From: Ben Gras <ben@minix3.org>
Date: Thu, 20 Oct 2005 20:59:02 +0000 (+0000)
Subject:  . check for notify() from NONE (shouldn't happen any more)
X-Git-Tag: v3.1.2a~583
X-Git-Url: http://zhaoyanbai.com/repos/?a=commitdiff_plain;h=cf16c73e62caedf95715dbba616500865498732c;p=minix.git

 . check for notify() from NONE (shouldn't happen any more)
 . test for cleared process slots when checking processes on exiting
 . clear process slot first, then do cleanup on exiting
---

diff --git a/kernel/proc.c b/kernel/proc.c
index ec92b52d2..125c34363 100755
--- a/kernel/proc.c
+++ b/kernel/proc.c
@@ -349,6 +349,11 @@ unsigned flags;				/* system call flags */
             src_id = (chunk - &map->chunk[0]) * BITCHUNK_BITS + i;
             if (src_id >= NR_SYS_PROCS) break;		/* out of range */
             src_proc_nr = id_to_nr(src_id);		/* get source proc */
+#if DEBUG_ENABLE_IPC_WARNINGS
+	    if(src_proc_nr == NONE) {
+		kprintf("mini_receive: sending notify from NONE\n");
+	    }
+#endif
             if (src!=ANY && src!=src_proc_nr) continue;	/* source not ok */
             *chunk &= ~(1 << i);			/* no longer pending */
 
diff --git a/kernel/system/do_exit.c b/kernel/system/do_exit.c
index fd6b6fc0b..f6a28d060 100644
--- a/kernel/system/do_exit.c
+++ b/kernel/system/do_exit.c
@@ -49,6 +49,11 @@ register struct proc *rc;		/* slot of process to clean up */
   register struct proc *rp;		/* iterate over process table */
   register struct proc **xpp;		/* iterate over caller queue */
   int i;
+  int sys_id;
+  char rts_flags;
+
+  /* Don't clear if already cleared. */
+  if(isemptyp(rc)) return;
 
   /* Turn off any alarm timers at the clock. */   
   reset_timer(&priv(rc)->s_alarm_timer);
@@ -56,11 +61,20 @@ register struct proc *rc;		/* slot of process to clean up */
   /* Make sure that the exiting process is no longer scheduled. */
   if (rc->p_rts_flags == 0) lock_dequeue(rc);
 
+  /* Release the process table slot. If this is a system process, also
+   * release its privilege structure.  Further cleanup is not needed at
+   * this point. All important fields are reinitialized when the 
+   * slots are assigned to another, new process. 
+   */
+  rts_flags = rc->p_rts_flags;
+  rc->p_rts_flags = SLOT_FREE;		
+  if (priv(rc)->s_flags & SYS_PROC) priv(rc)->s_proc_nr = NONE;
+
   /* If the process being terminated happens to be queued trying to send a
    * message (e.g., the process was killed by a signal, rather than it doing 
    * a normal exit), then it must be removed from the message queues.
    */
-  if (rc->p_rts_flags & SENDING) {
+  if (rts_flags & SENDING) {
       xpp = &proc[rc->p_sendto].p_caller_q;	/* destination's queue */
       while (*xpp != NIL_PROC) {		/* check entire queue */
           if (*xpp == rc) {			/* process is on the queue */
@@ -80,6 +94,8 @@ register struct proc *rc;		/* slot of process to clean up */
    * Check all processes. 
    */
   for (rp = BEG_PROC_ADDR; rp < END_PROC_ADDR; rp++) {
+      if(isemptyp(rp))
+	continue;
 
       /* Unset pending notification bits. */
       unset_sys_bit(priv(rp)->s_notify_pending, priv(rc)->s_id);
@@ -114,14 +130,6 @@ register struct proc *rc;		/* slot of process to clean up */
   /* Clean up virtual memory */
   if (rc->p_misc_flags & MF_VM)
   	vm_map_default(rc);
-
-  /* Now it is safe to release the process table slot. If this is a system 
-   * process, also release its privilege structure.  Further cleanup is not
-   * needed at this point. All important fields are reinitialized when the 
-   * slots are assigned to another, new process. 
-   */
-  rc->p_rts_flags = SLOT_FREE;		
-  if (priv(rc)->s_flags & SYS_PROC) priv(rc)->s_proc_nr = NONE;
 }
 
 #endif /* USE_EXIT */