_fds[0],
 			 control_fds[1], data_fds[0], data_fds[1]);
 	output_len = UM_KERN_PAGE_SIZE;
-	output = kmalloc(output_len, UM_GFP_KERNEL);
+	output = uml_kmalloc(output_len, UM_GFP_KERNEL);
 	read_output(control_fds[0], output, output_len);
 
 	if (output == NULL)
diff --git a/arch/um/os-Linux/helper.c b/arch/um/os-Linux/helper.c
index f25c29a12d0..30860b89ec5 100644
--- a/arch/um/os-Linux/helper.c
+++ b/arch/um/os-Linux/helper.c
@@ -7,6 +7,7 @@
 #include <unistd.h>
 #include <errno.h>
 #include <sched.h>
+#include <linux/limits.h>
 #include <sys/socket.h>
 #include <sys/wait.h>
 #include "kern_constants.h"
@@ -71,8 +72,8 @@ int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv)
 	data.pre_data = pre_data;
 	data.argv = argv;
 	data.fd = fds[1];
-	data.buf = __cant_sleep() ? kmalloc(PATH_MAX, UM_GFP_ATOMIC) :
-					kmalloc(PATH_MAX, UM_GFP_KERNEL);
+	data.buf = __cant_sleep() ? uml_kmalloc(PATH_MAX, UM_GFP_ATOMIC) :
+					uml_kmalloc(PATH_MAX, UM_GFP_KERNEL);
 	pid = clone(helper_child, (void *) sp, CLONE_VM, &data);
 	if (pid < 0) {
 		ret = -errno;
diff --git a/arch/um/os-Linux/main.c b/arch/um/os-Linux/main.c
index abb9b0ffd96..eee69b9f52c 100644
--- a/arch/um/os-Linux/main.c
+++ b/arch/um/os-Linux/main.c
@@ -199,7 +199,7 @@ void *__wrap_malloc(int size)
 		return __real_malloc(size);
 	else if (size <= UM_KERN_PAGE_SIZE)
 		/* finding contiguous pages can be hard*/
-		ret = kmalloc(size, UM_GFP_KERNEL);
+		ret = uml_kmalloc(size, UM_GFP_KERNEL);
 	else ret = vmalloc(size);
 
 	/*
diff --git a/arch/um/os-Linux/sigio.c b/arch/um/os-Linux/sigio.c
index abf47a7c4ab..eb8f2e4be19 100644
--- a/arch/um/os-Linux/sigio.c
+++ b/arch/um/os-Linux/sigio.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Copyright (C) 2002 - 2008 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  * Licensed under the GPL
  */
 
@@ -15,6 +15,7 @@
 #include "kern_util.h"
 #include "init.h"
 #include "os.h"
+#include "process.h"
 #include "sigio.h"
 #include "um_malloc.h"
 #include "user.h"
@@ -109,7 +110,7 @@ static int need_poll(struct pollfds *polls, int n)
 	if (n <= polls->size)
 		return 0;
 
-	new = kmalloc(n * sizeof(struct pollfd), UM_GFP_ATOMIC);
+	new = uml_kmalloc(n * sizeof(struct pollfd), UM_GFP_ATOMIC);
 	if (new == NULL) {
 		printk(UM_KERN_ERR "need_poll : failed to allocate new "
 		       "pollfds\n");
@@ -243,7 +244,7 @@ static struct pollfd *setup_initial_poll(int fd)
 {
 	struct pollfd *p;
 
-	p = kmalloc(sizeof(struct pollfd), UM_GFP_KERNEL);
+	p = uml_kmalloc(sizeof(struct pollfd), UM_GFP_KERNEL);
 	if (p == NULL) {
 		printk(UM_KERN_ERR "setup_initial_poll : failed to allocate "
 		       "poll\n");
@@ -338,20 +339,10 @@ out_close1:
 	close(l_write_sigio_fds[1]);
 }
 
-/* Changed during early boot */
-static int pty_output_sigio = 0;
-static int pty_close_sigio = 0;
-
-void maybe_sigio_broken(int fd, int read)
+void sigio_broken(int fd, int read)
 {
 	int err;
 
