diff -Naur host/arch/i386/config.in host-ptrace/arch/i386/config.in
--- host/arch/i386/config.in	Fri Aug  9 15:57:14 2002
+++ host-ptrace/arch/i386/config.in	Sun Nov 10 18:40:09 2002
@@ -291,6 +291,8 @@
    bool '    Use real mode APM BIOS call to power off' CONFIG_APM_REAL_MODE_POWER_OFF
 fi
 
+bool '/proc/mm' CONFIG_PROC_MM
+
 endmenu
 
 source drivers/mtd/Config.in
diff -Naur host/arch/i386/kernel/ldt.c host-ptrace/arch/i386/kernel/ldt.c
--- host/arch/i386/kernel/ldt.c	Fri Oct 26 00:01:41 2001
+++ host-ptrace/arch/i386/kernel/ldt.c	Sun Nov  3 18:37:48 2002
@@ -24,11 +24,12 @@
  * assured by user-space anyway. Writes are atomic, to protect
  * the security checks done on new descriptors.
  */
-static int read_ldt(void * ptr, unsigned long bytecount)
+static int read_ldt(struct task_struct *task, void * ptr, 
+		    unsigned long bytecount)
 {
 	int err;
 	unsigned long size;
-	struct mm_struct * mm = current->mm;
+	struct mm_struct * mm = task->mm;
 
 	err = 0;
 	if (!mm->context.segments)
@@ -64,9 +65,10 @@
 	return err;
 }
 
-static int write_ldt(void * ptr, unsigned long bytecount, int oldmode)
+static int write_ldt(struct task_struct *task, void * ptr, 
+		     unsigned long bytecount, int oldmode)
 {
-	struct mm_struct * mm = current->mm;
+	struct mm_struct * mm = task->mm;
 	__u32 entry_1, entry_2, *lp;
 	int error;
 	struct modify_ldt_ldt_s ldt_info;
@@ -148,23 +150,29 @@
 	return error;
 }
 
-asmlinkage int sys_modify_ldt(int func, void *ptr, unsigned long bytecount)
+int modify_ldt(struct task_struct *task, int func, void *ptr, 
+	       unsigned long bytecount)
 {
 	int ret = -ENOSYS;
 
 	switch (func) {
 	case 0:
-		ret = read_ldt(ptr, bytecount);
+		ret = read_ldt(task, ptr, bytecount);
 		break;
 	case 1:
-		ret = write_ldt(ptr, bytecount, 1);
+		ret = write_ldt(task, ptr, bytecount, 1);
 		break;
 	case 2:
 		ret = read_default_ldt(ptr, bytecount);
 		break;
 	case 0x11:
-		ret = write_ldt(ptr, bytecount, 0);
+		ret = write_ldt(task, ptr, bytecount, 0);
 		break;
 	}
 	return ret;
+}
+
+asmlinkage int sys_modify_ldt(int func, void *ptr, unsigned long bytecount)
+{
+	return(modify_ldt(current, func, ptr, bytecount));
 }
diff -Naur host/arch/i386/kernel/process.c host-ptrace/arch/i386/kernel/process.c
--- host/arch/i386/kernel/process.c	Fri Aug  9 15:57:14 2002
+++ host-ptrace/arch/i386/kernel/process.c	Wed Nov  6 22:12:45 2002
@@ -551,13 +551,11 @@
  * we do not have to muck with descriptors here, that is
  * done in switch_mm() as needed.
  */
-void copy_segments(struct task_struct *p, struct mm_struct *new_mm)
+void mm_copy_segments(struct mm_struct *old_mm, struct mm_struct *new_mm)
 {
-	struct mm_struct * old_mm;
 	void *old_ldt, *ldt;
 
 	ldt = NULL;
-	old_mm = current->mm;
 	if (old_mm && (old_ldt = old_mm->context.segments) != NULL) {
 		/*
 		 * Completely new LDT, we initialize it from the parent:
@@ -570,6 +568,16 @@
 	}
 	new_mm->context.segments = ldt;
 	new_mm->context.cpuvalid = ~0UL;	/* valid on all CPU's - they can't have stale data */
+}
+
+void copy_segments(struct task_struct *p, struct mm_struct *new_mm)
+{
+	mm_copy_segments(current->mm, new_mm);
+}
+
+void copy_task_segments(struct task_struct *from, struct mm_struct *new_mm)
+{
+	mm_copy_segments(from->mm, new_mm);
 }
 
