init/do_mounts.c: add create_dev() failure log

If create_dev() function fails to create the root mount device (/dev/root), then it goes to panic as root device not found but there is no printk in this case. So I have added the log in case it fails to create the root device. It will help in debugging. [[email protected]: simplify printk(), use pr_emerg(), display errno] Signed-off-by: Vishnu Pratap Singh <[email protected]> Acked-by: Pavel Machek <[email protected]> Cc: Paul Gortmaker <[email protected]> Cc: Mike Snitzer <[email protected]> Cc: Dan Ehrenberg <[email protected]> Cc: Miklos Szeredi <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
kyagi · Jun 26, 2015 · c69e3c3 · c69e3c3
1 parent bffacb9
commit c69e3c3
Showing 1 changed file with 7 additions and 2 deletions.
diff --git a/init/do_mounts.c b/init/do_mounts.c
@@ -533,8 +533,13 @@ void __init mount_root(void)
 	}
 #endif
 #ifdef CONFIG_BLOCK
-	create_dev("/dev/root", ROOT_DEV);
-	mount_block_root("/dev/root", root_mountflags);
+	{
+		int err = create_dev("/dev/root", ROOT_DEV);
+
+		if (err < 0)
+			pr_emerg("Failed to create /dev/root: %d\n", err);
+		mount_block_root("/dev/root", root_mountflags);
+	}
 #endif
 }