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

12 files changed, 45 insertions, 174 deletions

diff --git a/arch/frv/Kconfig b/arch/frv/Kconfig
index 9d262645f667..b7412504f08a 100644
--- a/arch/frv/Kconfig
+++ b/arch/frv/Kconfig
@@ -12,6 +12,7 @@ config FRV
         select ARCH_HAVE_NMI_SAFE_CMPXCHG
         select GENERIC_CPU_DEVICES
         select ARCH_WANT_IPC_PARSE_VERSION
+        select GENERIC_KERNEL_THREAD
 
 config ZONE_DMA
         bool
diff --git a/arch/frv/include/asm/processor.h b/arch/frv/include/asm/processor.h
index dccb9d162318..a34f309e5801 100644
--- a/arch/frv/include/asm/processor.h
+++ b/arch/frv/include/asm/processor.h
@@ -92,14 +92,12 @@ extern struct task_struct *__kernel_current_task;
 
 /*
  * do necessary setup to start up a newly executed thread.
- * - need to discard the frame stacked by init() invoking the execve syscall
  */
 #define start_thread(_regs, _pc, _usp)                  \
 do {                                                    \
-        __frame = __kernel_frame0_ptr;                  \
-        __frame->pc     = (_pc);                        \
-        __frame->psr    &= ~PSR_S;                      \
-        __frame->sp     = (_usp);                       \
+        _regs->pc       = (_pc);                        \
+        _regs->psr      &= ~PSR_S;                      \
+        _regs->sp       = (_usp);                       \
 } while(0)
 
 /* Free all resources held by a thread. */
@@ -107,7 +105,6 @@ static inline void release_thread(struct task_struct *dead_task)
 {
 }
 
-extern asmlinkage int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
 extern asmlinkage void save_user_regs(struct user_context *target);
 extern asmlinkage void *restore_user_regs(const struct user_context *target, ...);
 
diff --git a/arch/frv/include/asm/ptrace.h b/arch/frv/include/asm/ptrace.h
index ef6635ca4ecb..bd534b2d0258 100644
--- a/arch/frv/include/asm/ptrace.h
+++ b/arch/frv/include/asm/ptrace.h
@@ -76,6 +76,7 @@ register struct pt_regs *__frame asm("gr28");
 #define user_mode(regs)                 (!((regs)->psr & PSR_S))
 #define instruction_pointer(regs)       ((regs)->pc)
 #define user_stack_pointer(regs)        ((regs)->sp)
+#define current_pt_regs()               (__frame)
 
 extern unsigned long user_stack(const struct pt_regs *);
 #define profile_pc(regs) ((regs)->pc)
diff --git a/arch/frv/include/asm/thread_info.h b/arch/frv/include/asm/thread_info.h
index 0ff03a33c81e..bebd7eadc772 100644
--- a/arch/frv/include/asm/thread_info.h
+++ b/arch/frv/include/asm/thread_info.h
@@ -94,7 +94,6 @@ register struct thread_info *__current_thread_info asm("gr15");
 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 #define TIF_SINGLESTEP          4       /* restore singlestep on return to user mode */
 #define TIF_RESTORE_SIGMASK     5       /* restore signal mask in do_signal() */
-#define TIF_POLLING_NRFLAG      6       /* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_MEMDIE              7       /* is terminating due to OOM killer */
 
 #define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
@@ -102,8 +101,6 @@ register struct thread_info *__current_thread_info asm("gr15");
 #define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
 #define _TIF_SINGLESTEP         (1 << TIF_SINGLESTEP)
-#define _TIF_RESTORE_SIGMASK    (1 << TIF_RESTORE_SIGMASK)
-#define _TIF_POLLING_NRFLAG     (1 << TIF_POLLING_NRFLAG)
 
