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

4 files changed, 25 insertions, 36 deletions

diff --git a/arch/parisc/hpux/gate.S b/arch/parisc/hpux/gate.S
index 38a1c1b8d4e..011468857e9 100644
--- a/arch/parisc/hpux/gate.S
+++ b/arch/parisc/hpux/gate.S
@@ -71,7 +71,7 @@ ENTRY(hpux_gateway_page)
 	STREG	%r26, TASK_PT_GR26(%r1)	 	/* 1st argument */
 	STREG	%r27, TASK_PT_GR27(%r1)		/* user dp */
 	STREG   %r28, TASK_PT_GR28(%r1)         /* return value 0 */
-	STREG   %r28, TASK_PT_ORIG_R28(%r1)     /* return value 0 (saved for signals) */
+	STREG   %r0, TASK_PT_ORIG_R28(%r1)     /* don't prohibit restarts */
 	STREG   %r29, TASK_PT_GR29(%r1)         /* 8th argument */
 	STREG	%r31, TASK_PT_GR31(%r1)		/* preserve syscall return ptr */
 	
diff --git a/arch/parisc/include/asm/thread_info.h b/arch/parisc/include/asm/thread_info.h
index 22b4726dee4..d1fb79a36f3 100644
--- a/arch/parisc/include/asm/thread_info.h
+++ b/arch/parisc/include/asm/thread_info.h
@@ -68,13 +68,16 @@ struct thread_info {
 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
 #define _TIF_32BIT		(1 << TIF_32BIT)
-#define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
 #define _TIF_SINGLESTEP		(1 << TIF_SINGLESTEP)
 #define _TIF_BLOCKSTEP		(1 << TIF_BLOCKSTEP)
 
 #define _TIF_USER_WORK_MASK     (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | \
                                  _TIF_NEED_RESCHED)
+#define _TIF_SYSCALL_TRACE_MASK (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP |	\
+				 _TIF_BLOCKSTEP)
+
+#define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG)
 
 #endif /* __KERNEL__ */
 
diff --git a/arch/parisc/kernel/signal.c b/arch/parisc/kernel/signal.c
index 594459bde14..53799695599 100644
--- a/arch/parisc/kernel/signal.c
+++ b/arch/parisc/kernel/signal.c
@@ -113,6 +113,8 @@ sys_rt_sigreturn(struct pt_regs *regs, int in_syscall)
 		(usp - sigframe_size);
 	DBG(2,"sys_rt_sigreturn: frame is %p\n", frame);
 
+	regs->orig_r28 = 1; /* no restarts for sigreturn */
+
 #ifdef CONFIG_64BIT
 	compat_frame = (struct compat_rt_sigframe __user *)frame;
 	
@@ -437,7 +439,7 @@ give_sigsegv:
  * OK, we're invoking a handler.
  */	
 
-static long
+static void
 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 		struct pt_regs *regs, int in_syscall)
 {
@@ -447,7 +449,7 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	
 	/* Set up the stack frame */
 	if (!setup_rt_frame(sig, ka, info, oldset, regs, in_syscall))
-		return 0;
+		return;
 
 	signal_delivered(sig, info, ka, regs, 
 		test_thread_flag(TIF_SINGLESTEP) ||
@@ -455,13 +457,14 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 
 	DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
 		regs->gr[28]);
-
-	return 1;
 }
 
 static inline void
 syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
 {
+	if (regs->orig_r28)
+		return;
+	regs->orig_r28 = 1; /* no more restarts */
 	/* Check the return code */
 	switch (regs->gr[28]) {
 	case -ERESTART_RESTARTBLOCK:
@@ -482,8 +485,6 @@ syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
 		 * we have to do is fiddle the return pointer.
 		 */
 		regs->gr[31] -= 8; /* delayed branching */
-		/* Preserve original r28. */
-		regs->gr[28] = regs->orig_r28;
 		break;
 	}
 }
@@ -491,6 +492,9 @@ syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
 static inline void
 insert_restart_trampoline(struct pt_regs *regs)
 {
+	if (regs->orig_r28)
+		return;
+	regs->orig_r28 = 1; /* no more restarts */
 	switch(regs->gr[28]) {
 	case -ERESTART_RESTARTBLOCK: {
 		/* Restart the system call - no handlers present */
@@ -525,9 +529,6 @@ insert_restart_trampoline(struct pt_regs *regs)
 		flush_user_icache_range(regs->gr[30], regs->gr[30] + 4);
 
