Index: openjdk/common/autoconf/build-aux/autoconf-config.sub
===================================================================
--- openjdk/common/autoconf/build-aux/autoconf-config.sub.orig
+++ openjdk/common/autoconf/build-aux/autoconf-config.sub
@@ -302,6 +302,7 @@ case $basic_machine in
 	| pdp10 | pdp11 | pj | pjl \
 	| powerpc | powerpc64 | powerpc64le | powerpcle | ppcbe \
 	| pyramid \
+	| riscv32 | riscv64 \
 	| score \
 	| sh | sh[1234] | sh[24]a | sh[23]e | sh[34]eb | sheb | shbe | shle | sh[1234]le | sh3ele \
 	| sh64 | sh64le \
@@ -383,6 +384,7 @@ case $basic_machine in
 	| pdp10-* | pdp11-* | pj-* | pjl-* | pn-* | power-* \
 	| powerpc-* | powerpc64-* | powerpc64le-* | powerpcle-* | ppcbe-* \
 	| pyramid-* \
+	| riscv32-* | riscv64-* \
 	| romp-* | rs6000-* \
 	| sh-* | sh[1234]-* | sh[24]a-* | sh[23]e-* | sh[34]eb-* | sheb-* | shbe-* \
 	| shle-* | sh[1234]le-* | sh3ele-* | sh64-* | sh64le-* \
Index: openjdk/common/autoconf/platform.m4
===================================================================
--- openjdk/common/autoconf/platform.m4.orig
+++ openjdk/common/autoconf/platform.m4
@@ -96,6 +96,12 @@ AC_DEFUN([PLATFORM_EXTRACT_VARS_FROM_CPU
       VAR_CPU_BITS=64
       VAR_CPU_ENDIAN=big
       ;;
+    riscv64)
+      VAR_CPU=riscv64
+      VAR_CPU_ARCH=riscv
+      VAR_CPU_BITS=64
+      VAR_CPU_ENDIAN=little
+      ;;
     *)
       AC_MSG_ERROR([unsupported cpu $1])
       ;;
@@ -391,6 +397,7 @@ AC_DEFUN([PLATFORM_SETUP_LEGACY_VARS],
     sparc*)  ZERO_ARCHDEF=SPARC ;;
     x86_64*) ZERO_ARCHDEF=AMD64 ;;
     x86)     ZERO_ARCHDEF=IA32  ;;
+    riscv*)  ZERO_ARCHDEF=RISCV  ;;
     *)      ZERO_ARCHDEF=$(echo "${OPENJDK_TARGET_CPU_LEGACY_LIB}" | tr a-z A-Z)
   esac
   AC_SUBST(ZERO_ARCHDEF)
Index: openjdk/hotspot/src/os/linux/vm/os_linux.cpp
===================================================================
--- openjdk/hotspot/src/os/linux/vm/os_linux.cpp.orig
+++ openjdk/hotspot/src/os/linux/vm/os_linux.cpp
@@ -369,7 +369,7 @@ void os::init_system_properties_values()
 //        1: ...
 //        ...
 //        7: The default directories, normally /lib and /usr/lib.
-#if defined(AMD64) || defined(_LP64) && (defined(SPARC) || defined(PPC) || defined(S390))
+#if defined(AMD64) || defined(_LP64) && (defined(SPARC) || defined(PPC) || defined(S390) || defined(RISCV))
 #define DEFAULT_LIBPATH "/usr/lib64:/lib64:/lib:/usr/lib"
 #else
 #define DEFAULT_LIBPATH "/lib:/usr/lib"
@@ -1960,6 +1960,10 @@ void * os::dll_load(const char *filename
   #define EM_AARCH64	183
   #endif
 
+  #ifndef EM_RISCV
+  #define EM_RISCV	243
+  #endif
+
   static const arch_t arch_array[]={
     {EM_386,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
     {EM_486,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
@@ -1982,6 +1986,7 @@ void * os::dll_load(const char *filename
     {EM_PARISC,      EM_PARISC,  ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
     {EM_68K,         EM_68K,     ELFCLASS32, ELFDATA2MSB, (char*)"M68k"},
     {EM_AARCH64,     EM_AARCH64, ELFCLASS64, ELFDATA2LSB, (char*)"AARCH64"},
+    {EM_RISCV,       EM_RISCV,   ELFCLASS64, ELFDATA2LSB, (char*)"RISCV"},
   };
 
   #if  (defined IA32)
@@ -2014,6 +2019,8 @@ void * os::dll_load(const char *filename
     static  Elf32_Half running_arch_code=EM_68K;
   #elif  (defined AARCH64)
     static  Elf32_Half running_arch_code=EM_AARCH64;
+#elif  (defined RISCV)
+    static  Elf32_Half running_arch_code=EM_RISCV;
   #else
     #error Method os::dll_load requires that one of following is defined:\
          IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K, AARCH64