-	if (!isatty(fd))
-		return;
-
-	if ((read || pty_output_sigio) && (!read || pty_close_sigio))
-		return;
-
 	write_sigio_workaround();
 
 	sigio_lock();
@@ -370,6 +361,21 @@ out:
 	sigio_unlock();
 }
 
+/* Changed during early boot */
+static int pty_output_sigio;
+static int pty_close_sigio;
+
+void maybe_sigio_broken(int fd, int read)
+{
+	if (!isatty(fd))
+		return;
+
+	if ((read || pty_output_sigio) && (!read || pty_close_sigio))
+		return;
+
+	sigio_broken(fd, read);
+}
+
 static void sigio_cleanup(void)
 {
 	if (write_sigio_pid == -1)
@@ -383,7 +389,7 @@ static void sigio_cleanup(void)
 __uml_exitcall(sigio_cleanup);
 
 /* Used as a flag during SIGIO testing early in boot */
-static volatile int got_sigio = 0;
+static int got_sigio;
 
 static void __init handler(int sig)
 {
@@ -498,7 +504,8 @@ static void tty_output(int master, int slave)
 	if (errno != EAGAIN)
 		printk(UM_KERN_ERR "tty_output : write failed, errno = %d\n",
 		       errno);
-	while (((n = read(slave, buf, sizeof(buf))) > 0) && !got_sigio)
+	while (((n = read(slave, buf, sizeof(buf))) > 0) &&
+	       !({ barrier(); got_sigio; }))
 		;
 
 	if (got_sigio) {
diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c
index 3f1694b134c..5aade6027e4 100644
--- a/arch/um/os-Linux/signal.c
+++ b/arch/um/os-Linux/signal.c
@@ -12,6 +12,7 @@
 #include "as-layout.h"
 #include "kern_util.h"
 #include "os.h"
+#include "process.h"
 #include "sysdep/barrier.h"
 #include "sysdep/sigcontext.h"
 #include "user.h"
diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index 1e8cba6550a..172ad8f72e1 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -55,7 +55,7 @@ static int ptrace_dump_regs(int pid)
  * Signals that are OK to receive in the stub - we'll just continue it.
  * SIGWINCH will happen when UML is inside a detached screen.
  */
-#define STUB_SIG_MASK (1 << SIGVTALRM)
+#define STUB_SIG_MASK ((1 << SIGVTALRM) | (1 << SIGWINCH))
 
 /* Signals that the stub will finish with - anything else is an error */
 #define STUB_DONE_MASK (1 << SIGTRAP)
@@ -442,7 +442,7 @@ void userspace(struct uml_pt_regs *regs)
 				unblock_signals();
 				break;
 			default:
-			        printk(UM_KERN_ERR "userspace - child stopped "
+				printk(UM_KERN_ERR "userspace - child stopped "
 				       "with signal %d\n", sig);
 				fatal_sigsegv();
 			}
diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c
index 997d01944f9..183db26d01b 100644
--- a/arch/um/os-Linux/start_up.c
+++ b/arch/um/os-Linux/start_up.c
@@ -23,6 +23,7 @@
 #include "mem_user.h"
 #include "ptrace_user.h"
 #include "registers.h"
+#include "skas.h"
 #include "skas_ptrace.h"
 
 static void ptrace_child(void)
@@ -120,8 +121,10 @@ static int stop_ptraced_child(int pid, int exitcode, int mustexit)
 {
 	int status, n, ret = 0;
 
-	if (ptrace(PTRACE_CONT, pid, 0, 0) < 0)
-		fatal_perror("stop_ptraced_child : ptrace failed");
+	if (ptrace(PTRACE_CONT, pid, 0, 0) < 0) {
+		perror("stop_ptraced_child : ptrace failed");
+		return -1;
+	}
 	CATCH_EINTR(n = waitpid(pid, &status, 0));
 	if (!WIFEXITED(status) || (WEXITSTATUS(status) != exitcode)) {
 		int exit_with = WEXITSTATUS(status);
@@ -140,14 +143,27 @@ static int stop_ptraced_child(int pid, int exitcode, int mustexit)
 }
 