 /*
diff -Naur host/arch/i386/kernel/ptrace.c host-ptrace/arch/i386/kernel/ptrace.c
--- host/arch/i386/kernel/ptrace.c	Fri Aug  9 15:57:14 2002
+++ host-ptrace/arch/i386/kernel/ptrace.c	Mon Nov 11 19:03:38 2002
@@ -147,6 +147,11 @@
 	put_stack_long(child, EFL_OFFSET, tmp);
 }
 
+extern int modify_ldt(struct task_struct *task, int func, void *ptr, 
+		      unsigned long bytecount);
+
+extern struct mm_struct *proc_mm_get_mm(int fd);
+
 asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
 {
 	struct task_struct *child;
@@ -415,10 +420,57 @@
 			child->ptrace |= PT_TRACESYSGOOD;
 		else
 			child->ptrace &= ~PT_TRACESYSGOOD;
+		ret = 0;
+		break;
+	}
+
+	case PTRACE_FAULTINFO: {
+		struct ptrace_faultinfo fault;
+
+		fault = ((struct ptrace_faultinfo) 
+			{ .is_write	= child->thread.error_code,
+			  .addr		= child->thread.cr2 });
+		ret = copy_to_user((unsigned long *) data, &fault, 
+				   sizeof(fault));
+		if(ret)
+			break;
+		break;
+	}
+	case PTRACE_SIGPENDING:
+		ret = copy_to_user((unsigned long *) data, 
+				   &child->pending.signal,
+				   sizeof(child->pending.signal));
+		break;
+
+	case PTRACE_LDT: {
+		struct ptrace_ldt ldt;
+
+		if(copy_from_user(&ldt, (unsigned long *) data, 
+				  sizeof(ldt))){
+			ret = -EIO;
+			break;
+		}
+		ret = modify_ldt(child, ldt.func, ldt.ptr, ldt.bytecount);
+		break;
+	}
+#ifdef CONFIG_PROC_MM
+	case PTRACE_SWITCH_MM: {
+		struct mm_struct *old = child->mm;
+		struct mm_struct *new = proc_mm_get_mm(data);
+
+		if(IS_ERR(new)){
+			ret = PTR_ERR(new);
+			break;
+		}
+
+		atomic_inc(&new->mm_users);
+		child->mm = new;
+		child->active_mm = new;
+		mmput(old);
 		ret = 0;
 		break;
 	}
-
+#endif
 	default:
 		ret = -EIO;
 		break;
diff -Naur host/arch/i386/kernel/sys_i386.c host-ptrace/arch/i386/kernel/sys_i386.c
--- host/arch/i386/kernel/sys_i386.c	Mon Mar 19 15:35:09 2001
+++ host-ptrace/arch/i386/kernel/sys_i386.c	Mon Nov 11 17:23:25 2002
@@ -40,7 +40,7 @@
 }
 
 /* common code for old and new mmaps */
-static inline long do_mmap2(
+long do_mmap2(struct mm_struct *mm,
 	unsigned long addr, unsigned long len,
 	unsigned long prot, unsigned long flags,
 	unsigned long fd, unsigned long pgoff)
@@ -55,9 +55,9 @@
 			goto out;
 	}
 
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
+	down_write(&mm->mmap_sem);
+	error = do_mmap_pgoff(mm, file, addr, len, prot, flags, pgoff);
+	up_write(&mm->mmap_sem);
 
 	if (file)
 		fput(file);
@@ -69,7 +69,7 @@
 	unsigned long prot, unsigned long flags,
 	unsigned long fd, unsigned long pgoff)
 {
-	return do_mmap2(addr, len, prot, flags, fd, pgoff);
+	return do_mmap2(current->mm, addr, len, prot, flags, fd, pgoff);
 }
 
 /*
@@ -100,7 +100,7 @@
 	if (a.offset & ~PAGE_MASK)
 		goto out;
 
