Re: [PATCH 13/18] powerpc/uaccess: fix sparse errors

From: Benjamin Herrenschmidt
Date: Sun Dec 14 2014 - 19:05:46 EST


On Sun, 2014-12-14 at 18:52 +0200, Michael S. Tsirkin wrote:
> virtio wants to read bitwise types from userspace using get_user. At the
> moment this triggers sparse errors, since the value is passed through an
> integer.
>
> Fix that up using __force.

You mean bitfields ? Argh ... we should just remove them from the
compiler and be done with it :-(

Ben.

> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
> ---
> arch/powerpc/include/asm/uaccess.h | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
> index 9485b43..a0c071d 100644
> --- a/arch/powerpc/include/asm/uaccess.h
> +++ b/arch/powerpc/include/asm/uaccess.h
> @@ -284,7 +284,7 @@ do { \
> if (!is_kernel_addr((unsigned long)__gu_addr)) \
> might_fault(); \
> __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
> - (x) = (__typeof__(*(ptr)))__gu_val; \
> + (x) = (__force __typeof__(*(ptr)))__gu_val; \
> __gu_err; \
> })
> #endif /* __powerpc64__ */
> @@ -297,7 +297,7 @@ do { \
> might_fault(); \
> if (access_ok(VERIFY_READ, __gu_addr, (size))) \
> __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
> - (x) = (__typeof__(*(ptr)))__gu_val; \
> + (x) = (__force __typeof__(*(ptr)))__gu_val; \
> __gu_err; \
> })
>
> @@ -308,7 +308,7 @@ do { \
> const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
> __chk_user_ptr(ptr); \
> __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
> - (x) = (__typeof__(*(ptr)))__gu_val; \
> + (x) = (__force __typeof__(*(ptr)))__gu_val; \
> __gu_err; \
> })
>


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