sh: invoke oom-killer from page fault

As explained in commit 1c0fe6e, we want to call the architecture independent
oom killer when getting an unexplained OOM from handle_mm_fault, rather than
simply killing current.

Cc: linux-sh@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/mm/fault_32.c

@@ -290,15 +290,10 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
  */
 out_of_memory:
 	up_read(&mm->mmap_sem);
-	if (is_global_init(current)) {
-		yield();
-		down_read(&mm->mmap_sem);
-		goto survive;
-	}
-	printk("VM: killing process %s\n", tsk->comm);
-	if (user_mode(regs))
-		do_group_exit(SIGKILL);
-	goto no_context;
+	if (!user_mode(regs))
+		goto no_context;
+	pagefault_out_of_memory();
+	return;
 
 do_sigbus:
 	up_read(&mm->mmap_sem);

arch/sh/mm/tlbflush_64.c

@@ -294,22 +294,11 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
  * us unable to handle the page fault gracefully.
  */
 out_of_memory:
-	if (is_global_init(current)) {
-		panic("INIT out of memory\n");
-		yield();
-		goto survive;
-	}
-	printk("fault:Out of memory\n");
 	up_read(&mm->mmap_sem);
-	if (is_global_init(current)) {
-		yield();
-		down_read(&mm->mmap_sem);
-		goto survive;
-	}
-	printk("VM: killing process %s\n", tsk->comm);
-	if (user_mode(regs))
-		do_group_exit(SIGKILL);
-	goto no_context;
+	if (!user_mode(regs))
+		goto no_context;
+	pagefault_out_of_memory();
+	return;
 
 do_sigbus:
 	printk("fault:Do sigbus\n");