torture: Make kvm-recheck.sh report .config errors

Currently, kvm-recheck.sh will print out any .config errors with messages
of the form:

:CONFIG_TASKS_TRACE_RCU=y: improperly set

However, if these are the only errors, the resulting exit code will
declare the run successful.  This commit therefore causes kvm-recheck.sh
to record .config errors in the results directory in a file named
ConfigFragment.diags and also returns a non-zero error code in that case.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

tools/testing/selftests/rcutorture/bin/kvm-recheck.sh

@@ -16,6 +16,8 @@
 T=/tmp/kvm-recheck.sh.$$
 trap 'rm -f $T' 0 2
 
+configerrors=0
+
 PATH=`pwd`/tools/testing/selftests/rcutorture/bin:$PATH; export PATH
 . functions.sh
 for rd in "$@"
@@ -32,7 +34,7 @@ do
 		fi
 		TORTURE_SUITE="`cat $i/../torture_suite`" ; export TORTURE_SUITE
 		configfile=`echo $i | sed -e 's,^.*/,,'`
-		rm -f $i/console.log.*.diags
+		rm -f $i/console.log.*.diags $i/ConfigFragment.diags
 		case "${TORTURE_SUITE}" in
 		X*)
 			;;
@@ -49,8 +51,14 @@ do
 			then
 				echo QEMU killed
 			fi
-			configcheck.sh $i/.config $i/ConfigFragment > $T 2>&1
-			cat $T
+			configcheck.sh $i/.config $i/ConfigFragment > $i/ConfigFragment.diags 2>&1
+			if test -s $i/ConfigFragment.diags
+			then
+				cat $i/ConfigFragment.diags
+				configerrors=$((configerrors+1))
+			else
+				rm $i/ConfigFragment.diags
+			fi
 			if test -r $i/Make.oldconfig.err
 			then
 				cat $i/Make.oldconfig.err
@@ -65,7 +73,14 @@ do
 			if test -f "$i/buildonly"
 			then
 				echo Build-only run, no boot/test
-				configcheck.sh $i/.config $i/ConfigFragment
+				configcheck.sh $i/.config $i/ConfigFragment > $i/ConfigFragment.diags 2>&1
+				if test -s $i/ConfigFragment.diags
+				then
+					cat $i/ConfigFragment.diags
+					configerrors=$((configerrors+1))
+				else
+					rm $i/ConfigFragment.diags
+				fi
 				parse-build.sh $i/Make.out $configfile
 			elif test -f "$i/qemu-cmd"
 			then
@@ -79,10 +94,10 @@ do
 	done
 	if test -f "$rd/kcsan.sum"
 	then
-		if ! test -f $T
+		if ! test -f $i/ConfigFragment.diags
 		then
 			:
-		elif grep -q CONFIG_KCSAN=y $T
+		elif grep -q CONFIG_KCSAN=y $i/ConfigFragment.diags
 		then
 			echo "Compiler or architecture does not support KCSAN!"
 			echo Did you forget to switch your compiler with '--kmake-arg CC=<cc-that-supports-kcsan>'?
@@ -94,17 +109,23 @@ do
 		fi
 	fi
 done
+
+if test "$configerrors" -gt 0
+then
+	echo $configerrors runs with .config errors.
+	ret=1
+fi
 EDITOR=echo kvm-find-errors.sh "${@: -1}" > $T 2>&1
 builderrors="`tr ' ' '\012' < $T | grep -c '/Make.out.diags'`"
 if test "$builderrors" -gt 0
 then
 	echo $builderrors runs with build errors.
-	ret=1
+	ret=2
 fi
 runerrors="`tr ' ' '\012' < $T | grep -c '/console.log.diags'`"
 if test "$runerrors" -gt 0
 then
 	echo $runerrors runs with runtime errors.
-	ret=2
+	ret=3
 fi
 exit $ret