 		regs->gr[31] = regs->gr[30] + 8;
-		/* Preserve original r28. */
-		regs->gr[28] = regs->orig_r28;
-
 		return;
 	}
 	case -ERESTARTNOHAND:
@@ -539,9 +540,6 @@ insert_restart_trampoline(struct pt_regs *regs)
 		 * slot of the branch external instruction.
 		 */
 		regs->gr[31] -= 8;
-		/* Preserve original r28. */
-		regs->gr[28] = regs->orig_r28;
-
 		return;
 	}
 	default:
@@ -570,30 +568,17 @@ do_signal(struct pt_regs *regs, long in_syscall)
 	DBG(1,"\ndo_signal: regs=0x%p, sr7 %#lx, in_syscall=%d\n",
 	       regs, regs->sr[7], in_syscall);
 
-	/* Everyone else checks to see if they are in kernel mode at
-	   this point and exits if that's the case.  I'm not sure why
-	   we would be called in that case, but for some reason we
-	   are. */
-
-	/* May need to force signal if handle_signal failed to deliver */
-	while (1) {
-		signr = get_signal_to_deliver(&info, &ka, regs, NULL);
-		DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]); 
+	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
+	DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]); 
 	
-		if (signr <= 0)
-		  break;
-		
+	if (signr > 0) {
 		/* Restart a system call if necessary. */
 		if (in_syscall)
 			syscall_restart(regs, &ka);
 
-		/* Whee!  Actually deliver the signal.  If the
-		   delivery failed, we need to continue to iterate in
-		   this loop so we can deliver the SIGSEGV... */
-		if (handle_signal(signr, &info, &ka, regs, in_syscall))
-			return;
+		handle_signal(signr, &info, &ka, regs, in_syscall);
+		return;
 	}
-	/* end of while(1) looping forever if we can't force a signal */
 
 	/* Did we come from a system call? */
 	if (in_syscall)
diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S
index 82a52b2fb13..86742df0b19 100644
--- a/arch/parisc/kernel/syscall.S
+++ b/arch/parisc/kernel/syscall.S
@@ -156,7 +156,7 @@ linux_gateway_entry:
 	STREG	%r26, TASK_PT_GR26(%r1)	 	/* 1st argument */
 	STREG	%r27, TASK_PT_GR27(%r1)		/* user dp */
 	STREG   %r28, TASK_PT_GR28(%r1)         /* return value 0 */
-	STREG   %r28, TASK_PT_ORIG_R28(%r1)     /* return value 0 (saved for signals) */
+	STREG   %r0, TASK_PT_ORIG_R28(%r1)      /* don't prohibit restarts */
 	STREG	%r29, TASK_PT_GR29(%r1)		/* return value 1 */
 	STREG	%r31, TASK_PT_GR31(%r1)		/* preserve syscall return ptr */
 	
@@ -180,9 +180,10 @@ linux_gateway_entry:
 
 	/* Are we being ptraced? */
 	mfctl	%cr30, %r1
-	LDREG	TI_TASK(%r1),%r1
-	ldw	TASK_PTRACE(%r1), %r1
-	bb,<,n	%r1,31,.Ltracesys
+	LDREG	TI_FLAGS(%r1),%r1
+	ldi	_TIF_SYSCALL_TRACE_MASK, %r19
+	and,COND(=) %r1, %r19, %r0
+	b,n	.Ltracesys
 	
 	/* Note!  We cannot use the syscall table that is mapped
 	nearby since the gateway page is mapped execute-only. */