[PATCH] docs: sysfs-block: document hidden sysfs entry

[Sagi Grimberg]

/sys/block/<disk>/hidden is undocumented. Document it.

Signed-off-by: Sagi Grimberg <sagi at grimberg.me>
---
 Documentation/ABI/stable/sysfs-block | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/ABI/stable/sysfs-block b/Documentation/ABI/stable/sysfs-block
index ac1e519272aa..282de3680367 100644
--- a/Documentation/ABI/stable/sysfs-block
+++ b/Documentation/ABI/stable/sysfs-block
@@ -705,6 +705,15 @@ Description:
 		zoned will report "none".
 
 
+What:		/sys/block/<disk>/hidden
+Date:		March 2023
+Contact:	linux-block at vger.kernel.org
+Description:
+		[RO] the block device is hidden. it doesn’t produce events, and
+		can’t be opened from userspace or using blkdev_get*.
+		Used for the underlying components of multipath devices.
+
+
 What:		/sys/block/<disk>/stat
 Date:		February 2008
 Contact:	Jerome Marchand <jmarchan at redhat.com>
-- 
2.34.1