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

Pull big execve/kernel_thread/fork unification series from Al Viro:
 "All architectures are converted to new model.  Quite a bit of that
  stuff is actually shared with architecture trees; in such cases it's
  literally shared branch pulled by both, not a cherry-pick.

  A lot of ugliness and black magic is gone (-3KLoC total in this one):

   - kernel_thread()/kernel_execve()/sys_execve() redesign.

     We don't do syscalls from kernel anymore for either kernel_thread()
     or kernel_execve():

     kernel_thread() is essentially clone(2) with callback run before we
     return to userland, the callbacks either never return or do
     successful do_execve() before returning.

     kernel_execve() is a wrapper for do_execve() - it doesn't need to
     do transition to user mode anymore.

     As a result kernel_thread() and kernel_execve() are
     arch-independent now - they live in kernel/fork.c and fs/exec.c
     resp.  sys_execve() is also in fs/exec.c and it's completely
     architecture-independent.

   - daemonize() is gone, along with its parts in fs/*.c

   - struct pt_regs * is no longer passed to do_fork/copy_process/
     copy_thread/do_execve/search_binary_handler/->load_binary/do_coredump.

   - sys_fork()/sys_vfork()/sys_clone() unified; some architectures
     still need wrappers (ones with callee-saved registers not saved in
     pt_regs on syscall entry), but the main part of those suckers is in
     kernel/fork.c now."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (113 commits)
  do_coredump(): get rid of pt_regs argument
  print_fatal_signal(): get rid of pt_regs argument
  ptrace_signal(): get rid of unused arguments
  get rid of ptrace_signal_deliver() arguments
  new helper: signal_pt_regs()
  unify default ptrace_signal_deliver
  flagday: kill pt_regs argument of do_fork()
  death to idle_regs()
  don't pass regs to copy_process()
  flagday: don't pass regs to copy_thread()
  bfin: switch to generic vfork, get rid of pointless wrappers
  xtensa: switch to generic clone()
  openrisc: switch to use of generic fork and clone
  unicore32: switch to generic clone(2)
  score: switch to generic fork/vfork/clone
  c6x: sanitize copy_thread(), get rid of clone(2) wrapper, switch to generic clone()
  take sys_fork/sys_vfork/sys_clone prototypes to linux/syscalls.h
  mn10300: switch to generic fork/vfork/clone
  h8300: switch to generic fork/vfork/clone
  tile: switch to generic clone()
  ...

Conflicts:
	arch/microblaze/include/asm/Kbuild

5 files changed, 10 insertions, 39 deletions

diff --git a/arch/mn10300/Kconfig b/arch/mn10300/Kconfig
index 04669fac117b..72471744a912 100644
--- a/arch/mn10300/Kconfig
+++ b/arch/mn10300/Kconfig
@@ -9,6 +9,7 @@ config MN10300
         select HAVE_NMI_WATCHDOG if MN10300_WD_TIMER
         select GENERIC_CLOCKEVENTS
         select GENERIC_KERNEL_THREAD
+        select GENERIC_KERNEL_EXECVE
         select MODULES_USE_ELF_RELA
 
 config AM33_2
diff --git a/arch/mn10300/include/asm/signal.h b/arch/mn10300/include/asm/signal.h
index f9668ec3040c..d280e9780793 100644
--- a/arch/mn10300/include/asm/signal.h
+++ b/arch/mn10300/include/asm/signal.h
@@ -45,8 +45,4 @@ struct k_sigaction {
 };
 #include <asm/sigcontext.h>
 
