Merge commit 'v3.5-rc5' into next

28 files changed, 83 insertions, 148 deletions

diff --git a/arch/um/Kconfig.common b/arch/um/Kconfig.common
index 20a49ba93cb9..cb837c223922 100644
--- a/arch/um/Kconfig.common
+++ b/arch/um/Kconfig.common
@@ -10,6 +10,7 @@ config UML
 	select GENERIC_IRQ_SHOW
 	select GENERIC_CPU_DEVICES
 	select GENERIC_IO
+	select GENERIC_CLOCKEVENTS
 
 config MMU
 	bool
@@ -52,15 +53,6 @@ config GENERIC_BUG
 	default y
 	depends on BUG
 
-config GENERIC_CLOCKEVENTS
-	bool
-	default y
-
-# Used in kernel/irq/manage.c and include/linux/irq.h
-config IRQ_RELEASE_METHOD
-	bool
-	default y
-
 config HZ
 	int
 	default 100
diff --git a/arch/um/Kconfig.um b/arch/um/Kconfig.um
index 70fd690964e4..bf87f25eb2de 100644
--- a/arch/um/Kconfig.um
+++ b/arch/um/Kconfig.um
@@ -10,7 +10,6 @@ config STATIC_LINK
 	  2.75G) for UML.
 
 source "mm/Kconfig"
-source "kernel/time/Kconfig"
 
 config LD_SCRIPT_STATIC
 	bool
diff --git a/arch/um/Makefile b/arch/um/Makefile
index 55c0661e2b5d..097091059aaa 100644
--- a/arch/um/Makefile
+++ b/arch/um/Makefile
@@ -121,15 +121,8 @@ LINK_WRAPS = -Wl,--wrap,malloc -Wl,--wrap,free -Wl,--wrap,calloc
 
 LD_FLAGS_CMDLINE = $(foreach opt,$(LDFLAGS),-Wl,$(opt))
 
-CFLAGS_vmlinux := $(LINK-y) $(LINK_WRAPS) $(LD_FLAGS_CMDLINE)
-define cmd_vmlinux__
-	$(CC) $(CFLAGS_vmlinux) -o $@ \
-	-Wl,-T,$(vmlinux-lds) $(vmlinux-init) \
-	-Wl,--start-group $(vmlinux-main) -Wl,--end-group \
-	-lutil \
-	$(filter-out $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o \
-	FORCE ,$^) ; rm -f linux
-endef
+# Used by link-vmlinux.sh which has special support for um link
+export CFLAGS_vmlinux := $(LINK-y) $(LINK_WRAPS) $(LD_FLAGS_CMDLINE)
 
 # When cleaning we don't include .config, so we don't include
 # TT or skas makefiles and don't clean skas_ptregs.h.
diff --git a/arch/um/defconfig b/arch/um/defconfig
index fdc97e2c3d73..7823ab12e6a4 100644
--- a/arch/um/defconfig
+++ b/arch/um/defconfig
@@ -12,7 +12,6 @@ CONFIG_LOCKDEP_SUPPORT=y
 CONFIG_GENERIC_CALIBRATE_DELAY=y
 CONFIG_GENERIC_BUG=y
 CONFIG_GENERIC_CLOCKEVENTS=y
-CONFIG_IRQ_RELEASE_METHOD=y
 CONFIG_HZ=100
 
 #
diff --git a/arch/um/drivers/chan_kern.c b/arch/um/drivers/chan_kern.c
index ca4c7ebfd0aa..45e248c2f43c 100644
--- a/arch/um/drivers/chan_kern.c
+++ b/arch/um/drivers/chan_kern.c
@@ -8,6 +8,7 @@
 #include <linux/tty_flip.h>
 #include "chan.h"
 #include "os.h"
+#include "irq_kern.h"
 
