HWPOISON: Add a madvise() injector for soft page offlining

Process based injection is much easier to handle for test programs, who can first bring a page into a specific state and then test. So add a new MADV_SOFT_OFFLINE to soft offline a page, similar to the existing hard offline injector. Signed-off-by: Andi Kleen <[email protected]>
chewitt · Dec 16, 2009 · afcf938 · afcf938
1 parent facb601
commit afcf938
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Showing 2 changed files with 13 additions and 3 deletions.
diff --git a/include/asm-generic/mman-common.h b/include/asm-generic/mman-common.h
@@ -40,6 +40,7 @@
 #define MADV_DONTFORK	10		/* don't inherit across fork */
 #define MADV_DOFORK	11		/* do inherit across fork */
 #define MADV_HWPOISON	100		/* poison a page for testing */
+#define MADV_SOFT_OFFLINE 101		/* soft offline page for testing */
 
 #define MADV_MERGEABLE   12		/* KSM may merge identical pages */
 #define MADV_UNMERGEABLE 13		/* KSM may not merge identical pages */

diff --git a/mm/madvise.c b/mm/madvise.c
@@ -9,6 +9,7 @@
 #include <linux/pagemap.h>
 #include <linux/syscalls.h>
 #include <linux/mempolicy.h>
+#include <linux/page-isolation.h>
 #include <linux/hugetlb.h>
 #include <linux/sched.h>
 #include <linux/ksm.h>
@@ -222,7 +223,7 @@ static long madvise_remove(struct vm_area_struct *vma,
 /*
  * Error injection support for memory error handling.
  */
-static int madvise_hwpoison(unsigned long start, unsigned long end)
+static int madvise_hwpoison(int bhv, unsigned long start, unsigned long end)
 {
 	int ret = 0;
 
@@ -233,6 +234,14 @@ static int madvise_hwpoison(unsigned long start, unsigned long end)
 		int ret = get_user_pages_fast(start, 1, 0, &p);
 		if (ret != 1)
 			return ret;
+		if (bhv == MADV_SOFT_OFFLINE) {
+			printk(KERN_INFO "Soft offlining page %lx at %lx\n",
+				page_to_pfn(p), start);
+			ret = soft_offline_page(p, MF_COUNT_INCREASED);
+			if (ret)
+				break;
+			continue;
+		}
 		printk(KERN_INFO "Injecting memory failure for page %lx at %lx\n",
 		       page_to_pfn(p), start);
 		/* Ignore return value for now */
@@ -333,8 +342,8 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
 	size_t len;
 
 #ifdef CONFIG_MEMORY_FAILURE
-	if (behavior == MADV_HWPOISON)
-		return madvise_hwpoison(start, start+len_in);
+	if (behavior == MADV_HWPOISON || behavior == MADV_SOFT_OFFLINE)
+		return madvise_hwpoison(behavior, start, start+len_in);
 #endif
 	if (!madvise_behavior_valid(behavior))
 		return error;