 /* Changed only during early boot */
-int ptrace_faultinfo = 1;
-int ptrace_ldt = 1;
-int proc_mm = 1;
-int skas_needs_stub = 0;
+int ptrace_faultinfo;
+static int disable_ptrace_faultinfo;
+
+int ptrace_ldt;
+static int disable_ptrace_ldt;
+
+int proc_mm;
+static int disable_proc_mm;
+
+int have_switch_mm;
+static int disable_switch_mm;
+
+int skas_needs_stub;
 
 static int __init skas0_cmd_param(char *str, int* add)
 {
-	ptrace_faultinfo = proc_mm = 0;
+	disable_ptrace_faultinfo = 1;
+	disable_ptrace_ldt = 1;
+	disable_proc_mm = 1;
+	disable_switch_mm = 1;
+
 	return 0;
 }
 
@@ -157,15 +173,12 @@ static int __init mode_skas0_cmd_param(char *str, int* add)
 	__attribute__((alias("skas0_cmd_param")));
 
 __uml_setup("skas0", skas0_cmd_param,
-		"skas0\n"
-		"    Disables SKAS3 usage, so that SKAS0 is used, unless \n"
-	        "    you specify mode=tt.\n\n");
+"skas0\n"
+"    Disables SKAS3 and SKAS4 usage, so that SKAS0 is used\n\n");
 
 __uml_setup("mode=skas0", mode_skas0_cmd_param,
-		"mode=skas0\n"
-		"    Disables SKAS3 usage, so that SKAS0 is used, unless you \n"
-		"    specify mode=tt. Note that this was recently added - on \n"
-		"    older kernels you must use simply \"skas0\".\n\n");
+"mode=skas0\n"
+"    Disables SKAS3 and SKAS4 usage, so that SKAS0 is used.\n\n");
 
 /* Changed only during early boot */
 static int force_sysemu_disabled = 0;
@@ -201,7 +214,7 @@ static void __init check_sysemu(void)
 	if (n < 0)
 		fatal_perror("check_sysemu : wait failed");
 	if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
-		fatal("check_sysemu : expected SIGTRAP, got status = %d",
+		fatal("check_sysemu : expected SIGTRAP, got status = %d\n",
 		      status);
 
 	if (ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
@@ -243,9 +256,11 @@ static void __init check_sysemu(void)
 
 		if (WIFSTOPPED(status) &&
 		    (WSTOPSIG(status) == (SIGTRAP|0x80))) {
-			if (!count)
-				fatal("check_ptrace : SYSEMU_SINGLESTEP "
-				      "doesn't singlestep");
+			if (!count) {
+				non_fatal("check_ptrace : SYSEMU_SINGLESTEP "
+					  "doesn't singlestep");
+				goto fail;
+			}
 			n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_RET_OFFSET,
 				   os_getpid());
 			if (n < 0)
@@ -255,9 +270,12 @@ static void __init check_sysemu(void)
 		}
 		else if (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGTRAP))
 			count++;
-		else
-			fatal("check_ptrace : expected SIGTRAP or "
-			      "(SIGTRAP | 0x80), got status = %d", status);
+		else {
+			non_fatal("check_ptrace : expected SIGTRAP or "
+				  "(SIGTRAP | 0x80), got status = %d\n",
+				  status);
+			goto fail;
+		}
 	}
 	if (stop_ptraced_child(pid, 0, 0) < 0)
 		goto fail_stopped;
@@ -360,7 +378,7 @@ void __init os_early_checks(void)
 
 static int __init noprocmm_cmd_param(char *str, int* add)
 {
-	proc_mm = 0;
+	disable_proc_mm = 1;
 	return 0;
 }
 
@@ -372,7 +390,7 @@ __uml_setup("noprocmm", noprocmm_cmd_param,
 
 static int __init noptracefaultinfo_cmd_param(char *str, int* add)
 {
-	ptrace_faultinfo = 0;
+	disable_ptrace_faultinfo = 1;
 	return 0;
 }
 