 #ifdef CONFIG_NOCONFIG_CHAN
 static void *not_configged_init(char *str, int device,
@@ -213,9 +214,9 @@ void free_irqs(void)
 		chan = list_entry(ele, struct chan, free_list);
 
 		if (chan->input && chan->enabled)
-			free_irq(chan->line->driver->read_irq, chan);
+			um_free_irq(chan->line->driver->read_irq, chan);
 		if (chan->output && chan->enabled)
-			free_irq(chan->line->driver->write_irq, chan);
+			um_free_irq(chan->line->driver->write_irq, chan);
 		chan->enabled = 0;
 	}
 }
@@ -234,9 +235,9 @@ static void close_one_chan(struct chan *chan, int delay_free_irq)
 	}
 	else {
 		if (chan->input && chan->enabled)
-			free_irq(chan->line->driver->read_irq, chan);
+			um_free_irq(chan->line->driver->read_irq, chan);
 		if (chan->output && chan->enabled)
-			free_irq(chan->line->driver->write_irq, chan);
+			um_free_irq(chan->line->driver->write_irq, chan);
 		chan->enabled = 0;
 	}
 	if (chan->ops->close != NULL)
diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c
index 4ab0d9c0911c..acfd0e0fd0c9 100644
--- a/arch/um/drivers/line.c
+++ b/arch/um/drivers/line.c
@@ -699,7 +699,7 @@ struct winch {
 static void __free_winch(struct work_struct *work)
 {
 	struct winch *winch = container_of(work, struct winch, work);
-	free_irq(WINCH_IRQ, winch);
+	um_free_irq(WINCH_IRQ, winch);
 
 	if (winch->pid != -1)
 		os_kill_process(winch->pid, 1);
diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index 43b39d61b538..88e466b159dc 100644
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -705,6 +705,7 @@ static void stack_proc(void *arg)
 	struct task_struct *from = current, *to = arg;
 
 	to->thread.saved_task = from;
+	rcu_switch_from(from);
 	switch_to(from, to, from);
 }
 
diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c
index 95f4416e6d9f..0d60c5685c26 100644
--- a/arch/um/drivers/net_kern.c
+++ b/arch/um/drivers/net_kern.c
@@ -195,7 +195,7 @@ static int uml_net_close(struct net_device *dev)
 
 	netif_stop_queue(dev);
 
-	free_irq(dev->irq, dev);
+	um_free_irq(dev->irq, dev);
 	if (lp->close != NULL)
 		(*lp->close)(lp->fd, &lp->user);
 	lp->fd = -1;
@@ -835,7 +835,7 @@ static void close_devices(void)
 	spin_lock(&opened_lock);
 	list_for_each(ele, &opened) {
 		lp = list_entry(ele, struct uml_net_private, list);
-		free_irq(lp->dev->irq, lp->dev);
+		um_free_irq(lp->dev->irq, lp->dev);
 		if ((lp->close != NULL) && (lp->fd >= 0))
 			(*lp->close)(lp->fd, &lp->user);
 		if (lp->remove != NULL)
diff --git a/arch/um/drivers/port_kern.c b/arch/um/drivers/port_kern.c
index e31680e662a4..11866ffd45a9 100644
--- a/arch/um/drivers/port_kern.c
+++ b/arch/um/drivers/port_kern.c
@@ -254,7 +254,7 @@ int port_wait(void *data)
 		 * connection.  Then we loop here throwing out failed
 		 * connections until a good one is found.
 		 */
-		free_irq(TELNETD_IRQ, conn);
+		um_free_irq(TELNETD_IRQ, conn);
 
 		if (conn->fd >= 0)
 			break;
diff --git a/arch/um/drivers/xterm_kern.c b/arch/um/drivers/xterm_kern.c
index 8bd130f0bda3..b68bbe269e01 100644
--- a/arch/um/drivers/xterm_kern.c
+++ b/arch/um/drivers/xterm_kern.c
@@ -65,7 +65,7 @@ int xterm_fd(int socket, int *pid_out)
 	 * isn't set) this will hang... */
 	wait_for_completion(&data->ready);
 
