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.
This also fixes warnings due to writing a pointer out to
userland.
Note: this does not suppress any useful sparse checks since callers
do a cast (__typeof__(*(ptr))) (x) which in turn forces all the
necessary type checks.
Suggested-by: James Hogan <james.hogan@xxxxxxxxxx>
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
---
arch/metag/include/asm/uaccess.h | 21 +++++++++++++--------
1 file changed, 13 insertions(+), 8 deletions(-)
diff --git a/arch/metag/include/asm/uaccess.h b/arch/metag/include/asm/uaccess.h
index c314b45..9627c19 100644
--- a/arch/metag/include/asm/uaccess.h
+++ b/arch/metag/include/asm/uaccess.h
@@ -107,18 +107,23 @@ extern long __put_user_asm_w(unsigned int x, void __user *addr);
extern long __put_user_asm_d(unsigned int x, void __user *addr);
extern long __put_user_asm_l(unsigned long long x, void __user *addr);
-#define __put_user_size(x, ptr, size, retval) \
-do { \
- retval = 0; \
- switch (size) { \
+#define __put_user_size(x, ptr, size, retval) \
+do { \
+ retval = 0; \
+ switch (size) { \
case 1: \
- retval = __put_user_asm_b((unsigned int)x, ptr); break; \
+ retval = __put_user_asm_b((__force unsigned int)x, ptr);\
+ break; \
case 2: \
- retval = __put_user_asm_w((unsigned int)x, ptr); break; \
+ retval = __put_user_asm_w((__force unsigned int)x, ptr);\
+ break; \
case 4: \
- retval = __put_user_asm_d((unsigned int)x, ptr); break; \
+ retval = __put_user_asm_d((__force unsigned int)x, ptr);\
+ break; \
case 8: \
- retval = __put_user_asm_l((unsigned long long)x, ptr); break; \
+ retval = __put_user_asm_l((__force unsigned long long)x,\
+ ptr); \
+ break; \
default: \
__put_user_bad(); \
} \
--
MST
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