@@ -384,7 +402,7 @@ __uml_setup("noptracefaultinfo", noptracefaultinfo_cmd_param,
 
 static int __init noptraceldt_cmd_param(char *str, int* add)
 {
-	ptrace_ldt = 0;
+	disable_ptrace_ldt = 1;
 	return 0;
 }
 
@@ -404,17 +422,15 @@ static inline void check_skas3_ptrace_faultinfo(void)
 
 	n = ptrace(PTRACE_FAULTINFO, pid, 0, &fi);
 	if (n < 0) {
-		ptrace_faultinfo = 0;
 		if (errno == EIO)
 			non_fatal("not found\n");
 		else
 			perror("not found");
-	}
+	} else if (disable_ptrace_faultinfo)
+		non_fatal("found but disabled on command line\n");
 	else {
-		if (!ptrace_faultinfo)
-			non_fatal("found but disabled on command line\n");
-		else
-			non_fatal("found\n");
+		ptrace_faultinfo = 1;
+		non_fatal("found\n");
 	}
 
 	stop_ptraced_child(pid, 1, 1);
@@ -437,38 +453,30 @@ static inline void check_skas3_ptrace_ldt(void)
 	if (n < 0) {
 		if (errno == EIO)
 			non_fatal("not found\n");
-		else {
+		else
 			perror("not found");
-		}
-		ptrace_ldt = 0;
-	}
+	} else if (disable_ptrace_ldt)
+		non_fatal("found, but use is disabled\n");
 	else {
-		if (ptrace_ldt)
-			non_fatal("found\n");
-		else
-			non_fatal("found, but use is disabled\n");
+		ptrace_ldt = 1;
+		non_fatal("found\n");
 	}
 
 	stop_ptraced_child(pid, 1, 1);
-#else
-	/* PTRACE_LDT might be disabled via cmdline option.
-	 * We want to override this, else we might use the stub
-	 * without real need
-	 */
-	ptrace_ldt = 1;
 #endif
 }
 
 static inline void check_skas3_proc_mm(void)
 {
 	non_fatal("  - /proc/mm...");
-	if (access("/proc/mm", W_OK) < 0) {
-		proc_mm = 0;
+	if (access("/proc/mm", W_OK) < 0)
 		perror("not found");
-	}
-	else if (!proc_mm)
+	else if (disable_proc_mm)
 		non_fatal("found but disabled on command line\n");
-	else non_fatal("found\n");
+	else {
+		proc_mm = 1;
+		non_fatal("found\n");
+	}
 }
 
 void can_do_skas(void)
diff --git a/arch/um/os-Linux/sys-i386/registers.c b/arch/um/os-Linux/sys-i386/registers.c
index b613473b3ec..229f7a53d8d 100644
--- a/arch/um/os-Linux/sys-i386/registers.c
+++ b/arch/um/os-Linux/sys-i386/registers.c
@@ -5,6 +5,8 @@
  */
 
 #include <errno.h>
+#include <sys/ptrace.h>
+#include <sys/user.h>
 #include "kern_constants.h"
 #include "longjmp.h"
 #include "user.h"
@@ -74,10 +76,10 @@ int put_fp_registers(int pid, unsigned long *regs)
 
 void arch_init_registers(int pid)
 {
-	unsigned long fpx_regs[HOST_XFP_SIZE];
+	struct user_fpxregs_struct fpx_regs;
 	int err;
 
-	err = ptrace(PTRACE_GETFPXREGS, pid, 0, fpx_regs);
+	err = ptrace(PTRACE_GETFPXREGS, pid, 0, &fpx_regs);
 	if (!err)
 		return;
 
diff --git a/arch/um/os-Linux/sys-i386/task_size.c b/arch/um/os-Linux/sys-i386/task_size.c
index ccb49b0aff5..be04c1e183b 100644
--- a/arch/um/os-Linux/sys-i386/task_size.c
+++ b/arch/um/os-Linux/sys-i386/task_size.c
@@ -63,7 +63,7 @@ static int page_ok(unsigned long page)
 	return ok;
 }
 