-	free_irq(XTERM_IRQ, data);
+	um_free_irq(XTERM_IRQ, data);
 
 	ret = data->new_fd;
 	*pid_out = data->pid;
diff --git a/arch/um/include/asm/kvm_para.h b/arch/um/include/asm/kvm_para.h
new file mode 100644
index 000000000000..14fab8f0b957
--- /dev/null
+++ b/arch/um/include/asm/kvm_para.h
@@ -0,0 +1 @@
+#include <asm-generic/kvm_para.h>
diff --git a/arch/um/include/asm/pgtable.h b/arch/um/include/asm/pgtable.h
index 6a3f9845743e..5888f1b83477 100644
--- a/arch/um/include/asm/pgtable.h
+++ b/arch/um/include/asm/pgtable.h
@@ -273,6 +273,12 @@ static inline void set_pte(pte_t *pteptr, pte_t pteval)
 }
 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
 
+#define __HAVE_ARCH_PTE_SAME
+static inline int pte_same(pte_t pte_a, pte_t pte_b)
+{
+	return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE);
+}
+
 /*
  * Conversion functions: convert a page and protection to a page entry,
  * and a page entry and page directory to the page they refer to.
@@ -348,11 +354,11 @@ extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
 #define update_mmu_cache(vma,address,ptep) do ; while (0)
 
 /* Encode and de-code a swap entry */
-#define __swp_type(x)			(((x).val >> 4) & 0x3f)
+#define __swp_type(x)			(((x).val >> 5) & 0x1f)
 #define __swp_offset(x)			((x).val >> 11)
 
 #define __swp_entry(type, offset) \
-	((swp_entry_t) { ((type) << 4) | ((offset) << 11) })
+	((swp_entry_t) { ((type) << 5) | ((offset) << 11) })
 #define __pte_to_swp_entry(pte) \
 	((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
diff --git a/arch/um/include/asm/processor-generic.h b/arch/um/include/asm/processor-generic.h
index 98d01bc4fa92..69f1c57a8d0d 100644
--- a/arch/um/include/asm/processor-generic.h
+++ b/arch/um/include/asm/processor-generic.h
@@ -68,19 +68,12 @@ struct thread_struct {
 	.request		= { 0 } \
 }
 
-extern struct task_struct *alloc_task_struct_node(int node);
-
 static inline void release_thread(struct task_struct *task)
 {
 }
 
 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
 
-static inline void prepare_to_copy(struct task_struct *tsk)
-{
-}
-
-
 extern unsigned long thread_saved_pc(struct task_struct *t);
 
 static inline void mm_copy_segments(struct mm_struct *from_mm,
diff --git a/arch/um/include/asm/thread_info.h b/arch/um/include/asm/thread_info.h
index 200c4ab1240c..c04e5ab68f56 100644
--- a/arch/um/include/asm/thread_info.h
+++ b/arch/um/include/asm/thread_info.h
@@ -71,6 +71,7 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_MEMDIE		5	/* is terminating due to OOM killer */
 #define TIF_SYSCALL_AUDIT	6
 #define TIF_RESTORE_SIGMASK	7
+#define TIF_NOTIFY_RESUME	8
 
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
@@ -78,6 +79,5 @@ static inline struct thread_info *current_thread_info(void)
 #define _TIF_POLLING_NRFLAG     (1 << TIF_POLLING_NRFLAG)
 #define _TIF_MEMDIE		(1 << TIF_MEMDIE)
 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
-#define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
 
 #endif
diff --git a/arch/um/include/shared/frame_kern.h b/arch/um/include/shared/frame_kern.h
index 76078490c258..e584e40ee832 100644
--- a/arch/um/include/shared/frame_kern.h
+++ b/arch/um/include/shared/frame_kern.h
@@ -6,9 +6,6 @@
 #ifndef __FRAME_KERN_H_
 #define __FRAME_KERN_H_
 
