Merge tag 'x86_vdso_for_v5.19_rc1' of git://git.kernel.org/pub/scm/li…

…nux/kernel/git/tip/tip

Pull x86 vdso update from Borislav Petkov:

 - Get rid of CONFIG_LEGACY_VSYSCALL_EMULATE as nothing should be using
   it anymore

* tag 'x86_vdso_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/vsyscall: Remove CONFIG_LEGACY_VSYSCALL_EMULATE

arch/x86/Kconfig

@@ -2330,28 +2330,16 @@ choice
 	  it can be used to assist security vulnerability exploitation.
 
 	  This setting can be changed at boot time via the kernel command
-	  line parameter vsyscall=[emulate|xonly|none].
+	  line parameter vsyscall=[emulate|xonly|none].  Emulate mode
+	  is deprecated and can only be enabled using the kernel command
+	  line.
 
 	  On a system with recent enough glibc (2.14 or newer) and no
 	  static binaries, you can say None without a performance penalty
 	  to improve security.
 
 	  If unsure, select "Emulate execution only".
 
-	config LEGACY_VSYSCALL_EMULATE
-		bool "Full emulation"
-		help
-		  The kernel traps and emulates calls into the fixed vsyscall
-		  address mapping. This makes the mapping non-executable, but
-		  it still contains readable known contents, which could be
-		  used in certain rare security vulnerability exploits. This
-		  configuration is recommended when using legacy userspace
-		  that still uses vsyscalls along with legacy binary
-		  instrumentation tools that require code to be readable.
-
-		  An example of this type of legacy userspace is running
-		  Pin on an old binary that still uses vsyscalls.
-
 	config LEGACY_VSYSCALL_XONLY
 		bool "Emulate execution only"
 		help

arch/x86/entry/vsyscall/vsyscall_64.c

@@ -48,7 +48,7 @@ static enum { EMULATE, XONLY, NONE } vsyscall_mode __ro_after_init =
 #elif defined(CONFIG_LEGACY_VSYSCALL_XONLY)
 	XONLY;
 #else
-	EMULATE;
+	#error VSYSCALL config is broken
 #endif
 
 static int __init vsyscall_setup(char *str)