--- zzzz-none-000/linux-3.10.107/mm/hwpoison-inject.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/mm/hwpoison-inject.c	2021-02-04 17:41:59.000000000 +0000
@@ -20,8 +20,6 @@
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
-	if (!hwpoison_filter_enable)
-		goto inject;
 	if (!pfn_valid(pfn))
 		return -ENXIO;
 
@@ -30,32 +28,35 @@
 	/*
 	 * This implies unable to support free buddy pages.
 	 */
-	if (!get_page_unless_zero(hpage))
+	if (!get_hwpoison_page(p))
 		return 0;
 
-	if (!PageLRU(p) && !PageHuge(p))
-		shake_page(p, 0);
+	if (!hwpoison_filter_enable)
+		goto inject;
+
+	if (!PageLRU(hpage) && !PageHuge(p))
+		shake_page(hpage, 0);
 	/*
 	 * This implies unable to support non-LRU pages.
 	 */
-	if (!PageLRU(p) && !PageHuge(p))
-		return 0;
+	if (!PageLRU(hpage) && !PageHuge(p))
+		goto put_out;
 
 	/*
 	 * do a racy check with elevated page count, to make sure PG_hwpoison
 	 * will only be set for the targeted owner (or on a free page).
-	 * We temporarily take page lock for try_get_mem_cgroup_from_page().
 	 * memory_failure() will redo the check reliably inside page lock.
 	 */
-	lock_page(hpage);
 	err = hwpoison_filter(hpage);
-	unlock_page(hpage);
 	if (err)
-		return 0;
+		goto put_out;
 
 inject:
-	printk(KERN_INFO "Injecting memory failure at pfn %lx\n", pfn);
+	pr_info("Injecting memory failure at pfn %#lx\n", pfn);
 	return memory_failure(pfn, 18, MF_COUNT_INCREASED);
+put_out:
+	put_hwpoison_page(p);
+	return 0;
 }
 
 static int hwpoison_unpoison(void *data, u64 val)
@@ -71,8 +72,7 @@
 
 static void pfn_inject_exit(void)
 {
-	if (hwpoison_dir)
-		debugfs_remove_recursive(hwpoison_dir);
+	debugfs_remove_recursive(hwpoison_dir);
 }
 
 static int pfn_inject_init(void)
@@ -88,12 +88,12 @@
 	 * hardware status change, hence do not require hardware support.
 	 * They are mainly for testing hwpoison in software level.
 	 */
-	dentry = debugfs_create_file("corrupt-pfn", 0600, hwpoison_dir,
+	dentry = debugfs_create_file("corrupt-pfn", 0200, hwpoison_dir,
 					  NULL, &hwpoison_fops);
 	if (!dentry)
 		goto fail;
 
-	dentry = debugfs_create_file("unpoison-pfn", 0600, hwpoison_dir,
+	dentry = debugfs_create_file("unpoison-pfn", 0200, hwpoison_dir,
 				     NULL, &unpoison_fops);
 	if (!dentry)
 		goto fail;
@@ -123,7 +123,7 @@
 	if (!dentry)
 		goto fail;
 
-#ifdef CONFIG_MEMCG_SWAP
+#ifdef CONFIG_MEMCG
 	dentry = debugfs_create_u64("corrupt-filter-memcg", 0600,
 				    hwpoison_dir, &hwpoison_filter_memcg);
 	if (!dentry)