m68k: switch to saner kernel_execve() semantics

Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/m68k/Kconfig

@@ -16,6 +16,7 @@ config M68K
 	select ARCH_WANT_IPC_PARSE_VERSION
 	select ARCH_USES_GETTIMEOFFSET if MMU && !COLDFIRE
 	select GENERIC_KERNEL_THREAD
+	select GENERIC_KERNEL_EXECVE
 	select HAVE_MOD_ARCH_SPECIFIC
 	select MODULES_USE_ELF_REL
 	select MODULES_USE_ELF_RELA

arch/m68k/include/asm/unistd.h

@@ -383,7 +383,6 @@
 #define __ARCH_WANT_SYS_RT_SIGACTION
 #define __ARCH_WANT_SYS_RT_SIGSUSPEND
 #define __ARCH_WANT_SYS_EXECVE
-#define __ARCH_WANT_KERNEL_EXECVE
 
 /*
  * "Conditional" syscalls

arch/m68k/kernel/entry.S

@@ -115,16 +115,9 @@ ENTRY(ret_from_kernel_thread)
 	| a3 contains the kernel thread payload, d7 - its argument
 	movel	%d1,%sp@-
 	jsr	schedule_tail
-	GET_CURRENT(%d0)
 	movel	%d7,(%sp)
 	jsr	%a3@
 	addql	#4,%sp
-	movel	%d0,(%sp)
-	jra	sys_exit
-
-ENTRY(ret_from_kernel_execve)
-	movel	4(%sp), %sp
-	GET_CURRENT(%d0)
 	jra	ret_from_exception
 
 #if defined(CONFIG_COLDFIRE) || !defined(CONFIG_MMU)