Al Viro [off-list ref] wrote:

       * shoved into scatterlist, which gets fed into crypto/*.c machinery.
No way for a pipe_buffer stuff to get there, fortunately, because I would
be very surprised if it works correctly with compound pages and large
ranges in those.

FWIW the crypto API has always been supposed to handle SG entries
that cross page boundaries.  There were a couple of bugs in this
area but AFAIK they've all been fixed.

Of course I cannot guarantee that every crypto driver also handles
it correctly, but at least we have a few test vectors which test
the page-crossing case specifically.

Cheers,
-- 
Email: Herbert Xu [off-list ref]
Home Page: http://gondor.apana.org.au/~herbert/
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