[PATCH v1 5/5] fsverity: update the documentation

[Mimi Zohar <zohar@linux.ibm.com>]

Update the fsverity documentation related to IMA signature support.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
---
 Documentation/filesystems/fsverity.rst | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/Documentation/filesystems/fsverity.rst b/Documentation/filesystems/fsverity.rst
index 1d831e3cbcb3..c71f6e365df5 100644
--- a/Documentation/filesystems/fsverity.rst
+++ b/Documentation/filesystems/fsverity.rst
@@ -74,8 +74,12 @@ authenticating the files is up to userspace.  However, to meet some
 users' needs, fs-verity optionally supports a simple signature
 verification mechanism where users can configure the kernel to require
 that all fs-verity files be signed by a key loaded into a keyring; see
-`Built-in signature verification`_.  Support for fs-verity file hashes
-in IMA (Integrity Measurement Architecture) policies is also planned.
+`Built-in signature verification`_.
+
+IMA (Integrity Measurement Architecture) supports fs-verity file
+digests based signatures stored as security.ima xattrs, which are
+identified by the signature type IMA_VERITY_DIGSIG.
+
 
 User API
 ========
@@ -653,13 +657,13 @@ weren't already directly answered in other parts of this document.
     hashed and what to do with those hashes, such as log them,
     authenticate them, or add them to a measurement list.
 
-    IMA is planned to support the fs-verity hashing mechanism as an
-    alternative to doing full file hashes, for people who want the
-    performance and security benefits of the Merkle tree based hash.
-    But it doesn't make sense to force all uses of fs-verity to be
-    through IMA.  As a standalone filesystem feature, fs-verity
-    already meets many users' needs, and it's testable like other
-    filesystem features e.g. with xfstests.
+    IMA supports the fs-verity hashing mechanism as an alternative
+    to doing full file hashes, for people who want the performance
+    and security benefits of the Merkle tree based hash.  But it
+    doesn't make sense to force all uses of fs-verity to be through
+    IMA.  As a standalone filesystem feature, fs-verity already meets
+    many users' needs, and it's testable like other filesystem
+    features e.g. with xfstests.
 
 :Q: Isn't fs-verity useless because the attacker can just modify the
     hashes in the Merkle tree, which is stored on-disk?
-- 
2.27.0