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

Pull signal handling cleanups from Al Viro:
 "This is the first pile; another one will come a bit later and will
  contain SYSCALL_DEFINE-related patches.

   - a bunch of signal-related syscalls (both native and compat)
     unified.

   - a bunch of compat syscalls switched to COMPAT_SYSCALL_DEFINE
     (fixing several potential problems with missing argument
     validation, while we are at it)

   - a lot of now-pointless wrappers killed

   - a couple of architectures (cris and hexagon) forgot to save
     altstack settings into sigframe, even though they used the
     (uninitialized) values in sigreturn; fixed.

   - microblaze fixes for delivery of multiple signals arriving at once

   - saner set of helpers for signal delivery introduced, several
     architectures switched to using those."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (143 commits)
  x86: convert to ksignal
  sparc: convert to ksignal
  arm: switch to struct ksignal * passing
  alpha: pass k_sigaction and siginfo_t using ksignal pointer
  burying unused conditionals
  make do_sigaltstack() static
  arm64: switch to generic old sigaction() (compat-only)
  arm64: switch to generic compat rt_sigaction()
  arm64: switch compat to generic old sigsuspend
  arm64: switch to generic compat rt_sigqueueinfo()
  arm64: switch to generic compat rt_sigpending()
  arm64: switch to generic compat rt_sigprocmask()
  arm64: switch to generic sigaltstack
  sparc: switch to generic old sigsuspend
  sparc: COMPAT_SYSCALL_DEFINE does all sign-extension as well as SYSCALL_DEFINE
  sparc: kill sign-extending wrappers for native syscalls
  kill sparc32_open()
  sparc: switch to use of generic old sigaction
  sparc: switch sys_compat_rt_sigaction() to COMPAT_SYSCALL_DEFINE
  mips: switch to generic sys_fork() and sys_clone()
  ...

arch/unicore32/kernel/entry.S

@@ -674,11 +674,6 @@ ENTRY(sys_rt_sigreturn)
 		b	__sys_rt_sigreturn
 ENDPROC(sys_rt_sigreturn)
 
-ENTRY(sys_sigaltstack)
-		ldw	r2, [sp+], #S_OFF + S_SP
-		b	do_sigaltstack
-ENDPROC(sys_sigaltstack)
-
 	__INIT
 
 /*

arch/unicore32/kernel/signal.c

@@ -123,8 +123,7 @@ asmlinkage int __sys_rt_sigreturn(struct pt_regs *regs)
 	if (restore_sigframe(regs, &frame->sig))
 		goto badframe;
 
-	if (do_sigaltstack(&frame->sig.uc.uc_stack, NULL, regs->UCreg_sp)
-			== -EFAULT)
+	if (restore_altstack(&frame->sig.uc.uc_stack))
 		goto badframe;
 
 	return regs->UCreg_00;
@@ -265,7 +264,6 @@ static int setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info,
 {
 	struct rt_sigframe __user *frame =
 			get_sigframe(ka, regs, sizeof(*frame));
-	stack_t stack;
 	int err = 0;
 
 	if (!frame)
@@ -275,13 +273,7 @@ static int setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info,
 
 	err |= __put_user(0, &frame->sig.uc.uc_flags);
 	err |= __put_user(NULL, &frame->sig.uc.uc_link);
-
-	memset(&stack, 0, sizeof(stack));
-	stack.ss_sp = (void __user *)current->sas_ss_sp;
-	stack.ss_flags = sas_ss_flags(regs->UCreg_sp);
-	stack.ss_size = current->sas_ss_size;
-	err |= __copy_to_user(&frame->sig.uc.uc_stack, &stack, sizeof(stack));
-
+	err |= __save_altstack(&frame->sig.uc.uc_stack, regs->UCreg_sp);
 	err |= setup_sigframe(&frame->sig, regs, set);
 	if (err == 0)
 		err |= setup_return(regs, ka, frame->sig.retcode, frame, usig);