Merge: [s390]: RHEL9.0 - diag288_wdt: do not use stack buffers for hardware data

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/2082

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2171362

Tested: by IBM

Build-Info: https://brewweb.engineering.redhat.com/brew/taskinfo?taskID=50925307



Commits:
fe8973a3 watchdog: diag288_wdt: do not use stack buffers for hardware data
32e40f95 watchdog: diag288_wdt: fix __diag288() inline assembly

Signed-off-by: Tobias Huschle <thuschle@redhat.com>

Approved-by: Steve Best <sbest@redhat.com>
Approved-by: Tony Camuso <tcamuso@redhat.com>

Signed-off-by: Jan Stancek <jstancek@redhat.com>

drivers/watchdog/diag288_wdt.c

@@ -86,7 +86,7 @@ static int __diag288(unsigned int func, unsigned int timeout,
 		"1:\n"
 		EX_TABLE(0b, 1b)
 		: "+d" (err) : "d"(__func), "d"(__timeout),
-		  "d"(__action), "d"(__len) : "1", "cc");
+		  "d"(__action), "d"(__len) : "1", "cc", "memory");
 	return err;
 }
 
@@ -268,12 +268,21 @@ static int __init diag288_init(void)
 	char ebc_begin[] = {
 		194, 197, 199, 201, 213
 	};
+	char *ebc_cmd;
 
 	watchdog_set_nowayout(&wdt_dev, nowayout_info);
 
 	if (MACHINE_IS_VM) {
-		if (__diag288_vm(WDT_FUNC_INIT, 15,
-				 ebc_begin, sizeof(ebc_begin)) != 0) {
+		ebc_cmd = kmalloc(sizeof(ebc_begin), GFP_KERNEL);
+		if (!ebc_cmd) {
+			pr_err("The watchdog cannot be initialized\n");
+			return -ENOMEM;
+		}
+		memcpy(ebc_cmd, ebc_begin, sizeof(ebc_begin));
+		ret = __diag288_vm(WDT_FUNC_INIT, 15,
+				   ebc_cmd, sizeof(ebc_begin));
+		kfree(ebc_cmd);
+		if (ret != 0) {
 			pr_err("The watchdog cannot be initialized\n");
 			return -EINVAL;
 		}