[PATCH v8 6/6] x86/vdso: Enable sframe generation in VDSO

@@ -479,6 +479,13 @@ config HAVE_HARDLOCKUP_DETECTOR_ARCH
 	  It uses the same command line parameters, and sysctl interface,
 	  as the generic hardlockup detectors.
 
+config AS_SFRAME
+	bool
+
+config AS_SFRAME3
+	def_bool $(as-instr,.cfi_startproc\n.cfi_endproc,-Wa$(comma)--gsframe-3)
+	select AS_SFRAME
+
 config UNWIND_USER
 	bool
 

@@ -60,6 +60,13 @@ SECTIONS
 		*(.eh_frame.*)
 	}					:text
 
+#ifdef KEEP_SFRAME
+	.sframe		: {
+		KEEP (*(.sframe))
+		*(.sframe.*)
+	}					:text	:sframe
+#endif
+
 	/*
 	 * Text is well-separated from actual data: there's plenty of
 	 * stuff that isn't used at runtime in between.

@@ -80,6 +87,10 @@ SECTIONS
 		*(.discard)
 		*(.discard.*)
 		*(__bug_table)
+#ifndef KEEP_SFRAME
+		*(.sframe)
+		*(.sframe.*)
+#endif
 	}
 }
 

@@ -89,6 +100,7 @@ SECTIONS
 #define PT_GNU_EH_FRAME	0x6474e550
 #define PT_GNU_STACK	0x6474e551
 #define PT_GNU_PROPERTY	0x6474e553
+#define PT_GNU_SFRAME	0x6474e554
 
 /*
  * We must supply the ELF program headers explicitly to get just one

@@ -104,6 +116,9 @@ PHDRS
 	dynamic		PT_DYNAMIC	PF_R;
 	note		PT_NOTE		PF_R;
 	eh_frame_hdr	PT_GNU_EH_FRAME PF_R;
+#ifdef KEEP_SFRAME
+	sframe		PT_GNU_SFRAME	PF_R;
+#endif
 	gnu_stack	PT_GNU_STACK	PF_RW;
 	gnu_property	PT_GNU_PROPERTY	PF_R;
 }

@@ -14,6 +14,7 @@ vobjs-$(CONFIG_X86_SGX)		+= vsgx.o
 
 # Compilation flags
 flags-y				:= -DBUILD_VDSO64 -m64 -mcmodel=small
+flags-$(CONFIG_AS_SFRAME3)	+= -Wa,--gsframe-3
 
 # The location of this include matters!
 include $(src)/../common/Makefile.include

@@ -9,6 +9,10 @@
 
 #define BUILD_VDSO64
 
+#ifdef CONFIG_AS_SFRAME
+# define KEEP_SFRAME
+#endif
+
 #include "common/vdso-layout.lds.S"
 
 /*