-unsigned long os_get_task_size(void)
+unsigned long os_get_top_address(void)
 {
 	struct sigaction sa, old;
 	unsigned long bottom = 0;
@@ -76,9 +76,9 @@ unsigned long os_get_task_size(void)
 	 * hosts, but shouldn't hurt otherwise.
 	 */
 	unsigned long top = 0xffffd000 >> UM_KERN_PAGE_SHIFT;
-	unsigned long test;
+	unsigned long test, original;
 
-	printf("Locating the top of the address space ... ");
+	printf("Locating the bottom of the address space ... ");
 	fflush(stdout);
 
 	/*
@@ -89,16 +89,31 @@ unsigned long os_get_task_size(void)
 	sigemptyset(&sa.sa_mask);
 	sa.sa_flags = SA_NODEFER;
 	if (sigaction(SIGSEGV, &sa, &old)) {
-		perror("os_get_task_size");
+		perror("os_get_top_address");
 		exit(1);
 	}
 
-	if (!page_ok(bottom)) {
-		fprintf(stderr, "Address 0x%x no good?\n",
-			bottom << UM_KERN_PAGE_SHIFT);
+	/* Manually scan the address space, bottom-up, until we find
+	 * the first valid page (or run out of them).
+	 */
+	for (bottom = 0; bottom < top; bottom++) {
+		if (page_ok(bottom))
+			break;
+	}
+
+	/* If we've got this far, we ran out of pages. */
+	if (bottom == top) {
+		fprintf(stderr, "Unable to determine bottom of address "
+			"space.\n");
 		exit(1);
 	}
 
+	printf("0x%x\n", bottom << UM_KERN_PAGE_SHIFT);
+	printf("Locating the top of the address space ... ");
+	fflush(stdout);
+
+	original = bottom;
+
 	/* This could happen with a 4G/4G split */
 	if (page_ok(top))
 		goto out;
@@ -114,7 +129,7 @@ unsigned long os_get_task_size(void)
 out:
 	/* Restore the old SIGSEGV handling */
 	if (sigaction(SIGSEGV, &old, NULL)) {
-		perror("os_get_task_size");
+		perror("os_get_top_address");
 		exit(1);
 	}
 	top <<= UM_KERN_PAGE_SHIFT;
diff --git a/arch/um/os-Linux/sys-x86_64/task_size.c b/arch/um/os-Linux/sys-x86_64/task_size.c
index fad6f57f8ee..26a0dd1f349 100644
--- a/arch/um/os-Linux/sys-x86_64/task_size.c
+++ b/arch/um/os-Linux/sys-x86_64/task_size.c
@@ -1,4 +1,4 @@
-unsigned long os_get_task_size(unsigned long shift)
+unsigned long os_get_top_address(unsigned long shift)
 {
 	/* The old value of CONFIG_TOP_ADDR */
 	return 0x7fc0000000;
diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c
index e4928059946..dec5678fc17 100644
--- a/arch/um/os-Linux/time.c
+++ b/arch/um/os-Linux/time.c
@@ -9,7 +9,9 @@
 #include <time.h>
 #include <sys/time.h>
 #include "kern_constants.h"
+#include "kern_util.h"
 #include "os.h"
+#include "process.h"
 #include "user.h"
 
 int set_interval(void)
@@ -58,12 +60,17 @@ static inline long long timeval_to_ns(const struct timeval *tv)
 long long disable_timer(void)
 {
 	struct itimerval time = ((struct itimerval) { { 0, 0 }, { 0, 0 } });
+	int remain, max = UM_NSEC_PER_SEC / UM_HZ;
 
 	if (setitimer(ITIMER_VIRTUAL, &time, &time) < 0)
 		printk(UM_KERN_ERR "disable_timer - setitimer failed, "
 		       "errno = %d\n", errno);
 
