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

3 files changed, 21 insertions, 27 deletions

diff --git a/arch/alpha/include/asm/thread_info.h b/arch/alpha/include/asm/thread_info.h
index 28335bd40e40..4554ecbff7c6 100644
--- a/arch/alpha/include/asm/thread_info.h
+++ b/arch/alpha/include/asm/thread_info.h
@@ -84,7 +84,6 @@ register struct thread_info *__current_thread_info __asm__("$8");
 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)
-#define _TIF_RESTORE_SIGMASK    (1<<TIF_RESTORE_SIGMASK)
 #define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
 
 /* Work to do on interrupt/exception return.  */
@@ -117,5 +116,7 @@ register struct thread_info *__current_thread_info __asm__("$8");
                  (int __user *)(value));                                \
         })
 
+#define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG)
+
 #endif /* __KERNEL__ */
 #endif /* _ALPHA_THREAD_INFO_H */
diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S
index 7e43e1156d10..2a359c9ee3cd 100644
--- a/arch/alpha/kernel/entry.S
+++ b/arch/alpha/kernel/entry.S
@@ -418,11 +418,10 @@ $work_notifysig:
 strace:
         /* set up signal stack, call syscall_trace */
         bsr     $1, do_switch_stack
-        jsr     $26, syscall_trace
+        jsr     $26, syscall_trace_enter /* returns the syscall number */
         bsr     $1, undo_switch_stack
 
-        /* get the system call number and the arguments back.. */
-        ldq     $0, 0($sp)
+        /* get the arguments back.. */
         ldq     $16, SP_OFF+24($sp)
         ldq     $17, SP_OFF+32($sp)
         ldq     $18, SP_OFF+40($sp)
@@ -449,7 +448,7 @@ $strace_success:
         stq     $0, 0($sp)              /* save return value */
 
         bsr     $1, do_switch_stack
-        jsr     $26, syscall_trace
+        jsr     $26, syscall_trace_leave
         bsr     $1, undo_switch_stack
         br      $31, ret_from_sys_call
 
@@ -467,7 +466,7 @@ $strace_error:
         bsr     $1, do_switch_stack
         mov     $19, $9         /* save old syscall number */
         mov     $20, $10        /* save old a3 */
-        jsr     $26, syscall_trace
+        jsr     $26, syscall_trace_leave
         mov     $9, $19
         mov     $10, $20
         bsr     $1, undo_switch_stack
@@ -698,7 +697,7 @@ sys_sigreturn:
         lda     $sp, -SWITCH_STACK_SIZE($sp)
         jsr     $26, do_sigreturn
         bne     $9, 1f
-        jsr     $26, syscall_trace
+        jsr     $26, syscall_trace_leave
 1:      br      $1, undo_switch_stack
         br      ret_from_sys_call
 .end sys_sigreturn
@@ -715,7 +714,7 @@ sys_rt_sigreturn:
         lda     $sp, -SWITCH_STACK_SIZE($sp)
         jsr     $26, do_rt_sigreturn
         bne     $9, 1f
-        jsr     $26, syscall_trace
+        jsr     $26, syscall_trace_leave
 1:      br      $1, undo_switch_stack
         br      ret_from_sys_call
 .end sys_rt_sigreturn
diff --git a/arch/alpha/kernel/ptrace.c b/arch/alpha/kernel/ptrace.c
index 54616f496aed..2a4a80ff4a20 100644
--- a/arch/alpha/kernel/ptrace.c
+++ b/arch/alpha/kernel/ptrace.c
@@ -13,6 +13,7 @@
 #include <linux/user.h>
 #include <linux/security.h>
 #include <linux/signal.h>
+#include <linux/tracehook.h>
 
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
@@ -312,25 +313,18 @@ long arch_ptrace(struct task_struct *child, long request,
         return ret;
 }
 
+asmlinkage unsigned long syscall_trace_enter(void)
+{
+        unsigned long ret = 0;
+        if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+            tracehook_report_syscall_entry(current_pt_regs()))
+                ret = -1UL;
+        return ret ?: current_pt_regs()->r0;
+}
+
 asmlinkage void
-syscall_trace(void)
+syscall_trace_leave(void)
 {
-        if (!test_thread_flag(TIF_SYSCALL_TRACE))
-                return;
-        if (!(current->ptrace & PT_PTRACED))
-                return;
-        /* The 0x80 provides a way for the tracing parent to distinguish
-           between a syscall stop and SIGTRAP delivery */
-        ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
-                                 ? 0x80 : 0));
-
-        /*
-         * This isn't the same as continuing with a signal, but it will do
-         * for normal use.  strace only continues with a signal if the
-         * stopping signal is not SIGTRAP.  -brl
-         */
-        if (current->exit_code) {
-                send_sig(current->exit_code, current, 1);
-                current->exit_code = 0;
-        }
+        if (test_thread_flag(TIF_SYSCALL_TRACE))
+                tracehook_report_syscall_exit(current_pt_regs(), 0);
 }