git: error: gpg failed to sign the data

If you try to sign commit with git, and you get the following error:

====================== 

error: gpg failed to sign the data

fatal: failed to write commit object

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1. Check your ~/.gitconfig file, which must include at least the following sections:

   [user]
           name = Your Name Here
           email = your@email.com
           #key ID coming from gpg --list-keys
           signingkey = AABBCCDDFF112233445566
   [commit]
           gpgsign = 1
   [gpg]
           #could be gpg or gpg2 or full path to them
           program = gpg2 

2. If above is fine, check if your GPG is working correctly on the following link:

 gpg or gpg2 gpg: signing failed: Inappropriate ioctl for device