-
-struct pt_regs;
-#define ptrace_signal_deliver(regs, cookie) do { } while (0)
-
 #endif /* _ASM_SIGNAL_H */
diff --git a/arch/mn10300/include/asm/unistd.h b/arch/mn10300/include/asm/unistd.h
index 55bbec1887e9..cabf8ba73b27 100644
--- a/arch/mn10300/include/asm/unistd.h
+++ b/arch/mn10300/include/asm/unistd.h
@@ -44,7 +44,9 @@
 #define __ARCH_WANT_SYS_RT_SIGACTION
 #define __ARCH_WANT_SYS_RT_SIGSUSPEND
 #define __ARCH_WANT_SYS_EXECVE
-#define __ARCH_WANT_KERNEL_EXECVE
+#define __ARCH_WANT_SYS_FORK
+#define __ARCH_WANT_SYS_VFORK
+#define __ARCH_WANT_SYS_CLONE
 
 /*
  * "Conditional" syscalls
diff --git a/arch/mn10300/kernel/entry.S b/arch/mn10300/kernel/entry.S
index 0c631d34c8d7..68fcab8f8f6f 100644
--- a/arch/mn10300/kernel/entry.S
+++ b/arch/mn10300/kernel/entry.S
@@ -60,13 +60,8 @@ ENTRY(ret_from_kernel_thread)
         mov     (REG_D0,fp),d0
         mov     (REG_A0,fp),a0
         calls   (a0)
-        jmp     sys_exit
-
-ENTRY(ret_from_kernel_execve)
-        add     -12,d0  /* pt_regs -> frame */
-        mov     d0,sp
-        GET_THREAD_INFO a2
         clr     d0
+        mov     d0,(REG_D0,fp)
         jmp     syscall_exit
 
 ###############################################################################
diff --git a/arch/mn10300/kernel/process.c b/arch/mn10300/kernel/process.c
index d0c671b6d9ff..eb09f5a552ff 100644
--- a/arch/mn10300/kernel/process.c
+++ b/arch/mn10300/kernel/process.c
@@ -206,7 +206,7 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
  */
 int copy_thread(unsigned long clone_flags,
                 unsigned long c_usp, unsigned long ustk_size,
-                struct task_struct *p, struct pt_regs *kregs)
+                struct task_struct *p)
 {
         struct thread_info *ti = task_thread_info(p);
         struct pt_regs *c_regs;
@@ -227,7 +227,7 @@ int copy_thread(unsigned long clone_flags,
         p->thread.wchan = p->thread.pc;
         p->thread.usp   = c_usp;
 
-        if (unlikely(!kregs)) {
+        if (unlikely(p->flags & PF_KTHREAD)) {
                 memset(c_regs, 0, sizeof(struct pt_regs));
                 c_regs->a0 = c_usp; /* function */
                 c_regs->d0 = ustk_size; /* argument */
@@ -236,8 +236,9 @@ int copy_thread(unsigned long clone_flags,
                 p->thread.pc    = (unsigned long) ret_from_kernel_thread;
                 return 0;
         }
-        *c_regs = *kregs;
-        c_regs->sp = c_usp;
+        *c_regs = *current_pt_regs();
+        if (c_usp)
+                c_regs->sp = c_usp;
         c_regs->epsw &= ~EPSW_FE; /* my FPU */
 
         /* the new TLS pointer is passed in as arg #5 to sys_clone() */
@@ -249,30 +250,6 @@ int copy_thread(unsigned long clone_flags,
         return 0;
 }
 
-/*
- * clone a process
- * - tlsptr is retrieved by copy_thread() from current_frame()->d3
- */
-asmlinkage long sys_clone(unsigned long clone_flags, unsigned long newsp,
-                          int __user *parent_tidptr, int __user *child_tidptr,
-                          int __user *tlsptr)
-{
-        return do_fork(clone_flags, newsp ?: current_frame()->sp,
-                       current_frame(), 0, parent_tidptr, child_tidptr);
-}
-
-asmlinkage long sys_fork(void)
-{
-        return do_fork(SIGCHLD, current_frame()->sp,
-                       current_frame(), 0, NULL, NULL);
-}
-
-asmlinkage long sys_vfork(void)
-{
-        return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, current_frame()->sp,
-                       current_frame(), 0, NULL, NULL);
-}
-
 unsigned long get_wchan(struct task_struct *p)
 {
         return p->thread.wchan;