Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal

Pull pile 2 of execve and kernel_thread unification work from Al Viro:
 "Stuff in there: kernel_thread/kernel_execve/sys_execve conversions for
  several more architectures plus assorted signal fixes and cleanups.

  There'll be more (in particular, real fixes for the alpha
  do_notify_resume() irq mess)..."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (43 commits)
  alpha: don't open-code trace_report_syscall_{enter,exit}
  Uninclude linux/freezer.h
  m32r: trim masks
  avr32: trim masks
  tile: don't bother with SIGTRAP in setup_frame
  microblaze: don't bother with SIGTRAP in setup_rt_frame()
  mn10300: don't bother with SIGTRAP in setup_frame()
  frv: no need to raise SIGTRAP in setup_frame()
  x86: get rid of duplicate code in case of CONFIG_VM86
  unicore32: remove pointless test
  h8300: trim _TIF_WORK_MASK
  parisc: decide whether to go to slow path (tracesys) based on thread flags
  parisc: don't bother looping in do_signal()
  parisc: fix double restarts
  bury the rest of TIF_IRET
  sanitize tsk_is_polling()
  bury _TIF_RESTORE_SIGMASK
  unicore32: unobfuscate _TIF_WORK_MASK
  mips: NOTIFY_RESUME is not needed in TIF masks
  mips: merge the identical "return from syscall" per-ABI code
  ...

Conflicts:
	arch/arm/include/asm/thread_info.h

arch/c6x/Kconfig

@@ -17,6 +17,7 @@ config C6X
 	select OF
 	select OF_EARLY_FLATTREE
 	select GENERIC_CLOCKEVENTS
+	select GENERIC_KERNEL_THREAD
 
 config MMU
 	def_bool n

arch/c6x/include/asm/processor.h

@@ -92,8 +92,6 @@ static inline void release_thread(struct task_struct *dead_task)
 {
 }
 
-extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
-
 #define copy_segments(tsk, mm)		do { } while (0)
 #define release_segments(mm)		do { } while (0)
 

arch/c6x/include/asm/syscalls.h

@@ -44,11 +44,6 @@ extern int sys_cache_sync(unsigned long s, unsigned long e);
 struct pt_regs;
 
 extern asmlinkage long sys_c6x_clone(struct pt_regs *regs);
-extern asmlinkage long sys_c6x_execve(const char __user *name,
-				      const char __user *const __user *argv,
-				      const char __user *const __user *envp,
-				      struct pt_regs *regs);
-
 
 #include <asm-generic/syscalls.h>
 

arch/c6x/include/asm/thread_info.h

@@ -97,7 +97,6 @@ struct thread_info *current_thread_info(void)
 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
 #define TIF_RESTORE_SIGMASK	4	/* restore signal mask in do_signal() */
 
-#define TIF_POLLING_NRFLAG	16	/* true if polling TIF_NEED_RESCHED */
 #define TIF_MEMDIE		17	/* OOM killer killed process */
 
 #define TIF_WORK_MASK		0x00007FFE /* work on irq/exception return */

arch/c6x/include/asm/unistd.h

@@ -14,6 +14,9 @@
  *   more details.
  */
 
+#define __ARCH_WANT_KERNEL_EXECVE
+#define __ARCH_WANT_SYS_EXECVE
+
 /* Use the standard ABI for syscalls. */
 #include <asm-generic/unistd.h>
 

arch/c6x/kernel/asm-offsets.c

@@ -116,7 +116,6 @@ void foo(void)
 	DEFINE(_TIF_NOTIFY_RESUME, (1<<TIF_NOTIFY_RESUME));
 	DEFINE(_TIF_SIGPENDING, (1<<TIF_SIGPENDING));
 	DEFINE(_TIF_NEED_RESCHED, (1<<TIF_NEED_RESCHED));
-	DEFINE(_TIF_POLLING_NRFLAG, (1<<TIF_POLLING_NRFLAG));
 
 	DEFINE(_TIF_ALLWORK_MASK, TIF_ALLWORK_MASK);
 	DEFINE(_TIF_WORK_MASK, TIF_WORK_MASK);

arch/c6x/kernel/entry.S

@@ -400,6 +400,32 @@ ret_from_fork_2:
 	STW	.D2T2	B0,*+SP(REGS_A4+8)
 ENDPROC(ret_from_fork)
 
+ENTRY(ret_from_kernel_thread)
+#ifdef CONFIG_C6X_BIG_KERNEL
+	MVKL	.S1	schedule_tail,A0
+	MVKH	.S1	schedule_tail,A0
+	B	.S2X	A0
+#else
+	B	.S2	schedule_tail
+#endif
+	LDW	.D2T2	*+SP(REGS_A0+8),B10 /* get fn  */
+	ADDKPC	.S2	0f,B3,3
+0:
+	B	.S2	B10		   /* call fn */
+	LDW	.D2T1	*+SP(REGS_A1+8),A4 /* get arg */
+	MVKL	.S2	sys_exit,B11
+	MVKH	.S2	sys_exit,B11
+	ADDKPC	.S2	0f,B3,1
+0:
+	BNOP	.S2	B11,5	/* jump to sys_exit */
+ENDPROC(ret_from_kernel_thread)
+
+ENTRY(ret_from_kernel_execve)
+	GET_THREAD_INFO A12
+	BNOP	.S2	syscall_exit,4
+	ADD	.D2X	A4,-8,SP
+ENDPROC(ret_from_kernel_execve)
+
 	;;
 	;; These are the interrupt handlers, responsible for calling __do_IRQ()
 	;; int6 is used for syscalls (see _system_call entry)
@@ -593,13 +619,6 @@ ENTRY(sys_sigaltstack)
 	NOP	4
 ENDPROC(sys_sigaltstack)
 