 /* work to do on interrupt/exception return */
 #define _TIF_WORK_MASK          \
diff --git a/arch/frv/include/asm/unistd.h b/arch/frv/include/asm/unistd.h
index 67f23a311db6..b6b07e55e473 100644
--- a/arch/frv/include/asm/unistd.h
+++ b/arch/frv/include/asm/unistd.h
@@ -372,6 +372,8 @@
 #define __ARCH_WANT_SYS_SIGPROCMASK
 #define __ARCH_WANT_SYS_RT_SIGACTION
 #define __ARCH_WANT_SYS_RT_SIGSUSPEND
+#define __ARCH_WANT_SYS_EXECVE
+#define __ARCH_WANT_KERNEL_EXECVE
 
 /*
  * "Conditional" syscalls
diff --git a/arch/frv/kernel/Makefile b/arch/frv/kernel/Makefile
index ad4087b69968..3cbb3294b9f9 100644
--- a/arch/frv/kernel/Makefile
+++ b/arch/frv/kernel/Makefile
@@ -7,8 +7,8 @@ heads-$(CONFIG_MMU)		:= head-mmu-fr451.o
 
 extra-y:= head.o vmlinux.lds
 
-obj-y := $(heads-y) entry.o entry-table.o break.o switch_to.o kernel_thread.o \
-         kernel_execve.o process.o traps.o ptrace.o signal.o dma.o \
+obj-y := $(heads-y) entry.o entry-table.o break.o switch_to.o \
+         process.o traps.o ptrace.o signal.o dma.o \
          sys_frv.o time.o setup.o frv_ksyms.o \
          debug-stub.o irq.o sleep.o uaccess.o
 
diff --git a/arch/frv/kernel/entry.S b/arch/frv/kernel/entry.S
index 7d5e000fd32e..002732960315 100644
--- a/arch/frv/kernel/entry.S
+++ b/arch/frv/kernel/entry.S
@@ -863,6 +863,19 @@ ret_from_fork:
         setlos.p        #0,gr8
         bra             __syscall_exit
 
+        .globl          ret_from_kernel_thread
+ret_from_kernel_thread:
+        lddi.p          @(gr28,#REG_GR(8)),gr20
+        call            schedule_tail
+        or.p            gr20,gr20,gr8
+        calll           @(gr21,gr0)
+        bra             sys_exit
+
+        .globl          ret_from_kernel_execve
+ret_from_kernel_execve:
+        ori             gr28,0,sp
+        bra             __syscall_exit
+
 ###################################################################################################
 #
 # Return to user mode is not as complex as all this looks,
diff --git a/arch/frv/kernel/frv_ksyms.c b/arch/frv/kernel/frv_ksyms.c
index a89803b58b9a..86c516d96dcd 100644
--- a/arch/frv/kernel/frv_ksyms.c
+++ b/arch/frv/kernel/frv_ksyms.c
@@ -30,7 +30,6 @@ EXPORT_SYMBOL(ip_fast_csum);
 EXPORT_SYMBOL(local_irq_count);
 EXPORT_SYMBOL(local_bh_count);
 #endif
-EXPORT_SYMBOL(kernel_thread);
 
