In the recent 1.8 snapshots, Mojang made cobblestone generate under gravel paths to prevent it falling into caves. This doesn't fix the problem. I found a village in a world and I saw that the supposed "cobblestone" under the path just generated at the bottom of the cave below the gravel.
Linked issues
Attachments
Comments

Seed is 961751257
Confirmed, and let me just say - THAT is an awesome hole!

Duplicate of MC-45088
Changing to duplicate of MC-1948
Different issue, MC-45088 is the correct duplicate.
Please provide the seed for this world.