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

6 files changed, 21 insertions, 21 deletions

diff --git a/arch/tile/include/asm/compat.h b/arch/tile/include/asm/compat.h
index 3063e6fc8daa..ca61fb4296b3 100644
--- a/arch/tile/include/asm/compat.h
+++ b/arch/tile/include/asm/compat.h
@@ -275,18 +275,14 @@ extern int compat_setup_rt_frame(int sig, struct k_sigaction *ka,
 struct compat_sigaction;
 struct compat_siginfo;
 struct compat_sigaltstack;
-long compat_sys_execve(const char __user *path,
-                       compat_uptr_t __user *argv,
-                       compat_uptr_t __user *envp, struct pt_regs *);
 long compat_sys_rt_sigaction(int sig, struct compat_sigaction __user *act,
                              struct compat_sigaction __user *oact,
                              size_t sigsetsize);
 long compat_sys_rt_sigqueueinfo(int pid, int sig,
                                 struct compat_siginfo __user *uinfo);
-long compat_sys_rt_sigreturn(struct pt_regs *);
+long compat_sys_rt_sigreturn(void);
 long compat_sys_sigaltstack(const struct compat_sigaltstack __user *uss_ptr,
-                            struct compat_sigaltstack __user *uoss_ptr,
-                            struct pt_regs *);
+                            struct compat_sigaltstack __user *uoss_ptr);
 long compat_sys_truncate64(char __user *filename, u32 dummy, u32 low, u32 high);
 long compat_sys_ftruncate64(unsigned int fd, u32 dummy, u32 low, u32 high);
 long compat_sys_pread64(unsigned int fd, char __user *ubuf, size_t count,
@@ -303,12 +299,7 @@ long compat_sys_fallocate(int fd, int mode,
 long compat_sys_sched_rr_get_interval(compat_pid_t pid,
                                       struct compat_timespec __user *interval);
 
-/* These are the intvec_64.S trampolines. */
-long _compat_sys_execve(const char __user *path,
-                        const compat_uptr_t __user *argv,
-                        const compat_uptr_t __user *envp);
-long _compat_sys_sigaltstack(const struct compat_sigaltstack __user *uss_ptr,
-                            struct compat_sigaltstack __user *uoss_ptr);
+/* Assembly trampoline to avoid clobbering r0. */
 long _compat_sys_rt_sigreturn(void);
 
 #endif /* _ASM_TILE_COMPAT_H */
diff --git a/arch/tile/include/asm/elf.h b/arch/tile/include/asm/elf.h
index f8ccf08f6934..b73e1039c911 100644
--- a/arch/tile/include/asm/elf.h
+++ b/arch/tile/include/asm/elf.h
@@ -148,6 +148,7 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm,
 #define compat_start_thread(regs, ip, usp) do { \
                 regs->pc = ptr_to_compat_reg((void *)(ip)); \
                 regs->sp = ptr_to_compat_reg((void *)(usp)); \
+                single_step_execve();   \
         } while (0)
 
 /*
diff --git a/arch/tile/include/asm/processor.h b/arch/tile/include/asm/processor.h
index 8c4dd9ff91eb..2b70dfb1442e 100644
--- a/arch/tile/include/asm/processor.h
+++ b/arch/tile/include/asm/processor.h
@@ -211,6 +211,7 @@ static inline void start_thread(struct pt_regs *regs,
 {
         regs->pc = pc;
         regs->sp = usp;
+        single_step_execve();
 }
 
 /* Free all resources held by a thread. */
@@ -219,8 +220,6 @@ static inline void release_thread(struct task_struct *dead_task)
         /* Nothing for now */
 }
 
-extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
-
 extern int do_work_pending(struct pt_regs *regs, u32 flags);
 
 
@@ -239,6 +238,9 @@ unsigned long get_wchan(struct task_struct *p);
 #define KSTK_TOP(task)  (task_ksp0(task) - STACK_TOP_DELTA)
 #define task_pt_regs(task) \
   ((struct pt_regs *)(task_ksp0(task) - KSTK_PTREGS_GAP) - 1)
+#define current_pt_regs()                                   \
+  ((struct pt_regs *)((stack_pointer | (THREAD_SIZE - 1)) - \
+                      (KSTK_PTREGS_GAP - 1)) - 1)
 #define task_sp(task)   (task_pt_regs(task)->sp)
 #define task_pc(task)   (task_pt_regs(task)->pc)
 /* Aliases for pc and sp (used in fs/proc/array.c) */
diff --git a/arch/tile/include/asm/switch_to.h b/arch/tile/include/asm/switch_to.h
index 1d48c5fee8b7..b8f888cbe6b0 100644
--- a/arch/tile/include/asm/switch_to.h
+++ b/arch/tile/include/asm/switch_to.h
@@ -68,7 +68,10 @@ extern unsigned long get_switch_to_pc(void);
 /* Support function for forking a new task. */
 void ret_from_fork(void);
 
-/* Called from ret_from_fork() when a new process starts up. */
+/* Support function for forking a new kernel thread. */
+void ret_from_kernel_thread(void *fn, void *arg);
+
+/* Called from ret_from_xxx() when a new process starts up. */
 struct task_struct *sim_notify_fork(struct task_struct *prev);
 
 #endif /* !__ASSEMBLY__ */
diff --git a/arch/tile/include/asm/syscalls.h b/arch/tile/include/asm/syscalls.h
index 06f0464cfed9..4c8462a62cb6 100644
--- a/arch/tile/include/asm/syscalls.h
+++ b/arch/tile/include/asm/syscalls.h
@@ -51,8 +51,7 @@ long sys_cacheflush(unsigned long addr, unsigned long len,
 
 #ifndef __tilegx__
 /* mm/fault.c */
-long sys_cmpxchg_badaddr(unsigned long address, struct pt_regs *);
-long _sys_cmpxchg_badaddr(unsigned long address);
+long sys_cmpxchg_badaddr(unsigned long address);
 #endif
 
 #ifdef CONFIG_COMPAT
@@ -63,14 +62,16 @@ long sys_truncate64(const char __user *path, loff_t length);
 long sys_ftruncate64(unsigned int fd, loff_t length);
 #endif
 
+/* Provide versions of standard syscalls that use current_pt_regs(). */
+long sys_rt_sigreturn(void);
+long sys_sigaltstack(const stack_t __user *, stack_t __user *);
+#define sys_rt_sigreturn sys_rt_sigreturn
+#define sys_sigaltstack sys_sigaltstack
+
 /* These are the intvec*.S trampolines. */
-long _sys_sigaltstack(const stack_t __user *, stack_t __user *);
 long _sys_rt_sigreturn(void);
 long _sys_clone(unsigned long clone_flags, unsigned long newsp,
                 void __user *parent_tid, void __user *child_tid);
-long _sys_execve(const char __user *filename,
-                 const char __user *const __user *argv,
-                 const char __user *const __user *envp);
 
 #include <asm-generic/syscalls.h>
 
diff --git a/arch/tile/include/asm/unistd.h b/arch/tile/include/asm/unistd.h
index 6e032a0a268e..b51c6ee3cd6c 100644
--- a/arch/tile/include/asm/unistd.h
+++ b/arch/tile/include/asm/unistd.h
@@ -16,4 +16,6 @@
 #define __ARCH_WANT_SYS_LLSEEK
 #endif
 #define __ARCH_WANT_SYS_NEWFSTATAT
+#define __ARCH_WANT_SYS_EXECVE
+#define __ARCH_WANT_SYS_CLONE
 #include <uapi/asm/unistd.h>