 EXPORT_SYMBOL(__res_bus_clock_speed_HZ);
 EXPORT_SYMBOL(__page_offset);
diff --git a/arch/frv/kernel/kernel_execve.S b/arch/frv/kernel/kernel_execve.S
deleted file mode 100644
index 9b074a16a052..000000000000
--- a/arch/frv/kernel/kernel_execve.S
+++ /dev/null
@@ -1,33 +0,0 @@
-/* in-kernel program execution
- *
- * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#include <linux/linkage.h>
-#include <asm/unistd.h>
-
-###############################################################################
-#
-# Do a system call from kernel instead of calling sys_execve so we end up with
-# proper pt_regs.
-#
-# int kernel_execve(const char *filename, char *const argv[], char *const envp[])
-#
-# On entry: GR8/GR9/GR10: arguments to function
-# On return: GR8: syscall return.
-#
-###############################################################################
-        .globl          kernel_execve
-        .type           kernel_execve,@function
-kernel_execve:
-        setlos          __NR_execve,gr7
-        tira            gr0,#0
-        bralr
-
-        .size           kernel_execve,.-kernel_execve
diff --git a/arch/frv/kernel/kernel_thread.S b/arch/frv/kernel/kernel_thread.S
deleted file mode 100644
index f0e52943f923..000000000000
--- a/arch/frv/kernel/kernel_thread.S
+++ /dev/null
@@ -1,77 +0,0 @@
-/* kernel_thread.S: kernel thread creation
- *
- * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#include <linux/linkage.h>
-#include <linux/kern_levels.h>
-#include <asm/unistd.h>
-
-#define CLONE_VM        0x00000100      /* set if VM shared between processes */
-
-        .section .rodata
-kernel_thread_emsg:
-        .asciz  KERN_ERR "failed to create kernel thread: error=%d\n"
-
-        .text
-        .balign         4
-
-###############################################################################
-#
-# Create a kernel thread
-#
-# int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
-#
-###############################################################################
-        .globl          kernel_thread
-        .type           kernel_thread,@function
-kernel_thread:
-        or.p            gr8,gr0,gr4
-        or              gr9,gr0,gr5
-
-        # start by forking the current process, but with shared VM
-        setlos.p        #__NR_clone,gr7         ; syscall number
-        ori             gr10,#CLONE_VM,gr8      ; first syscall arg     [clone_flags]
-        sethi.p         #0xe4e4,gr9             ; second syscall arg    [newsp]
-        setlo           #0xe4e4,gr9
-        setlos.p        #0,gr10                 ; third syscall arg     [parent_tidptr]
-        setlos          #0,gr11                 ; fourth syscall arg    [child_tidptr]
-        tira            gr0,#0
-        setlos.p        #4095,gr7
-        andcc           gr8,gr8,gr0,icc0
-        addcc.p         gr8,gr7,gr0,icc1
-        bnelr           icc0,#2
-        bc              icc1,#0,kernel_thread_error
-
-        # now invoke the work function
-        or              gr5,gr0,gr8
-        calll           @(gr4,gr0)
-
-        # and finally exit the thread
-        setlos          #__NR_exit,gr7          ; syscall number
-        tira            gr0,#0
-
-kernel_thread_error:
-        subi            sp,#8,sp
-        movsg           lr,gr4
-        sti             gr8,@(sp,#0)
-        sti.p           gr4,@(sp,#4)
-
-        or              gr8,gr0,gr9
-        sethi.p         %hi(kernel_thread_emsg),gr8
-        setlo           %lo(kernel_thread_emsg),gr8
-
-        call            printk
-
-        ldi             @(sp,#4),gr4
-        ldi             @(sp,#0),gr8
-        subi            sp,#8,sp
-        jmpl            @(gr4,gr0)
-
-        .size           kernel_thread,.-kernel_thread
diff --git a/arch/frv/kernel/process.c b/arch/frv/kernel/process.c
index 2eb7fa5bf9d8..655d90d20bb0 100644
--- a/arch/frv/kernel/process.c
+++ b/arch/frv/kernel/process.c
@@ -38,6 +38,7 @@
 #include "local.h"
 
 asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
 
 #include <asm/pgalloc.h>
 
@@ -172,32 +173,13 @@ asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
  * set up the kernel stack and exception frames for a new process
  */
 int copy_thread(unsigned long clone_flags,
-                unsigned long usp, unsigned long topstk,
+                unsigned long usp, unsigned long arg,
                 struct task_struct *p, struct pt_regs *regs)
 {
-        struct pt_regs *childregs0, *childregs, *regs0;
+        struct pt_regs *childregs;
 
