diff -r 1356affa5e44 make/launcher/Launcher-java.base.gmk

--- openjdk/make/launcher/Launcher-java.base.gmk      Wed Nov 25 08:27:15 2020 +0100

+++ openjdk/make/launcher/Launcher-java.base.gmk      Tue Dec 01 12:29:30 2020 +0100

@@ -41,6 +41,16 @@

     OPTIMIZATION := HIGH, \

 ))

+#Wno-error=cpp is present to allow commented warning in ifdef part of main.c

+$(eval $(call SetupBuildLauncher, alt-java, \

+    CFLAGS := -DEXPAND_CLASSPATH_WILDCARDS -DENABLE_ARG_FILES -DREDHAT_ALT_JAVA -Wno-error=cpp, \

+    LDFLAGS_solaris := -R$(OPENWIN_HOME)/lib$(OPENJDK_TARGET_CPU_ISADIR), \

+    LIBS_windows := user32.lib comctl32.lib, \

+    EXTRA_RC_FLAGS := $(JAVA_RC_FLAGS), \

+    VERSION_INFO_RESOURCE := $(JAVA_VERSION_INFO_RESOURCE), \

+    OPTIMIZATION := HIGH, \

+))

+

 ifeq ($(OPENJDK_TARGET_OS), windows)

   $(eval $(call SetupBuildLauncher, javaw, \

       CFLAGS := -DJAVAW -DEXPAND_CLASSPATH_WILDCARDS -DENABLE_ARG_FILES, \

diff -r 25e94aa812b2 src/share/bin/alt_main.h

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000

+++ openjdk/src/java.base/share/native/launcher/alt_main.h	Tue Jun 02 17:15:28 2020 +0100

@@ -0,0 +1,73 @@

+/*

+ * Copyright (c) 2019, Red Hat, Inc. All rights reserved.

+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

+ *

+ * This code is free software; you can redistribute it and/or modify it

+ * under the terms of the GNU General Public License version 2 only, as

+ * published by the Free Software Foundation.  Oracle designates this

+ * particular file as subject to the "Classpath" exception as provided

+ * by Oracle in the LICENSE file that accompanied this code.

+ *

+ * This code is distributed in the hope that it will be useful, but WITHOUT

+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

+ * version 2 for more details (a copy is included in the LICENSE file that

+ * accompanied this code).

+ *

+ * You should have received a copy of the GNU General Public License version

+ * 2 along with this work; if not, write to the Free Software Foundation,

+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

+ *

+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

+ * or visit www.oracle.com if you need additional information or have any

+ * questions.

+ */

+

+#ifdef REDHAT_ALT_JAVA

+

+#include <sys/prctl.h>

+

+

+/* Per task speculation control */

+#ifndef PR_GET_SPECULATION_CTRL

+# define PR_GET_SPECULATION_CTRL    52

+#endif

+#ifndef PR_SET_SPECULATION_CTRL

+# define PR_SET_SPECULATION_CTRL    53

+#endif

+/* Speculation control variants */

+#ifndef PR_SPEC_STORE_BYPASS

+# define PR_SPEC_STORE_BYPASS          0

+#endif

+/* Return and control values for PR_SET/GET_SPECULATION_CTRL */

+

+#ifndef PR_SPEC_NOT_AFFECTED

+# define PR_SPEC_NOT_AFFECTED          0

+#endif

+#ifndef PR_SPEC_PRCTL

+# define PR_SPEC_PRCTL                 (1UL << 0)

+#endif

+#ifndef PR_SPEC_ENABLE

+# define PR_SPEC_ENABLE                (1UL << 1)

+#endif

+#ifndef PR_SPEC_DISABLE

+# define PR_SPEC_DISABLE               (1UL << 2)

+#endif

+#ifndef PR_SPEC_FORCE_DISABLE

+# define PR_SPEC_FORCE_DISABLE         (1UL << 3)

+#endif

+#ifndef PR_SPEC_DISABLE_NOEXEC

+# define PR_SPEC_DISABLE_NOEXEC        (1UL << 4)

+#endif

+

+static void set_speculation() __attribute__((constructor));

+static void set_speculation() {

+  if ( prctl(PR_SET_SPECULATION_CTRL,

+             PR_SPEC_STORE_BYPASS,

+             PR_SPEC_DISABLE_NOEXEC, 0, 0) == 0 ) {

+    return;

+  }

+  prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_STORE_BYPASS, PR_SPEC_DISABLE, 0, 0);

+}

+

+#endif // REDHAT_ALT_JAVA

diff -r 25e94aa812b2 src/share/bin/main.c

--- openjdk/src/java.base/share/native/launcher/main.c	Wed Feb 05 12:20:36 2020 -0300

+++ openjdk/src/java.base/share/native/launcher/main.c	Tue Jun 02 17:15:28 2020 +0100

@@ -34,6 +34,14 @@

 #include "jli_util.h"

 #include "jni.h"

+#ifdef REDHAT_ALT_JAVA

+#if defined(__linux__) && defined(__x86_64__)

+#include "alt_main.h"

+#else

+#warning alt-java requested but SSB mitigation not available on this platform.

+#endif

+#endif

+

 #ifdef _MSC_VER

 #if _MSC_VER > 1400 && _MSC_VER < 1600