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    SubjectRe: Clarification of allowed context for crypto routines
    Andrey Borzenkov <arvidjaar@mail.ru> wrote:
    >
    > As I can understand, user context requirement is due to potential for
    > setkey to sleep (although it appears, that currently the only module
    > that can sleep is shash which is calling kmalloc with GFP_KERNEL). Is it
    > correct?

    Yep.

    > But where is the difference between hard and softirq contexts? I fail to
    > see any technical reason for this requirement.

    The reasons are two-fold:

    1) Crypto operations are so slow in general that if you did them
    in hard IRQ context it would just be wrong;

    2) The highmem primitives we use are currently softirq only. We
    could make them work for hardirq as well, but because of 1) we
    didn't.

    Cheers,
    --
    Visit Openswan at http://www.openswan.org/
    Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
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