xen: add error handling for xenbus_printf

When xenbus_printf fails, the lack of error-handling code may
cause unexpected results.

This patch adds error-handling code after calling xenbus_printf.

Signed-off-by: Zhouyang Jia <jiazhouyang09@gmail.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
This commit is contained in:
Zhouyang Jia 2018-06-15 07:34:52 +08:00 коммит произвёл Juergen Gross
Родитель 1fe83888a2
Коммит 84c029a733
1 изменённых файлов: 15 добавлений и 3 удалений

Просмотреть файл

@ -289,8 +289,15 @@ static void sysrq_handler(struct xenbus_watch *watch, const char *path,
return;
}
if (sysrq_key != '\0')
xenbus_printf(xbt, "control", "sysrq", "%c", '\0');
if (sysrq_key != '\0') {
err = xenbus_printf(xbt, "control", "sysrq", "%c", '\0');
if (err) {
pr_err("%s: Error %d writing sysrq in control/sysrq\n",
__func__, err);
xenbus_transaction_end(xbt, 1);
return;
}
}
err = xenbus_transaction_end(xbt, 0);
if (err == -EAGAIN)
@ -342,7 +349,12 @@ static int setup_shutdown_watcher(void)
continue;
snprintf(node, FEATURE_PATH_SIZE, "feature-%s",
shutdown_handlers[idx].command);
xenbus_printf(XBT_NIL, "control", node, "%u", 1);
err = xenbus_printf(XBT_NIL, "control", node, "%u", 1);
if (err) {
pr_err("%s: Error %d writing %s\n", __func__,
err, node);
return err;
}
}
return 0;