diff --git a/Documentation/pretty-formats.txt b/Documentation/pretty-formats.txt
index e3d8a83b23..d9eddedc72 100644
--- a/Documentation/pretty-formats.txt
+++ b/Documentation/pretty-formats.txt
@@ -130,6 +130,9 @@ The placeholders are:
 - '%b': body
 - '%B': raw body (unwrapped subject and body)
 - '%N': commit notes
+- '%GG': raw verification message from GPG for a signed commit
+- '%G?': show either "G" for Good or "B" for Bad for a signed commit
+- '%GS': show the name of the signer for a signed commit
 - '%gD': reflog selector, e.g., `refs/stash@{1}`
 - '%gd': shortened reflog selector, e.g., `stash@{1}`
 - '%gn': reflog identity name
diff --git a/Documentation/pretty-options.txt b/Documentation/pretty-options.txt
index 2a3dc8664f..5e499421a4 100644
--- a/Documentation/pretty-options.txt
+++ b/Documentation/pretty-options.txt
@@ -66,3 +66,7 @@ being displayed. Examples: "--notes=foo" will show only notes from
 --[no-]standard-notes::
 	These options are deprecated. Use the above --notes/--no-notes
 	options instead.
+
+--show-signature::
+	Check the validity of a signed commit object by passing the signature
+	to `gpg --verify` and show the output.
diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index be800e09bd..c48cd19f12 100644
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -225,6 +225,13 @@ _get_comp_words_by_ref ()
 fi
 fi
 
+# Quotes the argument for shell reuse
+__git_quote()
+{
+	local quoted=${1//\'/\'\\\'\'}
+	printf "'%s'" "$quoted"
+}
+
 # Generates completion reply with compgen, appending a space to possible
 # completion words, if necessary.
 # It accepts 1 to 4 arguments:
@@ -261,7 +268,7 @@ __gitcomp ()
 __gitcomp_nl ()
 {
 	local IFS=$'\n'
-	COMPREPLY=($(compgen -P "${2-}" -S "${4- }" -W "$1" -- "${3-$cur}"))
+	COMPREPLY=($(compgen -P "${2-}" -S "${4- }" -W "$(__git_quote "$1")" -- "${3-$cur}"))
 }
 
 __git_heads ()