-#define _S(nr) (1<<((nr)-1))
-#define _BLOCKABLE (~(_S(SIGKILL) | _S(SIGSTOP)))
-
 extern int setup_signal_stack_sc(unsigned long stack_top, int sig, 
 				 struct k_sigaction *ka,
 				 struct pt_regs *regs, 
diff --git a/arch/um/include/shared/irq_kern.h b/arch/um/include/shared/irq_kern.h
index b05d22f3d84e..7a5bfa6291b8 100644
--- a/arch/um/include/shared/irq_kern.h
+++ b/arch/um/include/shared/irq_kern.h
@@ -13,6 +13,6 @@ extern int um_request_irq(unsigned int irq, int fd, int type,
 			  irq_handler_t handler,
 			  unsigned long irqflags,  const char * devname,
 			  void *dev_id);
-
+void um_free_irq(unsigned int irq, void *dev);
 #endif
 
diff --git a/arch/um/kernel/Makefile b/arch/um/kernel/Makefile
index 65a1c3d690ea..babe21826e3e 100644
--- a/arch/um/kernel/Makefile
+++ b/arch/um/kernel/Makefile
@@ -10,7 +10,7 @@ CPPFLAGS_vmlinux.lds := -DSTART=$(LDS_START)		\
 extra-y := vmlinux.lds
 clean-files :=
 
-obj-y = config.o exec.o exitcode.o init_task.o irq.o ksyms.o mem.o \
+obj-y = config.o exec.o exitcode.o irq.o ksyms.o mem.o \
 	physmem.o process.o ptrace.o reboot.o sigio.o \
 	signal.o smp.o syscall.o sysrq.o time.o tlb.o trap.o \
 	um_arch.o umid.o skas/
diff --git a/arch/um/kernel/init_task.c b/arch/um/kernel/init_task.c
deleted file mode 100644
index ddc9698b66ed..000000000000
--- a/arch/um/kernel/init_task.c
+++ /dev/null
@@ -1,38 +0,0 @@
-/*
- * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,intel.linux}.com)
- * Licensed under the GPL
- */
-
-#include "linux/sched.h"
-#include "linux/init_task.h"
-#include "linux/fs.h"
-#include "linux/module.h"
-#include "linux/mqueue.h"
-#include "asm/uaccess.h"
-
-static struct signal_struct init_signals = INIT_SIGNALS(init_signals);
-static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand);
-/*
- * Initial task structure.
- *
- * All other task structs will be allocated on slabs in fork.c
- */
-
-struct task_struct init_task = INIT_TASK(init_task);
-
-EXPORT_SYMBOL(init_task);
-
-/*
- * Initial thread structure.
- *
- * We need to make sure that this is aligned due to the
- * way process stacks are handled. This is done by having a special
- * "init_task" linker map entry..
- */
-
-union thread_union init_thread_union __init_task_data =
-	{ INIT_THREAD_INFO(init_task) };
-
-union thread_union cpu0_irqstack
-	__attribute__((__section__(".data..init_irqstack"))) =
-		{ INIT_THREAD_INFO(init_task) };
diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c
index 71b8c947e5ef..00506c3d5d6e 100644
--- a/arch/um/kernel/irq.c
+++ b/arch/um/kernel/irq.c
@@ -297,6 +297,13 @@ unsigned int do_IRQ(int irq, struct uml_pt_regs *regs)
 	return 1;
 }
 
+void um_free_irq(unsigned int irq, void *dev)
+{
+	free_irq_by_irq_and_dev(irq, dev);
+	free_irq(irq, dev);
+}
+EXPORT_SYMBOL(um_free_irq);
+
 int um_request_irq(unsigned int irq, int fd, int type,
 		   irq_handler_t handler,
 		   unsigned long irqflags, const char * devname,
@@ -327,7 +334,6 @@ static void dummy(struct irq_data *d)
 /* This is used for everything else than the timer. */
 static struct irq_chip normal_irq_type = {
 	.name = "SIGIO",
-	.release = free_irq_by_irq_and_dev,
 	.irq_disable = dummy,
 	.irq_enable = dummy,
 	.irq_ack = dummy,
@@ -335,7 +341,6 @@ static struct irq_chip normal_irq_type = {
 
 static struct irq_chip SIGVTALRM_irq_type = {
 	.name = "SIGVTALRM",
-	.release = free_irq_by_irq_and_dev,
 	.irq_disable = dummy,
 	.irq_enable = dummy,
 	.irq_ack = dummy,
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 2b73dedb44ca..ccb9a9d283f1 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -18,6 +18,7 @@
 #include <linux/seq_file.h>
 #include <linux/tick.h>
 #include <linux/threads.h>
+#include <linux/tracehook.h>
 #include <asm/current.h>
 #include <asm/pgtable.h>
 #include <asm/mmu_context.h>
@@ -114,8 +115,10 @@ void interrupt_end(void)
 {
 	if (need_resched())
 		schedule();
-	if (test_tsk_thread_flag(current, TIF_SIGPENDING))
+	if (test_thread_flag(TIF_SIGPENDING))
 		do_signal();
+	if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME))
+		tracehook_notify_resume(&current->thread.regs);
 }
 
 void exit_thread(void)
@@ -190,7 +193,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
 	if (current->thread.forking) {
 	  	memcpy(&p->thread.regs.regs, &regs->regs,
 		       sizeof(p->thread.regs.regs));
-		REGS_SET_SYSCALL_RETURN(p->thread.regs.regs.gp, 0);
+		UPT_SET_SYSCALL_RETURN(&p->thread.regs.regs, 0);
 		if (sp != 0)
 			REGS_SP(p->thread.regs.regs.gp) = sp;
 
diff --git a/arch/um/kernel/reboot.c b/arch/um/kernel/reboot.c
index 4d93dff6b371..3d15243ce692 100644
--- a/arch/um/kernel/reboot.c
+++ b/arch/um/kernel/reboot.c
@@ -4,7 +4,9 @@
  */
 
 #include "linux/sched.h"
+#include "linux/spinlock.h"
 #include "linux/slab.h"
+#include "linux/oom.h"
 #include "kern_util.h"
 #include "os.h"
 #include "skas.h"
@@ -22,13 +24,18 @@ static void kill_off_processes(void)
 		struct task_struct *p;
 		int pid;
 
+		read_lock(&tasklist_lock);
 		for_each_process(p) {
-			if (p->mm == NULL)
-				continue;
+			struct task_struct *t;
 
-			pid = p->mm->context.id.u.pid;
+			t = find_lock_task_mm(p);
+			if (!t)
+				continue;
+			pid = t->mm->context.id.u.pid;
+			task_unlock(t);
 			os_kill_ptraced_process(pid, 1);
 		}
+		read_unlock(&tasklist_lock);
 	}
 }
 
diff --git a/arch/um/kernel/signal.c b/arch/um/kernel/signal.c
index fb12f4c5e649..7362d58efc29 100644
--- a/arch/um/kernel/signal.c
+++ b/arch/um/kernel/signal.c
@@ -15,23 +15,16 @@
 EXPORT_SYMBOL(block_signals);
 EXPORT_SYMBOL(unblock_signals);
 
-#define _S(nr) (1<<((nr)-1))
-
-#define _BLOCKABLE (~(_S(SIGKILL) | _S(SIGSTOP)))
-
 /*
  * OK, we're invoking a handler
  */
-static int handle_signal(struct pt_regs *regs, unsigned long signr,
-			 struct k_sigaction *ka, siginfo_t *info,
-			 sigset_t *oldset)
+static void handle_signal(struct pt_regs *regs, unsigned long signr,
+			 struct k_sigaction *ka, siginfo_t *info)
 {
+	sigset_t *oldset = sigmask_to_save();
 	unsigned long sp;
 	int err;
 
-	/* Always make any pending restarted system calls return -EINTR */
-	current_thread_info()->restart_block.fn = do_no_restart_syscall;
-
 	/* Did we come from a system call? */
 	if (PT_REGS_SYSCALL_NR(regs) >= 0) {
 		/* If so, check system call restarting.. */
@@ -68,37 +61,19 @@ static int handle_signal(struct pt_regs *regs, unsigned long signr,
 	if (err)
 		force_sigsegv(signr, current);
 	else
-		block_sigmask(ka, signr);
-
-	return err;
+		signal_delivered(signr, info, ka, regs, 0);
 }
 
 static int kern_do_signal(struct pt_regs *regs)
 {
 	struct k_sigaction ka_copy;
 	siginfo_t info;
-	sigset_t *oldset;
 	int sig, handled_sig = 0;
 
