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 <[email protected]>
---
 arch/sh/include/asm/uaccess_64.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/sh/include/asm/uaccess_64.h b/arch/sh/include/asm/uaccess_64.h
index 2e07e0f..c01376c 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();                           \
-- 
MST

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to