-        regs0 = __kernel_frame0_ptr;
-        childregs0 = (struct pt_regs *)
+        childregs = (struct pt_regs *)
                 (task_stack_page(p) + THREAD_SIZE - FRV_FRAME0_SIZE);
-        childregs = childregs0;
-
-        /* set up the userspace frame (the only place that the USP is stored) */
-        *childregs0 = *regs0;
-
-        childregs0->gr8         = 0;
-        childregs0->sp          = usp;
-        childregs0->next_frame  = NULL;
-
-        /* set up the return kernel frame if called from kernel_thread() */
-        if (regs != regs0) {
-                childregs--;
-                *childregs = *regs;
-                childregs->sp = (unsigned long) childregs0;
-                childregs->next_frame = childregs0;
-                childregs->gr15 = (unsigned long) task_thread_info(p);
-                childregs->gr29 = (unsigned long) p;
-        }
 
         p->set_child_tid = p->clear_child_tid = NULL;
 
@@ -206,8 +188,25 @@ int copy_thread(unsigned long clone_flags,
         p->thread.sp     = (unsigned long) childregs;
         p->thread.fp     = 0;
         p->thread.lr     = 0;
-        p->thread.pc     = (unsigned long) ret_from_fork;
-        p->thread.frame0 = childregs0;
+        p->thread.frame0 = childregs;
+
+        if (unlikely(!regs)) {
+                memset(childregs, 0, sizeof(struct pt_regs));
+                childregs->gr9 = usp; /* function */
+                childregs->gr8 = arg;
+                chilregs->psr = PSR_S;
+                p->thread.pc = (unsigned long) ret_from_kernel_thread;
+                save_user_regs(p->thread.user);
+                return 0;
+        }
+
+        /* set up the userspace frame (the only place that the USP is stored) */
+        *childregs = *regs;
+
+        childregs->sp           = usp;
+        childregs->next_frame   = NULL;
+
+        p->thread.pc = (unsigned long) ret_from_fork;
 
         /* the new TLS pointer is passed in as arg #5 to sys_clone() */
         if (clone_flags & CLONE_SETTLS)
@@ -218,25 +217,6 @@ int copy_thread(unsigned long clone_flags,
         return 0;
 } /* end copy_thread() */
 
-/*
- * sys_execve() executes a new program.
- */
-asmlinkage int sys_execve(const char __user *name,
-                          const char __user *const __user *argv,
-                          const char __user *const __user *envp)
-{
-        int error;
-        char * filename;
-
-        filename = getname(name);
-        error = PTR_ERR(filename);
-        if (IS_ERR(filename))
-                return error;
-        error = do_execve(filename, argv, envp, __frame);
-        putname(filename);
-        return error;
-}
-
 unsigned long get_wchan(struct task_struct *p)
 {
         struct pt_regs *regs0;
diff --git a/arch/frv/kernel/signal.c b/arch/frv/kernel/signal.c
index 864c2f0d497b..535810a3217a 100644
--- a/arch/frv/kernel/signal.c
+++ b/arch/frv/kernel/signal.c
@@ -20,7 +20,6 @@
 #include <linux/ptrace.h>
 #include <linux/unistd.h>
 #include <linux/personality.h>
-#include <linux/freezer.h>
 #include <linux/tracehook.h>
 #include <asm/ucontext.h>
 #include <asm/uaccess.h>
@@ -298,10 +297,6 @@ static int setup_frame(int sig, struct k_sigaction *ka, sigset_t *set)
         __frame->lr   = (unsigned long) &frame->retcode;
         __frame->gr8  = sig;
 
-        /* the tracer may want to single-step inside the handler */
-        if (test_thread_flag(TIF_SINGLESTEP))
-                ptrace_notify(SIGTRAP);
-
 #if DEBUG_SIG
         printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
                sig, current->comm, current->pid, frame, __frame->pc,
@@ -400,10 +395,6 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
         __frame->gr8 = sig;
         __frame->gr9 = (unsigned long) &frame->info;
 
-        /* the tracer may want to single-step inside the handler */
-        if (test_thread_flag(TIF_SINGLESTEP))
-                ptrace_notify(SIGTRAP);
-
 #if DEBUG_SIG
         printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
                sig, current->comm, current->pid, frame, __frame->pc,