-	;; kernel_execve
-ENTRY(kernel_execve)
-	MVK	.S2	__NR_execve,B0
-	SWE
-	BNOP	.S2	B3,5
-ENDPROC(kernel_execve)
-
 	;;
 	;; Special system calls
 	;; return address is in B3
@@ -628,29 +647,6 @@ ENTRY(sys_rt_sigreturn)
 #endif
 ENDPROC(sys_rt_sigreturn)
 
-ENTRY(sys_execve)
-	ADDAW	.D2	SP,2,B6		; put regs addr in 4th parameter
-					; & adjust regs stack addr
-	LDW	.D2T2	*+SP(REGS_B4+8),B4
-
-	;; c6x_execve(char *name, char **argv,
-	;;            char **envp, struct pt_regs *regs)
-#ifdef CONFIG_C6X_BIG_KERNEL
- ||	MVKL	.S1	sys_c6x_execve,A0
-	MVKH	.S1	sys_c6x_execve,A0
-	B	.S2X	A0
-#else
- ||	B	.S2	sys_c6x_execve
-#endif
-	STW	.D2T2	B3,*SP--[2]
-	ADDKPC	.S2	ret_from_c6x_execve,B3,3
-
-ret_from_c6x_execve:
-	LDW	.D2T2	*++SP[2],B3
-	NOP	4
-	BNOP	.S2	B3,5
-ENDPROC(sys_execve)
-
 ENTRY(sys_pread_c6x)
 	MV	.D2X	A8,B7
 #ifdef CONFIG_C6X_BIG_KERNEL

arch/c6x/kernel/process.c

@@ -25,6 +25,7 @@ void	(*c6x_restart)(void);
 void	(*c6x_halt)(void);
 
 extern asmlinkage void ret_from_fork(void);
+extern asmlinkage void ret_from_kernel_thread(void);
 
 /*
  * power off function, if any
@@ -103,37 +104,6 @@ void machine_power_off(void)
 	halt_loop();
 }
 
-static void kernel_thread_helper(int dummy, void *arg, int (*fn)(void *))
-{
-	do_exit(fn(arg));
-}
-
-/*
- * Create a kernel thread
- */
-int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
-{
-	struct pt_regs regs;
-
-	/*
-	 * copy_thread sets a4 to zero (child return from fork)
-	 * so we can't just set things up to directly return to
-	 * fn.
-	 */
-	memset(&regs, 0, sizeof(regs));
-	regs.b4 = (unsigned long) arg;
-	regs.a6 = (unsigned long) fn;
-	regs.pc = (unsigned long) kernel_thread_helper;
-	local_save_flags(regs.csr);
-	regs.csr |= 1;
-	regs.tsr = 5; /* Set GEE and GIE in TSR */
-
-	/* Ok, create the new process.. */
-	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, -1, &regs,
-		       0, NULL, NULL);
-}
-EXPORT_SYMBOL(kernel_thread);
-
 void flush_thread(void)
 {
 }
@@ -191,22 +161,24 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 
 	childregs = task_pt_regs(p);
 
-	*childregs = *regs;
-	childregs->a4 = 0;
-
-	if (usp == -1)
+	if (!regs) {
 		/* case of  __kernel_thread: we return to supervisor space */
+		memset(childregs, 0, sizeof(struct pt_regs));
 		childregs->sp = (unsigned long)(childregs + 1);
-	else
+		p->thread.pc = (unsigned long) ret_from_kernel_thread;
+		childregs->a0 = usp;		/* function */
+		childregs->a1 = ustk_size;	/* argument */
+	} else {
 		/* Otherwise use the given stack */
+		*childregs = *regs;
 		childregs->sp = usp;
+		p->thread.pc = (unsigned long) ret_from_fork;
+	}
 
 	/* Set usp/ksp */
 	p->thread.usp = childregs->sp;
-	/* switch_to uses stack to save/restore 14 callee-saved regs */
 	thread_saved_ksp(p) = (unsigned long)childregs - 8;
-	p->thread.pc = (unsigned int) ret_from_fork;
-	p->thread.wchan	= (unsigned long) ret_from_fork;
+	p->thread.wchan	= p->thread.pc;
 #ifdef __DSBT__
 	{
 		unsigned long dp;
@@ -221,28 +193,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	return 0;
 }
 
-/*
- * c6x_execve() executes a new program.
- */
-SYSCALL_DEFINE4(c6x_execve, const char __user *, name,
-		const char __user *const __user *, argv,
-		const char __user *const __user *, envp,
-		struct pt_regs *, regs)
-{
-	int error;
-	char *filename;
-
-	filename = getname(name);
-	error = PTR_ERR(filename);
-	if (IS_ERR(filename))
-		goto out;
-
-	error = do_execve(filename, argv, envp, regs);
-	putname(filename);
-out:
-	return error;
-}
-
 unsigned long get_wchan(struct task_struct *p)
 {
 	return p->thread.wchan;