Re: [PATCH] x86: Make variable_test_bit reference all of *addr

[hpanvin@xxxxxxxxx]

Memory clobbers are universal producers, not consumers.

Andi Kleen <andi@xxxxxxxxxxxxxx> wrote:

>"hpanvin@xxxxxxxxx" <hpa@xxxxxxxxx> writes:
>
>
>> This is concerning... the kernel relies heavily on asm volatile being
>a universal memory consumer.  If that is suddenly broken, we are f***
>in many, many, MANY places in the kernel all of a sudden!
>
>I don't think that's true. We generally add "memory" clobbers for this
>purpose. asm volatile just means "don't move" 
>
>Just this one doesn't have it for unknown reasons (someone
>overoptimizing?)
>
>-Andi
>
>-- 
>ak@xxxxxxxxxxxxxxx -- Speaking for myself only

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