block: Add Kconfig help which notes that ext4 needs CONFIG_LBD
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jens Axboe <jens.axboe@oracle.com>
diff --git a/block/Kconfig b/block/Kconfig
index ac0956f..0cbb3b8 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -36,6 +36,12 @@
This option also enables support for single files larger than
2TB.
+ The ext4 filesystem requires that this feature be enabled in
+ order to support filesystems that have the huge_file feature
+ enabled. Otherwise, it will refuse to mount any filesystems
+ that use the huge_file feature, which is enabled by default
+ by mke2fs.ext4. The GFS2 filesystem also requires this feature.
+
If unsure, say N.
config BLK_DEV_IO_TRACE