Fixed corruption of the kmemstatistcs list. The first malloc()

with malloc type at the tail of the list changed the list from
linear to circular.  This seemed to cause surprisingly few problems,
but it now causes weird output from `vmstat -m', probably because
a more important malloc type is now at the tail of the list.

Fix it by abusing ks_limit instead of ks_next as a flag for being
on the list.  Don't forget to clear the flag when a malloc type is
uninit'ed.  Uninit'ing is still fundamentally broken -- it loses
history.

1 files changed, 9 insertions, 5 deletions

diff --git a/sys/kern/kern_malloc.c b/sys/kern/kern_malloc.c
index e7499d5..0b300c2 100644
--- a/sys/kern/kern_malloc.c
+++ b/sys/kern/kern_malloc.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_malloc.c	8.3 (Berkeley) 1/4/94
- * $Id: kern_malloc.c,v 1.54 1999/01/27 21:49:56 dillon Exp $
+ * $Id: kern_malloc.c,v 1.55 1999/05/06 18:12:42 peter Exp $
  */
 
 #include "opt_vm.h"
@@ -138,9 +138,8 @@ malloc(size, type, flags)
 
 	s = splmem();
 
-	if (!type->ks_next) {
+	if (type->ks_limit == 0)
 		malloc_init(type);
-	}
 
 	indx = BUCKETINDX(size);
 	kbp = &bucket[indx];
@@ -283,7 +282,7 @@ free(addr, type)
 #endif
 	register struct malloc_type *ksp = type;
 
-	if (!type->ks_next)
+	if (type->ks_limit == 0)
 		panic("freeing with unknown type (%s)", type->ks_shortdesc);
 
 	KASSERT(kmembase <= (char *)addr && (char *)addr < kmemlimit,
@@ -466,7 +465,7 @@ malloc_init(data)
 	if (type->ks_magic != M_MAGIC) 
 		panic("malloc type lacks magic");
 
-	if (type->ks_next)
+	if (type->ks_limit != 0)
 		return;
 
 	if (cnt.v_page_count == 0)
@@ -494,6 +493,9 @@ malloc_uninit(data)
 	if (cnt.v_page_count == 0)
 		panic("malloc_uninit not allowed before vm init");
 
+	if (type->ks_limit == 0)
+		panic("malloc_uninit on uninitialized type");
+
 	if (type == kmemstatistics)
 		kmemstatistics = type->ks_next;
 	else {
@@ -504,4 +506,6 @@ malloc_uninit(data)
 			}
 		}
 	}
+	type->ks_next = NULL;
+	type->ks_limit = 0;
 }