svn commit: r260204 - head/sys/amd64/amd64

[Konstantin Belousov]

Author: kib
Date: Thu Jan  2 18:49:05 2014
New Revision: 260204
URL: http://svnweb.freebsd.org/changeset/base/260204

Log:
  Assert that accounting for the pmap resident pages does not underflow.
  
  Reviewed by:	alc
  Sponsored by:	The FreeBSD Foundation
  MFC after:	1 week

Modified:
  head/sys/amd64/amd64/pmap.c

Modified: head/sys/amd64/amd64/pmap.c
==============================================================================
--- head/sys/amd64/amd64/pmap.c	Thu Jan  2 18:30:24 2014	(r260203)
+++ head/sys/amd64/amd64/pmap.c	Thu Jan  2 18:49:05 2014	(r260204)
@@ -608,6 +608,9 @@ pmap_resident_count_dec(pmap_t pmap, int
 {
 
 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
+	KASSERT(pmap->pm_stats.resident_count >= count,
+	    ("pmap %p resident count underflow %ld %d", pmap,
+	    pmap->pm_stats.resident_count, count));
 	pmap->pm_stats.resident_count -= count;
 }