On Thu, Nov 06, 2014 at 03:26:33PM +0100, Maxime Ripard wrote:

But you still haven't explain why the driver, while it doesn't handle
the user space buffer at any time, should be worried that the data the
framework has given him are actually mapped.

Encryption is used by IPsec and SKBs can be allocated in highmem.
algif also exposes all ciphers to user-space memory which can also
be in highmem.

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