vfs: Add some logging to the core users of the fs_context log

Add some logging to the core users of the fs_context log so that
information can be extracted from them as to the reason for failure.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2 files changed, 4 insertions, 2 deletions

diff --git a/fs/super.c b/fs/super.c
index 0ebb5c11fa56..583a0124bc39 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1467,8 +1467,10 @@ int vfs_get_tree(struct fs_context *fc)
         struct super_block *sb;
         int error;
 
-        if (fc->fs_type->fs_flags & FS_REQUIRES_DEV && !fc->source)
+        if (fc->fs_type->fs_flags & FS_REQUIRES_DEV && !fc->source) {
+                errorf(fc, "Filesystem requires source device");
                 return -ENOENT;
+        }
 
         if (fc->root)
                 return -EBUSY;
diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c
index 571ef3447426..c126b34fd4ff 100644
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -17,7 +17,7 @@
 
 #include <trace/events/cgroup.h>
 
-#define cg_invalf(fc, fmt, ...) ({ pr_err(fmt, ## __VA_ARGS__); -EINVAL; })
+#define cg_invalf(fc, fmt, ...) invalf(fc, fmt, ## __VA_ARGS__)
 
 /*
  * pidlists linger the following amount before being destroyed.  The goal