--- linux-2.6.6/arch/um/kernel/process.c	2004-07-07 06:21:19.144801856 +0200
+++ linux-2.6.6/arch/um/kernel/process.c.sysemu	2004-07-07 06:21:09.136323376 +0200
@@ -41,6 +41,8 @@
 #include "skas_ptrace.h"
 #endif
 
+int sysemu_active=0;
+
 void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int))
 {
 	int flags = 0, pages;
@@ -230,12 +232,12 @@
 	printk("OK\n");
 
 #ifdef PTRACE_SYSEMU
-	printk("Checking syscall emulation patch for ptrace...");
+       printk("Checking syscall emulation patch for ptrace on HOST...");
 	use_sysemu = 0;
 	pid = start_ptraced_child(&stack);
 	if(ptrace(PTRACE_SYSEMU, pid, 0, 0) >= 0) {
-		struct user_regs_struct regs;
-
+  	 	struct user_regs_struct regs;
+ 
 		if (waitpid(pid, &status, WUNTRACED) < 0)
 			panic("check_ptrace : wait failed, errno = %d", errno);
 		if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
@@ -252,18 +254,44 @@
 
 		stop_ptraced_child(pid, stack, 0);
 
-		printk("OK\n");
-		use_sysemu = 1;
-	}
-	else
-	{
-		printk("missing\n");
+		printk("Found!\n");
+                printk("Syscall emulation is...");
+                if(sysemu_active) {
+         	 use_sysemu = 1;
+                 printk("On!\n"); 
+                }           
+                else {
+                 use_sysemu = 0;
+                 printk("Off!\n");  
+                }          
+     
+	 }
+	 else
+	 {
+	 	printk("Missing!\n");
+                if(sysemu_active) {
+                 printk("Notice: You cannot use syscall emulation on this host!\n");
+                }
 		stop_ptraced_child(pid, stack, 1);
-	}
-
+	 }
+        
+        
 # endif /* PTRACE_SYSEMU */
 }
 
+
+static void sysemufnc(char *str)
+{
+ sysemu_active=1;
+}
+
+__uml_setup("sysemu",sysemufnc,
+"sysemu\n    Turn syscall emulation patch for ptrace (SYSEMU) on.\n"
+"    SYSEMU is a performance-patch introduced by Laurent Vivier. It changes\n"
+"    behaviour of ptrace() and helps reducing host context switch rate.\n"
+"    To make it working, you need a kernel patch for your host, too.\n"
+"    See http://perso.wanadoo.fr/laurent.vivier/UML/ for further information.\n\n");
+
 int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr)
 {
 	jmp_buf buf;