-	if (test_thread_flag(TIF_RESTORE_SIGMASK))
-		oldset = &current->saved_sigmask;
-	else
-		oldset = &current->blocked;
-
 	while ((sig = get_signal_to_deliver(&info, &ka_copy, regs, NULL)) > 0) {
 		handled_sig = 1;
 		/* Whee!  Actually deliver the signal.  */
-		if (!handle_signal(regs, sig, &ka_copy, &info, oldset)) {
-			/*
-			 * a signal was successfully delivered; the saved
-			 * sigmask will have been stored in the signal frame,
-			 * and will be restored by sigreturn, so we can simply
-			 * clear the TIF_RESTORE_SIGMASK flag
-			 */
-			if (test_thread_flag(TIF_RESTORE_SIGMASK))
-				clear_thread_flag(TIF_RESTORE_SIGMASK);
-			break;
-		}
+		handle_signal(regs, sig, &ka_copy, &info);
 	}
 
 	/* Did we come from a system call? */
@@ -134,10 +109,8 @@ static int kern_do_signal(struct pt_regs *regs)
 	 * if there's no signal to deliver, we just put the saved sigmask
 	 * back
 	 */
-	if (!handled_sig && test_thread_flag(TIF_RESTORE_SIGMASK)) {
-		clear_thread_flag(TIF_RESTORE_SIGMASK);
-		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
-	}
+	if (!handled_sig)
+		restore_saved_sigmask();
 	return handled_sig;
 }
 
@@ -152,15 +125,8 @@ int do_signal(void)
 long sys_sigsuspend(int history0, int history1, old_sigset_t mask)
 {
 	sigset_t blocked;
-
-	mask &= _BLOCKABLE;
 	siginitset(&blocked, mask);
-	set_current_blocked(&blocked);
-
-	current->state = TASK_INTERRUPTIBLE;
-	schedule();
-	set_thread_flag(TIF_RESTORE_SIGMASK);
-	return -ERESTARTNOHAND;
+	return sigsuspend(&blocked);
 }
 
 long sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
diff --git a/arch/um/kernel/skas/syscall.c b/arch/um/kernel/skas/syscall.c
index f5173e1ec3ac..05fbeb480e0b 100644
--- a/arch/um/kernel/skas/syscall.c
+++ b/arch/um/kernel/skas/syscall.c
@@ -34,7 +34,7 @@ void handle_syscall(struct uml_pt_regs *r)
 		result = -ENOSYS;
 	else result = EXECUTE_SYSCALL(syscall, regs);
 
-	REGS_SET_SYSCALL_RETURN(r->gp, result);
+	UPT_SET_SYSCALL_RETURN(r, result);
 
 	syscall_trace(r, 1);
 }
diff --git a/arch/um/kernel/smp.c b/arch/um/kernel/smp.c
index 6f588e160fb0..a02b7e9e6b94 100644
--- a/arch/um/kernel/smp.c
+++ b/arch/um/kernel/smp.c
@@ -140,7 +140,7 @@ void smp_prepare_boot_cpu(void)
 	set_cpu_online(smp_processor_id(), true);
 }
 
-int __cpu_up(unsigned int cpu)
+int __cpu_up(unsigned int cpu, struct task_struct *tidle)
 {
 	cpu_set(cpu, smp_commenced_mask);
 	while (!cpu_online(cpu))
diff --git a/arch/um/kernel/tlb.c b/arch/um/kernel/tlb.c
index 7f3d4d86431a..f819af951c19 100644
--- a/arch/um/kernel/tlb.c
+++ b/arch/um/kernel/tlb.c
@@ -75,6 +75,7 @@ static int do_ops(struct host_vm_change *hvc, int end,
 		default:
 			printk(KERN_ERR "Unknown op type %d in do_ops\n",
 			       op->type);
+			BUG();
 			break;
 		}
 	}
diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c
index dafc94715950..3be60765c0e2 100644
--- a/arch/um/kernel/trap.c
+++ b/arch/um/kernel/trap.c
@@ -30,6 +30,8 @@ int handle_page_fault(unsigned long address, unsigned long ip,
 	pmd_t *pmd;
 	pte_t *pte;
 	int err = -EFAULT;
+	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE |
+				 (is_write ? FAULT_FLAG_WRITE : 0);
 