-	return timeval_to_ns(&time.it_value);
+	remain = timeval_to_ns(&time.it_value);
+	if (remain > max)
+		remain = max;
+
+	return remain;
 }
 
 long long os_nsecs(void)
@@ -79,7 +86,48 @@ static int after_sleep_interval(struct timespec *ts)
 {
 	return 0;
 }
+
+static void deliver_alarm(void)
+{
+	alarm_handler(SIGVTALRM, NULL);
+}
+
+static unsigned long long sleep_time(unsigned long long nsecs)
+{
+	return nsecs;
+}
+
 #else
+unsigned long long last_tick;
+unsigned long long skew;
+
+static void deliver_alarm(void)
+{
+	unsigned long long this_tick = os_nsecs();
+	int one_tick = UM_NSEC_PER_SEC / UM_HZ;
+
+	/* Protection against the host's time going backwards */
+	if ((last_tick != 0) && (this_tick < last_tick))
+		this_tick = last_tick;
+
+	if (last_tick == 0)
+		last_tick = this_tick - one_tick;
+
+	skew += this_tick - last_tick;
+
+	while (skew >= one_tick) {
+		alarm_handler(SIGVTALRM, NULL);
+		skew -= one_tick;
+	}
+
+	last_tick = this_tick;
+}
+
+static unsigned long long sleep_time(unsigned long long nsecs)
+{
+	return nsecs > skew ? nsecs - skew : 0;
+}
+
 static inline long long timespec_to_us(const struct timespec *ts)
 {
 	return ((long long) ts->tv_sec * UM_USEC_PER_SEC) +
@@ -102,6 +150,11 @@ static int after_sleep_interval(struct timespec *ts)
 	 */
 	if (start_usecs > usec)
 		start_usecs = usec;
+
+	start_usecs -= skew / UM_NSEC_PER_USEC;
+	if (start_usecs < 0)
+		start_usecs = 0;
+
 	tv = ((struct timeval) { .tv_sec  = start_usecs / UM_USEC_PER_SEC,
 				 .tv_usec = start_usecs % UM_USEC_PER_SEC });
 	interval = ((struct itimerval) { { 0, usec }, tv });
@@ -113,8 +166,6 @@ static int after_sleep_interval(struct timespec *ts)
 }
 #endif
 
-extern void alarm_handler(int sig, struct sigcontext *sc);
-
 void idle_sleep(unsigned long long nsecs)
 {
 	struct timespec ts;
@@ -126,10 +177,12 @@ void idle_sleep(unsigned long long nsecs)
 	 */
 	if (nsecs == 0)
 		nsecs = UM_NSEC_PER_SEC / UM_HZ;
+
+	nsecs = sleep_time(nsecs);
 	ts = ((struct timespec) { .tv_sec	= nsecs / UM_NSEC_PER_SEC,
 				  .tv_nsec	= nsecs % UM_NSEC_PER_SEC });
 
 	if (nanosleep(&ts, &ts) == 0)
-		alarm_handler(SIGVTALRM, NULL);
+		deliver_alarm();
 	after_sleep_interval(&ts);
 }
diff --git a/arch/um/sys-i386/ptrace.c b/arch/um/sys-i386/ptrace.c
index 6b4499906a6..c9b176534d6 100644
--- a/arch/um/sys-i386/ptrace.c
+++ b/arch/um/sys-i386/ptrace.c
@@ -148,14 +148,13 @@ int peek_user(struct task_struct *child, long addr, long data)
 int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
 {
 	int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
-	long fpregs[HOST_FP_SIZE];
+	struct user_i387_struct fpregs;
 
-	BUG_ON(sizeof(*buf) != sizeof(fpregs));
-	err = save_fp_registers(userspace_pid[cpu], fpregs);
+	err = save_fp_registers(userspace_pid[cpu], (unsigned long *) &fpregs);
 	if (err)
 		return err;
 
-	n = copy_to_user(buf, fpregs, sizeof(fpregs));
+	n = copy_to_user(buf, &fpregs, sizeof(fpregs));
 	if(n > 0)
 		return -EFAULT;
 
@@ -165,27 +164,26 @@ int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
 int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
 {
 	int n, cpu = ((struct thread_info *) child->stack)->cpu;
-	long fpregs[HOST_FP_SIZE];
+	struct user_i387_struct fpregs;
 
-	BUG_ON(sizeof(*buf) != sizeof(fpregs));
-	n = copy_from_user(fpregs, buf, sizeof(fpregs));
+	n = copy_from_user(&fpregs, buf, sizeof(fpregs));
 	if (n > 0)
 		return -EFAULT;
 
