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Diffstat (limited to 'arch/x86_64/kernel/e820.c')
-rw-r--r--arch/x86_64/kernel/e820.c26
1 files changed, 18 insertions, 8 deletions
diff --git a/arch/x86_64/kernel/e820.c b/arch/x86_64/kernel/e820.c
index 56516ac92e5d..7c154dfff64a 100644
--- a/arch/x86_64/kernel/e820.c
+++ b/arch/x86_64/kernel/e820.c
@@ -2,6 +2,12 @@
* Handle the memory map.
* The functions here do the job until bootmem takes over.
* $Id: e820.c,v 1.4 2002/09/19 19:25:32 ak Exp $
+ *
+ * Getting sanitize_e820_map() in sync with i386 version by applying change:
+ * - Provisions for empty E820 memory regions (reported by certain BIOSes).
+ * Alex Achenbach <xela@slit.de>, December 2002.
+ * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
+ *
*/
#include <linux/config.h>
#include <linux/kernel.h>
@@ -277,7 +283,7 @@ static int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map)
int chgidx, still_changing;
int overlap_entries;
int new_bios_entry;
- int old_nr, new_nr;
+ int old_nr, new_nr, chg_nr;
int i;
/*
@@ -331,20 +337,24 @@ static int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map)
for (i=0; i < 2*old_nr; i++)
change_point[i] = &change_point_list[i];
- /* record all known change-points (starting and ending addresses) */
+ /* record all known change-points (starting and ending addresses),
+ omitting those that are for empty memory regions */
chgidx = 0;
for (i=0; i < old_nr; i++) {
- change_point[chgidx]->addr = biosmap[i].addr;
- change_point[chgidx++]->pbios = &biosmap[i];
- change_point[chgidx]->addr = biosmap[i].addr + biosmap[i].size;
- change_point[chgidx++]->pbios = &biosmap[i];
+ if (biosmap[i].size != 0) {
+ change_point[chgidx]->addr = biosmap[i].addr;
+ change_point[chgidx++]->pbios = &biosmap[i];
+ change_point[chgidx]->addr = biosmap[i].addr + biosmap[i].size;
+ change_point[chgidx++]->pbios = &biosmap[i];
+ }
}
+ chg_nr = chgidx;
/* sort change-point list by memory addresses (low -> high) */
still_changing = 1;
while (still_changing) {
still_changing = 0;
- for (i=1; i < 2*old_nr; i++) {
+ for (i=1; i < chg_nr; i++) {
/* if <current_addr> > <last_addr>, swap */
/* or, if current=<start_addr> & last=<end_addr>, swap */
if ((change_point[i]->addr < change_point[i-1]->addr) ||
@@ -367,7 +377,7 @@ static int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map)
last_type = 0; /* start with undefined memory type */
last_addr = 0; /* start with 0 as last starting address */
/* loop through change-points, determining affect on the new bios map */
- for (chgidx=0; chgidx < 2*old_nr; chgidx++)
+ for (chgidx=0; chgidx < chg_nr; chgidx++)
{
/* keep track of all overlapping bios entries */
if (change_point[chgidx]->addr == change_point[chgidx]->pbios->addr)