klp-build: Suppress excessive fuzz output by default

When a patch applies with fuzz, the detailed output from the patch tool
can be very noisy, especially for big patches.

Suppress the fuzz details by default, while keeping the "applied with
fuzz" warning.  The noise can be restored with '--verbose'.

Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>

scripts/livepatch/klp-build

@@ -19,12 +19,11 @@ set -o nounset
 # This helps keep execution in pipes so pipefail+ERR trap can catch errors.
 shopt -s lastpipe
 
-unset DEBUG_CLONE DIFF_CHECKSUM SKIP_CLEANUP XTRACE
+unset DEBUG_CLONE DIFF_CHECKSUM SKIP_CLEANUP VERBOSE XTRACE
 
 REPLACE=1
 SHORT_CIRCUIT=0
 JOBS="$(getconf _NPROCESSORS_ONLN)"
-VERBOSE="-s"
 shopt -o xtrace | grep -q 'on' && XTRACE=1
 
 # Avoid removing the previous $TMP_DIR until args have been fully processed.
@@ -194,7 +193,7 @@ process_args() {
 				shift
 				;;
 			-v | --verbose)
-				VERBOSE="V=1"
+				VERBOSE=1
 				shift
 				;;
 			-d | --debug)
@@ -381,7 +380,7 @@ apply_patch() {
 		echo "$output" >&2
 		die "$patch did not apply"
 	elif [[ "$output" =~ $drift_regex ]]; then
-		echo "$output" >&2
+		[[ -v VERBOSE ]] && echo "$output" >&2
 		warn "${patch} applied with fuzz"
 	fi
 
@@ -544,7 +543,11 @@ build_kernel() {
 	#
 	cmd+=("KBUILD_MODPOST_WARN=1")
 
-	cmd+=("$VERBOSE")
+	if [[ -v VERBOSE ]]; then
+		cmd+=("V=1")
+	else
+		cmd+=("-s")
+	fi
 	cmd+=("-j$JOBS")
 	cmd+=("KCFLAGS=-ffunction-sections -fdata-sections")
 	cmd+=("OBJTOOL_ARGS=${objtool_args[*]}")
@@ -805,7 +808,11 @@ build_patch_module() {
 	[[ $REPLACE -eq 0 ]] && cflags+=("-DKLP_NO_REPLACE")
 
 	cmd=("make")
-	cmd+=("$VERBOSE")
+	if [[ -v VERBOSE ]]; then
+		cmd+=("V=1")
+	else
+		cmd+=("-s")
+	fi
 	cmd+=("-j$JOBS")
 	cmd+=("--directory=.")
 	cmd+=("M=$KMOD_DIR")