Re: [PATCH/RFC 7/7] kernel: Force ACCESS_ONCE to work only on scalar types

[David Howells]

Christian Borntraeger <borntraeger@xxxxxxxxxx> wrote:

> +#define get_scalar_volatile_pointer(x) ({ \
> +	typeof(x) *__p = &(x); \
> +	volatile typeof(x) *__vp = __p; \
> +	(void)(long)*__p; __vp; })
> +#define ACCESS_ONCE(x) (*get_scalar_volatile_pointer(x))

Might this cause two loads from memory under some conditions?  Once for the
fourth line and once for the fifth?

(Apologies if this has already been discussed)

David
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