From 723cada63f8d8ce8185fd628bbb5be49708a202f Mon Sep 17 00:00:00 2001
From: Roland McGrath <roland@redhat.com>
Date: Fri, 25 Jul 2008 19:45:50 -0700
Subject: [PATCH] --- yaml --- r: 106213 b: refs/heads/master c:
 fa8e26ccd485216fc45c8c2dd1ec3b7ef1a0a2f8 h: refs/heads/master i:   106211:
 e579f675f7e7d02712b8f964d025a356c7c9f040 v: v3

---
 [refs]                          |  2 +-
 trunk/include/linux/tracehook.h | 15 +++++++++++++++
 trunk/mm/nommu.c                |  4 ++--
 3 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 9f67c5f6e0f9..3cc03f7b7af7 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 0d094efeb1e98010c6b99923f1eb7e17bf1e3a74
+refs/heads/master: fa8e26ccd485216fc45c8c2dd1ec3b7ef1a0a2f8
diff --git a/trunk/include/linux/tracehook.h b/trunk/include/linux/tracehook.h
index 6468ca0fe69b..e113e09b0341 100644
--- a/trunk/include/linux/tracehook.h
+++ b/trunk/include/linux/tracehook.h
@@ -51,6 +51,21 @@
 #include <linux/security.h>
 struct linux_binprm;
 
+/**
+ * tracehook_expect_breakpoints - guess if task memory might be touched
+ * @task:		current task, making a new mapping
+ *
+ * Return nonzero if @task is expected to want breakpoint insertion in
+ * its memory at some point.  A zero return is no guarantee it won't
+ * be done, but this is a hint that it's known to be likely.
+ *
+ * May be called with @task->mm->mmap_sem held for writing.
+ */
+static inline int tracehook_expect_breakpoints(struct task_struct *task)
+{
+	return (task_ptrace(task) & PT_PTRACED) != 0;
+}
+
 /**
  * tracehook_unsafe_exec - check for exec declared unsafe due to tracing
  * @task:		current task doing exec
diff --git a/trunk/mm/nommu.c b/trunk/mm/nommu.c
index 4462b6a3fcb9..5edccd9c9218 100644
--- a/trunk/mm/nommu.c
+++ b/trunk/mm/nommu.c
@@ -22,7 +22,7 @@
 #include <linux/pagemap.h>
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
-#include <linux/ptrace.h>
+#include <linux/tracehook.h>
 #include <linux/blkdev.h>
 #include <linux/backing-dev.h>
 #include <linux/mount.h>
@@ -745,7 +745,7 @@ static unsigned long determine_vm_flags(struct file *file,
 	 * it's being traced - otherwise breakpoints set in it may interfere
 	 * with another untraced process
 	 */
-	if ((flags & MAP_PRIVATE) && (current->ptrace & PT_PTRACED))
+	if ((flags & MAP_PRIVATE) && tracehook_expect_breakpoints(current))
 		vm_flags &= ~VM_MAYSHARE;
 
 	return vm_flags;