pstore/ram: Move initialization earlier

Since only one single ramoops area allowed at a time, other probes
(like device tree) are meaningless, as it will waste CPU resources.
So let's check for being already initialized first.
Signed-off-by: Yue Hu <huyue2@yulong.com>
Signed-off-by: Kees Cook <keescook@chromium.org>

fs/pstore/ram.c

@@ -717,15 +717,6 @@ static int ramoops_probe(struct platform_device *pdev)
 	phys_addr_t paddr;
 	int err = -EINVAL;
 
-	if (dev_of_node(dev) && !pdata) {
-		pdata = &pdata_local;
-		memset(pdata, 0, sizeof(*pdata));
-
-		err = ramoops_parse_dt(pdev, pdata);
-		if (err < 0)
-			goto fail_out;
-	}
-
 	/*
 	 * Only a single ramoops area allowed at a time, so fail extra
 	 * probes.
@@ -735,6 +726,15 @@ static int ramoops_probe(struct platform_device *pdev)
 		goto fail_out;
 	}
 
+	if (dev_of_node(dev) && !pdata) {
+		pdata = &pdata_local;
+		memset(pdata, 0, sizeof(*pdata));
+
+		err = ramoops_parse_dt(pdev, pdata);
+		if (err < 0)
+			goto fail_out;
+	}
+
 	/* Make sure we didn't get bogus platform data pointer. */
 	if (!pdata) {
 		pr_err("NULL platform data\n");