-	return restore_fp_registers(userspace_pid[cpu], fpregs);
+	return restore_fp_registers(userspace_pid[cpu],
+				    (unsigned long *) &fpregs);
 }
 
 int get_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
 {
 	int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
-	long fpregs[HOST_XFP_SIZE];
+	struct user_fxsr_struct fpregs;
 
-	BUG_ON(sizeof(*buf) != sizeof(fpregs));
-	err = save_fpx_registers(userspace_pid[cpu], fpregs);
+	err = save_fpx_registers(userspace_pid[cpu], (unsigned long *) &fpregs);
 	if (err)
 		return err;
 
-	n = copy_to_user(buf, fpregs, sizeof(fpregs));
+	n = copy_to_user(buf, &fpregs, sizeof(fpregs));
 	if(n > 0)
 		return -EFAULT;
 
@@ -195,14 +193,14 @@ int get_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
 int set_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
 {
 	int n, cpu = ((struct thread_info *) child->stack)->cpu;
-	long fpregs[HOST_XFP_SIZE];
+	struct user_fxsr_struct fpregs;
 
-	BUG_ON(sizeof(*buf) != sizeof(fpregs));
-	n = copy_from_user(fpregs, buf, sizeof(fpregs));
+	n = copy_from_user(&fpregs, buf, sizeof(fpregs));
 	if (n > 0)
 		return -EFAULT;
 
-	return restore_fpx_registers(userspace_pid[cpu], fpregs);
+	return restore_fpx_registers(userspace_pid[cpu],
+				     (unsigned long *) &fpregs);
 }
 
 long subarch_ptrace(struct task_struct *child, long request, long addr,
diff --git a/arch/um/sys-i386/user-offsets.c b/arch/um/sys-i386/user-offsets.c
index 39bd32bf84f..5f883bfe773 100644
--- a/arch/um/sys-i386/user-offsets.c
+++ b/arch/um/sys-i386/user-offsets.c
@@ -22,7 +22,7 @@ void foo(void)
 	OFFSET(HOST_SC_CR2, sigcontext, cr2);
 
 	DEFINE_LONGS(HOST_FP_SIZE, sizeof(struct user_fpregs_struct));
-	DEFINE_LONGS(HOST_XFP_SIZE, sizeof(struct user_fpxregs_struct));
+	DEFINE_LONGS(HOST_FPX_SIZE, sizeof(struct user_fpxregs_struct));
 
 	DEFINE(HOST_IP, EIP);
 	DEFINE(HOST_SP, UESP);
diff --git a/arch/um/sys-x86_64/ksyms.c b/arch/um/sys-x86_64/ksyms.c
index 4d7d1a812d8..1db2fce0094 100644
--- a/arch/um/sys-x86_64/ksyms.c
+++ b/arch/um/sys-x86_64/ksyms.c
@@ -1,5 +1,11 @@
-#include "linux/module.h"
-#include "asm/string.h"
+#include <linux/module.h>
+#include <asm/string.h>
+#include <asm/checksum.h>
 
 /*XXX: we need them because they would be exported by x86_64 */
+#if (__GNUC__ == 4 && __GNUC_MINOR__ >= 3) || __GNUC__ > 4
+EXPORT_SYMBOL(memcpy);
+#else
 EXPORT_SYMBOL(__memcpy);
+#endif
+EXPORT_SYMBOL(csum_partial);
diff --git a/arch/um/sys-x86_64/user-offsets.c b/arch/um/sys-x86_64/user-offsets.c
index 2f3443c6e85..973585414a6 100644
--- a/arch/um/sys-x86_64/user-offsets.c
+++ b/arch/um/sys-x86_64/user-offsets.c
@@ -24,7 +24,6 @@ void foo(void)
 	OFFSET(HOST_SC_TRAPNO, sigcontext, trapno);
 
 	DEFINE(HOST_FP_SIZE, sizeof(struct _fpstate) / sizeof(unsigned long));
-	DEFINE(HOST_XFP_SIZE, 0);
 	DEFINE_LONGS(HOST_RBX, RBX);
 	DEFINE_LONGS(HOST_RCX, RCX);
 	DEFINE_LONGS(HOST_RDI, RDI);