-	err = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
+	err = do_mmap2(current->mm, a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
 out:
 	return err;
 }
diff -Naur host/include/asm-i386/processor.h host-ptrace/include/asm-i386/processor.h
--- host/include/asm-i386/processor.h	Sun Nov 10 18:47:37 2002
+++ host-ptrace/include/asm-i386/processor.h	Mon Nov 11 17:33:30 2002
@@ -436,6 +436,8 @@
 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
 
 /* Copy and release all segment info associated with a VM */
+extern void mm_copy_segments(struct mm_struct *old_mm, 
+			     struct mm_struct *new_mm);
 extern void copy_segments(struct task_struct *p, struct mm_struct * mm);
 extern void release_segments(struct mm_struct * mm);
 
diff -Naur host/include/asm-i386/ptrace.h host-ptrace/include/asm-i386/ptrace.h
--- host/include/asm-i386/ptrace.h	Sun Sep 23 19:20:51 2001
+++ host-ptrace/include/asm-i386/ptrace.h	Sun Nov 10 18:36:22 2002
@@ -51,6 +51,22 @@
 
 #define PTRACE_SETOPTIONS         21
 
+struct ptrace_faultinfo {
+	int is_write;
+	unsigned long addr;
+};
+
+struct ptrace_ldt {
+	int func;
+  	void *ptr;
+	unsigned long bytecount;
+};
+
+#define PTRACE_FAULTINFO 52
+#define PTRACE_SIGPENDING 53
+#define PTRACE_LDT 54
+#define PTRACE_SWITCH_MM 55
+
 /* options set using PTRACE_SETOPTIONS */
 #define PTRACE_O_TRACESYSGOOD     0x00000001
 
--- linux-2.4.20/arch/um/include/skas_ptrace.h.orig	Sat Mar 15 23:38:50 2003
+++ linux-2.4.20/arch/um/include/skas_ptrace.h	Sun Mar 16 00:30:46 2003
@@ -6,6 +6,8 @@
 #ifndef __SKAS_PTRACE_H
 #define __SKAS_PTRACE_H
 
+#ifndef PTRACE_FAULTINFO
+
 struct ptrace_faultinfo {
 	int is_write;
 	unsigned long addr;
@@ -21,6 +23,8 @@
 #define PTRACE_SIGPENDING 53
 #define PTRACE_LDT 54
 #define PTRACE_SWITCH_MM 55
+
+#endif
 
 #endif
 
--- linux-2.4.21/arch/ppc/kernel/syscalls.c.orig	Mon Jun 30 18:15:41 2003
+++ linux-2.4.21/arch/ppc/kernel/syscalls.c	Mon Jun 30 18:15:47 2003
@@ -189,7 +189,7 @@
 	}
 
 	down_write(&current->mm->mmap_sem);
-	ret = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
+	ret = do_mmap_pgoff(current->mm, file, addr, len, prot, flags, pgoff);
 	up_write(&current->mm->mmap_sem);
 	if (file)
 		fput(file);
--- linux-2.4.21/arch/ia64/kernel/sys_ia64.c.orig	Mon Jun 30 18:19:24 2003
+++ linux-2.4.21/arch/ia64/kernel/sys_ia64.c	Mon Jun 30 18:19:48 2003
@@ -219,7 +219,7 @@
 	}
 
 	down_write(&current->mm->mmap_sem);
-	addr = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
+	addr = do_mmap_pgoff(current->mm, file, addr, len, prot, flags, pgoff);
 	up_write(&current->mm->mmap_sem);
 
 out:	if (file)
--- linux-2.4.21/arch/sparc/kernel/sys_sparc.c~	Tue Jul  1 14:29:46 2003
+++ linux-2.4.21/arch/sparc/kernel/sys_sparc.c	Tue Jul  1 20:26:26 2003
@@ -250,7 +250,7 @@
 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 
 	down_write(&current->mm->mmap_sem);
-	retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
+	retval = do_mmap_pgoff(current->mm, file, addr, len, prot, flags, pgoff);
 	up_write(&current->mm->mmap_sem);
 
 out_putf: