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/arm/include/asm/uaccess.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
index 4767eb9..74fcde7 100644
--- a/arch/arm/include/asm/uaccess.h
+++ b/arch/arm/include/asm/uaccess.h
@@ -413,14 +413,14 @@ do {
\
#ifndef __ARMEB__
#define __put_user_asm_half(x,__pu_addr,err) \
({ \
- unsigned long __temp = (unsigned long)(x); \
+ unsigned long __temp = (__force unsigned long)(x); \
__put_user_asm_byte(__temp, __pu_addr, err); \
__put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
})
#else
#define __put_user_asm_half(x,__pu_addr,err) \
({ \
- unsigned long __temp = (unsigned long)(x); \
+ unsigned long __temp = (__force unsigned long)(x); \
__put_user_asm_byte(__temp >> 8, __pu_addr, err); \
__put_user_asm_byte(__temp, __pu_addr + 1, err); \
})
--
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/
