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

Pull third pile of signal handling patches from Al Viro:
 "This time it's mostly helpers and conversions to them; there's a lot
  of stuff remaining in the tree, but that'll either go in -rc2
  (isolated bug fixes, ideally via arch maintainers' trees) or will sit
  there until the next cycle."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  x86: get rid of calling do_notify_resume() when returning to kernel mode
  blackfin: check __get_user() return value
  whack-a-mole with TIF_FREEZE
  FRV: Optimise the system call exit path in entry.S [ver #2]
  FRV: Shrink TIF_WORK_MASK [ver #2]
  FRV: Prevent syscall exit tracing and notify_resume at end of kernel exceptions
  new helper: signal_delivered()
  powerpc: get rid of restore_sigmask()
  most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set
  set_restore_sigmask() is never called without SIGPENDING (and never should be)
  TIF_RESTORE_SIGMASK can be set only when TIF_SIGPENDING is set
  don't call try_to_freeze() from do_signal()
  pull clearing RESTORE_SIGMASK into block_sigmask()
  sh64: failure to build sigframe != signal without handler
  openrisc: tracehook_signal_handler() is supposed to be called on success
  new helper: sigmask_to_save()
  new helper: restore_saved_sigmask()
  new helpers: {clear,test,test_and_clear}_restore_sigmask()
  HAVE_RESTORE_SIGMASK is defined on all architectures now

4 files changed, 14 insertions, 41 deletions

diff --git a/arch/parisc/include/asm/thread_info.h b/arch/parisc/include/asm/thread_info.h
index 83ae7dd4d99e..22b4726dee49 100644
--- a/arch/parisc/include/asm/thread_info.h
+++ b/arch/parisc/include/asm/thread_info.h
@@ -74,7 +74,7 @@ struct thread_info {
 #define _TIF_BLOCKSTEP          (1 << TIF_BLOCKSTEP)
 
 #define _TIF_USER_WORK_MASK     (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | \
-                                 _TIF_NEED_RESCHED | _TIF_RESTORE_SIGMASK)
+                                 _TIF_NEED_RESCHED)
 
 #endif /* __KERNEL__ */
 
diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S
index c7fbc96472f3..18670a078849 100644
--- a/arch/parisc/kernel/entry.S
+++ b/arch/parisc/kernel/entry.S
@@ -924,7 +924,7 @@ intr_check_sig:
         /* As above */
         mfctl   %cr30,%r1
         LDREG   TI_FLAGS(%r1),%r19
-        ldi     (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK|_TIF_NOTIFY_RESUME), %r20
+        ldi     (_TIF_SIGPENDING|_TIF_NOTIFY_RESUME), %r20
         and,COND(<>)    %r19, %r20, %r0
         b,n     intr_restore    /* skip past if we've nothing to do */
 
@@ -2032,7 +2032,7 @@ syscall_check_resched:
         .import do_signal,code
 syscall_check_sig:
         LDREG   TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19
-        ldi     (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK|_TIF_NOTIFY_RESUME), %r26
+        ldi     (_TIF_SIGPENDING|_TIF_NOTIFY_RESUME), %r26
         and,COND(<>)    %r19, %r26, %r0
         b,n     syscall_restore /* skip past if we've nothing to do */
 
diff --git a/arch/parisc/kernel/signal.c b/arch/parisc/kernel/signal.c
index e7a7cd3e1120..594459bde14e 100644
--- a/arch/parisc/kernel/signal.c
+++ b/arch/parisc/kernel/signal.c
@@ -48,9 +48,6 @@
 #define DBG(LEVEL, ...)
 #endif
         
-
-#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
-
 /* gcc will complain if a pointer is cast to an integer of different
  * size.  If you really need to do this (and we do for an ELF32 user
  * application in an ELF64 kernel) then you have to do a cast to an
@@ -131,7 +128,6 @@ sys_rt_sigreturn(struct pt_regs *regs, int in_syscall)
                         goto give_sigsegv;
         }
                 
-        sigdelsetmask(&set, ~_BLOCKABLE);
         set_current_blocked(&set);
 
