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Subject: [PATCH 28/38] vfs: Add some logging to the core users of the
 fs_context log [ver #10]
From:   David Howells <dhowells@redhat.com>
To:     viro@zeniv.linux.org.uk
Cc:     torvalds@linux-foundation.org, dhowells@redhat.com,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Fri, 27 Jul 2018 18:34:29 +0100
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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>
---

 fs/super.c                |    4 +++-
 kernel/cgroup/cgroup-v1.c |    2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/super.c b/fs/super.c
index bbef5a5057c0..3fe5d12b7697 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1735,8 +1735,10 @@ int vfs_get_tree(struct fs_context *fc)
 	struct super_block *sb;
 	int ret;
 
-	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 4238a89ca721..fb721aa20aa0 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