x86/speculation: Add RETPOLINE_AMD support to the inline asm CALL_NOSPEC variant

..so that they match their asm counterpart.

Add the missing ANNOTATE_NOSPEC_ALTERNATIVE in CALL_NOSPEC, while at it.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wang YanQing <udknight@gmail.com>
Cc: dhaval.giani@oracle.com
Cc: srinivas.eeda@oracle.com
Link: http://lkml.kernel.org/r/c3975665-173e-4d70-8dee-06c926ac26ee@default

arch/x86/include/asm/nospec-branch.h

@@ -170,11 +170,15 @@
  */
 # define CALL_NOSPEC						\
 	ANNOTATE_NOSPEC_ALTERNATIVE				\
-	ALTERNATIVE(						\
+	ALTERNATIVE_2(						\
 	ANNOTATE_RETPOLINE_SAFE					\
 	"call *%[thunk_target]\n",				\
 	"call __x86_indirect_thunk_%V[thunk_target]\n",		\
-	X86_FEATURE_RETPOLINE)
+	X86_FEATURE_RETPOLINE,					\
+	"lfence;\n"						\
+	ANNOTATE_RETPOLINE_SAFE					\
+	"call *%[thunk_target]\n",				\
+	X86_FEATURE_RETPOLINE_AMD)
 # define THUNK_TARGET(addr) [thunk_target] "r" (addr)
 
 #elif defined(CONFIG_X86_32) && defined(CONFIG_RETPOLINE)
@@ -184,7 +188,8 @@
  * here, anyway.
  */
 # define CALL_NOSPEC						\
-	ALTERNATIVE(						\
+	ANNOTATE_NOSPEC_ALTERNATIVE				\
+	ALTERNATIVE_2(						\
 	ANNOTATE_RETPOLINE_SAFE					\
 	"call *%[thunk_target]\n",				\
 	"       jmp    904f;\n"					\
@@ -199,7 +204,11 @@
 	"       ret;\n"						\
 	"       .align 16\n"					\
 	"904:	call   901b;\n",				\
-	X86_FEATURE_RETPOLINE)
+	X86_FEATURE_RETPOLINE,					\
+	"lfence;\n"						\
+	ANNOTATE_RETPOLINE_SAFE					\
+	"call *%[thunk_target]\n",				\
+	X86_FEATURE_RETPOLINE_AMD)
 
 # define THUNK_TARGET(addr) [thunk_target] "rm" (addr)
 #else /* No retpoline for C / inline asm */