         /* Good thing we saved the old gr[30], eh? */
@@ -443,8 +439,9 @@ give_sigsegv:
 
 static long
 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
-                sigset_t *oldset, struct pt_regs *regs, int in_syscall)
+                struct pt_regs *regs, int in_syscall)
 {
+        sigset_t *oldset = sigmask_to_save();
         DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n",
                sig, ka, info, oldset, regs);
         
@@ -452,12 +449,13 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
         if (!setup_rt_frame(sig, ka, info, oldset, regs, in_syscall))
                 return 0;
 
-        block_sigmask(ka, sig);
-
-        tracehook_signal_handler(sig, info, ka, regs, 
+        signal_delivered(sig, info, ka, regs, 
                 test_thread_flag(TIF_SINGLESTEP) ||
                 test_thread_flag(TIF_BLOCKSTEP));
 
+        DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
+                regs->gr[28]);
+
         return 1;
 }
 
@@ -568,28 +566,17 @@ do_signal(struct pt_regs *regs, long in_syscall)
         siginfo_t info;
         struct k_sigaction ka;
         int signr;
-        sigset_t *oldset;
 
-        DBG(1,"\ndo_signal: oldset=0x%p, regs=0x%p, sr7 %#lx, in_syscall=%d\n",
-               oldset, regs, regs->sr[7], in_syscall);
+        DBG(1,"\ndo_signal: regs=0x%p, sr7 %#lx, in_syscall=%d\n",
+               regs, regs->sr[7], in_syscall);
 
         /* Everyone else checks to see if they are in kernel mode at
            this point and exits if that's the case.  I'm not sure why
            we would be called in that case, but for some reason we
            are. */
 
-        if (test_thread_flag(TIF_RESTORE_SIGMASK))
-                oldset = &current->saved_sigmask;
-        else
-                oldset = &current->blocked;
-
-        DBG(1,"do_signal: oldset %08lx / %08lx\n", 
-                oldset->sig[0], oldset->sig[1]);
-
-
         /* May need to force signal if handle_signal failed to deliver */
         while (1) {
-          
                 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
                 DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]); 
         
@@ -603,14 +590,8 @@ do_signal(struct pt_regs *regs, long in_syscall)
                 /* Whee!  Actually deliver the signal.  If the
                    delivery failed, we need to continue to iterate in
                    this loop so we can deliver the SIGSEGV... */
-                if (handle_signal(signr, &info, &ka, oldset,
-                                  regs, in_syscall)) {
-                        DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
-                                regs->gr[28]);
-                        if (test_thread_flag(TIF_RESTORE_SIGMASK))
-                                clear_thread_flag(TIF_RESTORE_SIGMASK);
+                if (handle_signal(signr, &info, &ka, regs, in_syscall))
                         return;
-                }
         }
         /* end of while(1) looping forever if we can't force a signal */
 
@@ -621,18 +602,12 @@ do_signal(struct pt_regs *regs, long in_syscall)
         DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n", 
                 regs->gr[28]);
 
-        if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
-                clear_thread_flag(TIF_RESTORE_SIGMASK);
-                sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
-        }
-
-        return;
+        restore_saved_sigmask();
 }
 
 void do_notify_resume(struct pt_regs *regs, long in_syscall)
 {
-        if (test_thread_flag(TIF_SIGPENDING) ||
-            test_thread_flag(TIF_RESTORE_SIGMASK))
+        if (test_thread_flag(TIF_SIGPENDING))
                 do_signal(regs, in_syscall);
 
         if (test_thread_flag(TIF_NOTIFY_RESUME)) {
diff --git a/arch/parisc/kernel/signal32.c b/arch/parisc/kernel/signal32.c
index e14132430762..fd49aeda9eb8 100644
--- a/arch/parisc/kernel/signal32.c
+++ b/arch/parisc/kernel/signal32.c
@@ -47,8 +47,6 @@
 #define DBG(LEVEL, ...)
 #endif
 
-#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
-
 inline void
 sigset_32to64(sigset_t *s64, compat_sigset_t *s32)
 {