[PATCH] memory hotadd fixes: not-aligned memory hotadd handling fix
ioresouce handling code in memory hotplug allows not-aligned memory hot add.
But when memmap and other memory structures are initialized, parameters should
be aligned. (if not aligned, initialization of mem_map will do wrong, it
assumes parameters are aligned.) This patch fix it.
And this patch allows ioresource collision check to handle -EEXIST.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Keith Mannthey <kmannth@gmail.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 01c9fb9..7d25cc1 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -76,15 +76,22 @@
{
unsigned long i;
int err = 0;
+ int start_sec, end_sec;
+ /* during initialize mem_map, align hot-added range to section */
+ start_sec = pfn_to_section_nr(phys_start_pfn);
+ end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
- for (i = 0; i < nr_pages; i += PAGES_PER_SECTION) {
- err = __add_section(zone, phys_start_pfn + i);
+ for (i = start_sec; i <= end_sec; i++) {
+ err = __add_section(zone, i << PFN_SECTION_SHIFT);
- /* We want to keep adding the rest of the
- * sections if the first ones already exist
+ /*
+ * EEXIST is finally dealed with by ioresource collision
+ * check. see add_memory() => register_memory_resource()
+ * Warning will be printed if there is collision.
*/
if (err && (err != -EEXIST))
break;
+ err = 0;
}
return err;
@@ -213,10 +220,10 @@
}
/* add this memory to iomem resource */
-static void register_memory_resource(u64 start, u64 size)
+static int register_memory_resource(u64 start, u64 size)
{
struct resource *res;
-
+ int ret = 0;
res = kzalloc(sizeof(struct resource), GFP_KERNEL);
BUG_ON(!res);
@@ -228,7 +235,9 @@
printk("System RAM resource %llx - %llx cannot be added\n",
(unsigned long long)res->start, (unsigned long long)res->end);
kfree(res);
+ ret = -EEXIST;
}
+ return ret;
}
@@ -269,7 +278,7 @@
}
/* register this memory as resource */
- register_memory_resource(start, size);
+ ret = register_memory_resource(start, size);
return ret;
error: