[PATCH] memory hotadd fixes: find_next_system_ram catch range fix

find_next_system_ram() is used to find available memory resource at onlining newly added memory. This patch fixes following problem. find_next_system_ram() cannot catch this case. Resource: (start)-------------(end) Section : (start)-------------(end) Signed-off-by: KAMEZAWA Hiroyuki <[email protected]> Cc: Keith Mannthey <[email protected]> Cc: Yasunori Goto <[email protected]> Cc: Dave Hansen <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
mrcsosa · Aug 6, 2006 · 58c1b5b · 58c1b5b
1 parent 0f04ab5
commit 58c1b5b
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Showing 2 changed files with 3 additions and 2 deletions.
diff --git a/kernel/resource.c b/kernel/resource.c
@@ -244,6 +244,7 @@ int find_next_system_ram(struct resource *res)
 
 	start = res->start;
 	end = res->end;
+	BUG_ON(start >= end);
 
 	read_lock(&resource_lock);
 	for (p = iomem_resource.child; p ; p = p->sibling) {
@@ -254,7 +255,7 @@ int find_next_system_ram(struct resource *res)
 			p = NULL;
 			break;
 		}
-		if (p->start >= start)
+		if ((p->end >= start) && (p->start < end))
 			break;
 	}
 	read_unlock(&resource_lock);

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
@@ -163,7 +163,7 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
 	res.flags = IORESOURCE_MEM; /* we just need system ram */
 	section_end = res.end;
 
-	while (find_next_system_ram(&res) >= 0) {
+	while ((res.start < res.end) && (find_next_system_ram(&res) >= 0)) {
 		start_pfn = (unsigned long)(res.start >> PAGE_SHIFT);
 		nr_pages = (unsigned long)
                            ((res.end + 1 - res.start) >> PAGE_SHIFT);