PERFORCE change 115881 for review

Oleksandr Tymoshenko gonzo at FreeBSD.org
Wed Mar 14 20:57:01 UTC 2007


http://perforce.freebsd.org/chv.cgi?CH=115881

Change 115881 by gonzo at gonzo_jeeves on 2007/03/14 20:56:39

	o vm_fault_prefault calls pmap_enter with corespondent entry
	    protection, so if we're prefaulting R/W region with COW 
	    all pages except faulting one are mapped with R/W permissions i
	    and therefore fail to perform COW operation. This issue is to
	    be investigated, meanwhile work it around with disabling prefault
	    for MIPS at all.
	o Some spellchecking stuff.	    

Affected files ...

.. //depot/projects/mips2/src/sys/mips/mips/pmap.c#21 edit

Differences ...

==== //depot/projects/mips2/src/sys/mips/mips/pmap.c#21 (text+ko) ====

@@ -1657,18 +1657,17 @@
 /*
  *	pmap_is_prefaultable:
  *
- *	Return whether or not the specified virtual address is elgible
+ *	Return whether or not the specified virtual address is eligible
  *	for prefault.
  */
 boolean_t
 pmap_is_prefaultable(pmap_t pmap, vm_offset_t va)
 {
-	pt_entry_t *pte;
-
-	pte = pmap_pte(pmap, va);
-	if (pte_valid(pte))
-		return (FALSE);
-	return (TRUE);
+	/* 
+	 * XXX: prefault causes bugs with COW, so let's stick
+	 * with all pages not eligible to prefault.
+	 */
+	return (FALSE);
 }
 
 /*


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