From: Marco Elver <elver@google.com>
Date: Tue, 16 Jun 2020 12:36:24 +0000 (+0200)
Subject: kcsan: Remove existing special atomic rules
X-Git-Tag: v5.10.7~2013^2~2^2~4
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7e766560e6e2c1cf2782f00e63c31564e4c9f0fe;p=platform%2Fkernel%2Flinux-rpi.git

kcsan: Remove existing special atomic rules

Remove existing special atomic rules from kcsan_is_atomic_special()
because they are no longer needed. Since we rely on the compiler
emitting instrumentation distinguishing volatile accesses, the rules
have become redundant.

Let's keep kcsan_is_atomic_special() around, so that we have an obvious
place to add special rules should the need arise in future.

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---

diff --git a/kernel/kcsan/atomic.h b/kernel/kcsan/atomic.h
index be9e625..75fe701 100644
--- a/kernel/kcsan/atomic.h
+++ b/kernel/kcsan/atomic.h
@@ -3,8 +3,7 @@
 #ifndef _KERNEL_KCSAN_ATOMIC_H
 #define _KERNEL_KCSAN_ATOMIC_H
 
-#include <linux/jiffies.h>
-#include <linux/sched.h>
+#include <linux/types.h>
 
 /*
  * Special rules for certain memory where concurrent conflicting accesses are
@@ -13,8 +12,7 @@
  */
 static bool kcsan_is_atomic_special(const volatile void *ptr)
 {
-	/* volatile globals that have been observed in data races. */
-	return ptr == &jiffies || ptr == &current->state;
+	return false;
 }
 
 #endif /* _KERNEL_KCSAN_ATOMIC_H */