From: Michael S. Tsirkin <mst@redhat.com>
Date: Tue, 6 Jan 2015 12:37:22 +0000 (+0200)
Subject: sh: fix put_user sparse errors
X-Git-Tag: firefly_0821_release~176^2~2280^2^2~17
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=66959ed0e4bd673f140f550fd3f7b3a70e8dbd24;p=firefly-linux-kernel-4.4.55.git

sh: fix put_user sparse errors

virtio wants to write bitwise types to userspace using put_user.
At the moment this triggers sparse errors, since the value is passed
through an integer.

For example:

	__le32 __user *p;
	__le32 x;
	put_user(x, p);

is safe, but currently triggers a sparse warning.

Fix that up using __force.

Note: this does not suppress any useful sparse checks since caller
assigns x to typeof(*p), which in turn forces all the necessary type
checks.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---

diff --git a/arch/sh/include/asm/uaccess_64.h b/arch/sh/include/asm/uaccess_64.h
index 2e07e0f40c6a..c01376c76b86 100644
--- a/arch/sh/include/asm/uaccess_64.h
+++ b/arch/sh/include/asm/uaccess_64.h
@@ -59,19 +59,19 @@ do {								\
 	switch (size) {						\
 	case 1:							\
 		retval = __put_user_asm_b((void *)&x,		\
-					  (long)ptr);		\
+					  (__force long)ptr);	\
 		break;						\
 	case 2:							\
 		retval = __put_user_asm_w((void *)&x,		\
-					  (long)ptr);		\
+					  (__force long)ptr);	\
 		break;						\
 	case 4:							\
 		retval = __put_user_asm_l((void *)&x,		\
-					  (long)ptr);		\
+					  (__force long)ptr);	\
 		break;						\
 	case 8:							\
 		retval = __put_user_asm_q((void *)&x,		\
-					  (long)ptr);		\
+					  (__force long)ptr);	\
 		break;						\
 	default:						\
 		__put_user_unknown();				\