3 files changed, 17 insertions, 4 deletions

diff --git a/arch/m68k/kernel/entry.S b/arch/m68k/kernel/entry.S
index f28404d9a2bc..5b780826647c 100644
--- a/arch/m68k/kernel/entry.S
+++ b/arch/m68k/kernel/entry.S
@@ -424,7 +424,7 @@ resume:
 .data
 ALIGN
 sys_call_table:
-        .long sys_ni_syscall    /* 0  -  old "setup()" system call*/
+        .long sys_restart_syscall       /* 0 - old "setup()" system call, used for restarting */
         .long sys_exit
         .long sys_fork
         .long sys_read
diff --git a/arch/m68k/kernel/signal.c b/arch/m68k/kernel/signal.c
index f9af893cd289..de2d05ddd86d 100644
--- a/arch/m68k/kernel/signal.c
+++ b/arch/m68k/kernel/signal.c
@@ -326,6 +326,9 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __u
         struct sigcontext context;
         int err;
 
+        /* Always make any pending restarted system calls return -EINTR */
+        current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
         /* get previous context */
         if (copy_from_user(&context, usc, sizeof(context)))
                 goto badframe;
@@ -411,6 +414,9 @@ rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw,
         unsigned long usp;
         int err;
 
+        /* Always make any pending restarted system calls return -EINTR */
+        current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
         err = __get_user(temp, &uc->uc_mcontext.version);
         if (temp != MCONTEXT_VERSION)
                 goto badframe;
@@ -937,6 +943,15 @@ handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
                 regs->d0 = -EINTR;
                 break;
 
+        case -ERESTART_RESTARTBLOCK:
+                if (!has_handler) {
+                        regs->d0 = __NR_restart_syscall;
+                        regs->pc -= 2;
+                        break;
+                }
+                regs->d0 = -EINTR;
+                break;
+
         case -ERESTARTSYS:
                 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
                         regs->d0 = -EINTR;
diff --git a/include/asm-m68k/unistd.h b/include/asm-m68k/unistd.h
index 965abb8bc7ff..3c19027331fa 100644
--- a/include/asm-m68k/unistd.h
+++ b/include/asm-m68k/unistd.h
@@ -5,6 +5,7 @@
  * This file contains the system call numbers.
  */
 
+#define __NR_restart_syscall      0
 #define __NR_exit                 1
 #define __NR_fork                 2
 #define __NR_read                 3
@@ -359,9 +360,6 @@
 #define __ARCH_WANT_SYS_SIGPROCMASK
 #define __ARCH_WANT_SYS_RT_SIGACTION
 
-/* whitelist for checksyscalls */
-#define __IGNORE_restart_syscall
-
 /*
  * "Conditional" syscalls
  *