docs: add note about NVMe-multipath to TODO

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/Documentation/TODO b/Documentation/TODO
index 7b61ce72acbeb2726c25beaaa3b337a3aecd3436..6dc1c4fcf08c8cd80bb134bf0cf73d9e1428b55f 100644 (file)
--- a/Documentation/TODO
+++ b/Documentation/TODO
@@ -1,6 +1,24 @@
 
  Note that items with (!) have high priority.
 
+lsblk
+-----
+   The problem is NVMe-multipath driver where in /sys/.../slaves/ are nodes
+   that should be probably hidden for userspace. Note that kernel developers
+   promised to fix this issue in kernel *** so hold off from that for now***
+   [Mar 1, 2018].
+
+   Anyway, possible userspace solution is:
+
+   - verify that slave/holder nodes points to the real block devices
+     (/sys/dev/block/<maj:min> for the node exists), otherwise silently ignore
+     the slave/holder node -- see set_cxt().
+
+   - the same verification we necessary for nodes in /sys/block/<name>. It means
+     verify result from sysfs_devname_to_devno() in set_cxt().
+
+
+
 cleanup lib/path.c: [Karel Zak for v2.33]
 ------------------
    - always return rc from all functions