X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=include%2Flinux%2Fpreempt.h;h=e86bf010fbc45ebe20e76d106812401f13c37d8b;hb=9d6c5babc04522ff85b550f14563970279ab8f90;hp=58969b2a8a8292deb33a215006eade8659764d6d;hpb=219f358e0ba9a98640341e030533089860af1cc6;p=pandora-kernel.git

diff --git a/include/linux/preempt.h b/include/linux/preempt.h
index 58969b2a8a82..e86bf010fbc4 100644
--- a/include/linux/preempt.h
+++ b/include/linux/preempt.h
@@ -91,13 +91,19 @@ do { \
 
 #else /* !CONFIG_PREEMPT_COUNT */
 
-#define preempt_disable()		do { } while (0)
-#define preempt_enable_no_resched()	do { } while (0)
-#define preempt_enable()		do { } while (0)
+/*
+ * Even if we don't have any preemption, we need preempt disable/enable
+ * to be barriers, so that we don't have things like get_user/put_user
+ * that can cause faults and scheduling migrate into our preempt-protected
+ * region.
+ */
+#define preempt_disable()		barrier()
+#define preempt_enable_no_resched()	barrier()
+#define preempt_enable()		barrier()
 
-#define preempt_disable_notrace()		do { } while (0)
-#define preempt_enable_no_resched_notrace()	do { } while (0)
-#define preempt_enable_notrace()		do { } while (0)
+#define preempt_disable_notrace()		barrier()
+#define preempt_enable_no_resched_notrace()	barrier()
+#define preempt_enable_notrace()		barrier()
 
 #endif /* CONFIG_PREEMPT_COUNT */