If you do 'echo 0 0 > /proc/sys/vm/lowmem_reserve_ratio' the kernel gets a
divide-by-zero.
Prevent that, and fiddle with some whitespace too.
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/mm/page_alloc.c | 21 +++++++++++++++------
1 files changed, 15 insertions(+), 6 deletions(-)
diff -puN mm/page_alloc.c~setup_per_zone_lowmem_reserve-oops-fix mm/page_alloc.c
--- 25/mm/page_alloc.c~setup_per_zone_lowmem_reserve-oops-fix 2005-03-01 00:13:57.000000000 -0800
+++ 25-akpm/mm/page_alloc.c 2005-03-01 00:13:57.000000000 -0800
@@ -37,13 +37,17 @@
#include <asm/tlbflush.h>
#include "internal.h"
-/* MCD - HACK: Find somewhere to initialize this EARLY, or make this initializer cleaner */
+/*
+ * MCD - HACK: Find somewhere to initialize this EARLY, or make this
+ * initializer cleaner
+ */
nodemask_t node_online_map = { { [0] = 1UL } };
nodemask_t node_possible_map = NODE_MASK_ALL;
struct pglist_data *pgdat_list;
unsigned long totalram_pages;
unsigned long totalhigh_pages;
long nr_swap_pages;
+
/*
* results with 256, 32 in the lowmem_reserve sysctl:
* 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
@@ -1924,15 +1928,20 @@ static void setup_per_zone_lowmem_reserv
for_each_pgdat(pgdat) {
for (j = 0; j < MAX_NR_ZONES; j++) {
- struct zone * zone = pgdat->node_zones + j;
+ struct zone *zone = pgdat->node_zones + j;
unsigned long present_pages = zone->present_pages;
zone->lowmem_reserve[j] = 0;
for (idx = j-1; idx >= 0; idx--) {
- struct zone * lower_zone = pgdat->node_zones + idx;
+ struct zone *lower_zone;
+
+ if (sysctl_lowmem_reserve_ratio[idx] < 1)
+ sysctl_lowmem_reserve_ratio[idx] = 1;
- lower_zone->lowmem_reserve[j] = present_pages / sysctl_lowmem_reserve_ratio[idx];
+ lower_zone = pgdat->node_zones + idx;
+ lower_zone->lowmem_reserve[j] = present_pages /
+ sysctl_lowmem_reserve_ratio[idx];
present_pages += lower_zone->present_pages;
}
}
@@ -2039,7 +2048,7 @@ module_init(init_per_zone_pages_min)
* changes.
*/
int min_free_kbytes_sysctl_handler(ctl_table *table, int write,
- struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
+ struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
{
proc_dointvec(table, write, file, buffer, length, ppos);
setup_per_zone_pages_min();
@@ -2056,7 +2065,7 @@ int min_free_kbytes_sysctl_handler(ctl_t
* if in function of the boot time zone sizes.
*/
int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write,
- struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
+ struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
{
proc_dointvec_minmax(table, write, file, buffer, length, ppos);
setup_per_zone_lowmem_reserve();
_