 	*code_out = SEGV_MAPERR;
 
@@ -40,6 +42,7 @@ int handle_page_fault(unsigned long address, unsigned long ip,
 	if (in_atomic())
 		goto out_nosemaphore;
 
+retry:
 	down_read(&mm->mmap_sem);
 	vma = find_vma(mm, address);
 	if (!vma)
@@ -65,7 +68,11 @@ good_area:
 	do {
 		int fault;
 
-		fault = handle_mm_fault(mm, vma, address, is_write ? FAULT_FLAG_WRITE : 0);
+		fault = handle_mm_fault(mm, vma, address, flags);
+
+		if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
+			goto out_nosemaphore;
+
 		if (unlikely(fault & VM_FAULT_ERROR)) {
 			if (fault & VM_FAULT_OOM) {
 				goto out_of_memory;
@@ -75,10 +82,17 @@ good_area:
 			}
 			BUG();
 		}
-		if (fault & VM_FAULT_MAJOR)
-			current->maj_flt++;
-		else
-			current->min_flt++;
+		if (flags & FAULT_FLAG_ALLOW_RETRY) {
+			if (fault & VM_FAULT_MAJOR)
+				current->maj_flt++;
+			else
+				current->min_flt++;
+			if (fault & VM_FAULT_RETRY) {
+				flags &= ~FAULT_FLAG_ALLOW_RETRY;
+
+				goto retry;
+			}
+		}
 
 		pgd = pgd_offset(mm, address);
 		pud = pud_offset(pgd, address);
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index ba00eae45aad..4db8770906ca 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -10,6 +10,7 @@
 #include <linux/seq_file.h>
 #include <linux/string.h>
 #include <linux/utsname.h>
+#include <linux/sched.h>
 #include <asm/pgtable.h>
 #include <asm/processor.h>
 #include <asm/setup.h>
@@ -47,6 +48,10 @@ struct cpuinfo_um boot_cpu_data = {
 	.ipi_pipe		= { -1, -1 }
 };
 
+union thread_union cpu0_irqstack
+	__attribute__((__section__(".data..init_irqstack"))) =
+		{ INIT_THREAD_INFO(init_task) };
+
 unsigned long thread_saved_pc(struct task_struct *task)
 {
 	/* FIXME: Need to look up userspace_pid by cpu */
diff --git a/arch/um/os-Linux/skas/mem.c b/arch/um/os-Linux/skas/mem.c
index c0afff7af4bd..90b310d29179 100644
--- a/arch/um/os-Linux/skas/mem.c
+++ b/arch/um/os-Linux/skas/mem.c
@@ -48,10 +48,6 @@ __initcall(init_syscall_regs);
 
 extern int proc_mm;
 
-int single_count = 0;
-int multi_count = 0;
-int multi_op_count = 0;
-
 static inline long do_syscall_stub(struct mm_id * mm_idp, void **addr)
 {
 	int n, i;
@@ -64,8 +60,6 @@ static inline long do_syscall_stub(struct mm_id * mm_idp, void **addr)
 		/* FIXME: Need to look up userspace_pid by cpu */
 		pid = userspace_pid[0];
 
-	multi_count++;
-
 	n = ptrace_setregs(pid, syscall_regs);
 	if (n < 0) {
 		printk(UM_KERN_ERR "Registers - \n");
@@ -126,9 +120,6 @@ long run_syscall_stub(struct mm_id * mm_idp, int syscall,
 {
 	unsigned long *stack = check_init_stack(mm_idp, *addr);
 
-	if (done && *addr == NULL)
-		single_count++;
-
 	*stack += sizeof(long);
 	stack += *stack / sizeof(long);
 
@@ -141,7 +132,6 @@ long run_syscall_stub(struct mm_id * mm_idp, int syscall,
 	*stack++ = args[5];
 	*stack++ = expected;
 	*stack = 0;
-	multi_op_count++;
 
 	if (!done && ((((unsigned long) stack) & ~UM_KERN_PAGE_MASK) <
 		     UM_KERN_PAGE_SIZE - 10 * sizeof(long))) {