various kernel printing fixes

. remove some call cycles by low-level functions invoking printf(); e.g.
	  send_sig() gets a return value that the caller should check
	. reason: very-early-phase printf() would trigger a printf() causing
	  infinite recursion -> GPF
	. move serial initialization a little earlier so DEBUG_EXTRA works for
	  serial earlier (e.g. its first instance, for "cstart")
	. closes tracker item 583:
	  System Fails to Complete Startup with Verbose 2 and 3 Boot Parameters,
	  reported by Stephen Hatton / pikpik.

kernel/arch/i386/memory.c

@@ -551,7 +551,8 @@ static void vm_suspend(struct proc *caller, const struct proc *target,
 							
 	/* Connect caller on vmrequest wait queue. */	
 	if(!(caller->p_vmrequest.nextrequestor = vmrequest))
-		send_sig(VM_PROC_NR, SIGKMEM);
+		if(OK != send_sig(VM_PROC_NR, SIGKMEM))
+			panic("send_sig failed");
 	vmrequest = caller;
 }
 

kernel/proc.c

@@ -1779,25 +1779,11 @@ const int fatalflag;
 	 * succeed.
 	 */
 	*p = _ENDPOINT_P(e);
-	if(!isokprocn(*p)) {
-#if DEBUG_ENABLE_IPC_WARNINGS
-		printf("kernel:%s:%d: bad endpoint %d: proc %d out of range\n",
-		file, line, e, *p);
-#endif
-	} else if(isemptyn(*p)) {
-#if 0
-	printf("kernel:%s:%d: bad endpoint %d: proc %d empty\n", file, line, e, *p);
-#endif
-	} else if(proc_addr(*p)->p_endpoint != e) {
-#if DEBUG_ENABLE_IPC_WARNINGS
-		printf("kernel:%s:%d: bad endpoint %d: proc %d has ept %d (generation %d vs. %d)\n", file, line,
-		e, *p, proc_addr(*p)->p_endpoint,
-		_ENDPOINT_G(e), _ENDPOINT_G(proc_addr(*p)->p_endpoint));
-#endif
-	} else ok = 1;
-	if(!ok && fatalflag) {
+	ok = 0;
+	if(isokprocn(*p) && !isemptyn(*p) && proc_addr(*p)->p_endpoint == e)
+		ok = 1;
+	if(!ok && fatalflag)
 		panic("invalid endpoint: %d",  e);
-	}
 	return ok;
 }
 

kernel/proto.h

@@ -81,7 +81,7 @@ int get_priv(register struct proc *rc, int proc_type);
 void set_sendto_bit(const struct proc *rc, int id);
 void unset_sendto_bit(const struct proc *rc, int id);
 void fill_sendto_mask(const struct proc *rc, sys_map_t *map);
-void send_sig(endpoint_t proc_nr, int sig_nr);
+int send_sig(endpoint_t proc_nr, int sig_nr);
 void cause_sig(proc_nr_t proc_nr, int sig_nr);
 void sig_delay_done(struct proc *rp);
 void kernel_call(message *m_user, struct proc * caller);

kernel/start.c

@@ -56,6 +56,17 @@ void cstart(
   system_hz = DEFAULT_HZ;
 #endif
 
+#ifdef DEBUG_SERIAL
+  /* Intitialize serial debugging */
+  value = env_get(SERVARNAME);
+  if(value && atoi(value) == 0) {
+	do_serial_debug=1;
+
+  	value = env_get(SERBAUDVARNAME);
+  	if (value) serial_debug_baud = atoi(value);
+  }
+#endif
+
   DEBUGEXTRA(("cstart\n"));
 
   /* Record miscellaneous information for user-space servers. */
@@ -72,17 +83,6 @@ void cstart(
   for(h = 0; h < _LOAD_HISTORY; h++)
 	kloadinfo.proc_load_history[h] = 0;
 
-#ifdef DEBUG_SERIAL
-  /* Intitialize serial debugging */
-  value = env_get(SERVARNAME);
-  if(value && atoi(value) == 0) {
-	do_serial_debug=1;
-
-  	value = env_get(SERBAUDVARNAME);
-  	if (value) serial_debug_baud = atoi(value);
-  }
-#endif
-
 #ifdef USE_APIC
   value = env_get("no_apic");
   if(value)

kernel/system.c

@@ -360,7 +360,7 @@ void fill_sendto_mask(const struct proc *rp, sys_map_t *map)
 /*===========================================================================*
  *				send_sig				     *
  *===========================================================================*/
-void send_sig(endpoint_t ep, int sig_nr)
+int send_sig(endpoint_t ep, int sig_nr)
 {
 /* Notify a system process about a signal. This is straightforward. Simply
  * set the signal that is to be delivered in the pending signals map and 
@@ -370,11 +370,13 @@ void send_sig(endpoint_t ep, int sig_nr)
   int proc_nr;
 
   if(!isokendpt(ep, &proc_nr) || isemptyn(proc_nr))
-	panic("send_sig to empty process: %d",  ep);
+	return EINVAL;
 
   rp = proc_addr(proc_nr);
   sigaddset(&priv(rp)->s_sig_pending, sig_nr);
   mini_notify(proc_addr(SYSTEM), rp->p_endpoint);
+
+  return OK;
 }
 
 /*===========================================================================*
@@ -425,7 +427,8 @@ int sig_nr;			/* signal to be sent */
 	   	rp->p_endpoint, sig_nr);
        }
        sigaddset(&priv(rp)->s_sig_pending, sig_nr);
-       send_sig(rp->p_endpoint, SIGKSIGSM);
+       if(OK != send_sig(rp->p_endpoint, SIGKSIGSM))
+       	panic("send_sig failed");
        return;
   }
 
@@ -434,7 +437,8 @@ int sig_nr;			/* signal to be sent */
       sigaddset(&rp->p_pending, sig_nr);
       if (! (RTS_ISSET(rp, RTS_SIGNALED))) {		/* other pending */
 	  RTS_SET(rp, RTS_SIGNALED | RTS_SIG_PENDING);
-          send_sig(sig_mgr, SIGKSIG);
+          if(OK != send_sig(sig_mgr, SIGKSIG))
+	  	panic("send_sig failed");
       }
   }
 }

kernel/system/do_safemap.c

@@ -163,7 +163,8 @@ int map_invoke_vm(struct proc * caller,
 
 	/* Connect caller on vmrequest wait queue. */
 	if(!(caller->p_vmrequest.nextrequestor = vmrequest))
-		send_sig(VM_PROC_NR, SIGKMEM);
+		if(OK != send_sig(VM_PROC_NR, SIGKMEM))
+			panic("send_sig failed");
 	vmrequest = caller;
 
 	return OK;