crypto: xts: regression in 4.10

[Nicolas Porcel <nicolasporcel06@gmail.com>]

Hello,

I am using aes-xts-plain64 with LUKS headers to crypt the root. In 4.10,
the partition cannot be opened and I have the following errors when
booting:

    device-mapper: table: 253:0: crypt: Error allocating crypto tfm
    device-mapper: ioctl: error adding target to table
    device-mapper: reload ioctl on  failed: No such file or directory
    Failed to setup dm-crypt key mapping for device /dev/mmcblk0p2
    Check that the kernel supports aes-xts-plain64 cipher (check syslog for more info)

I found that this commit is responsible for the regression (reverting it
solves the problem):

> commit f1c131b45410a202eb45cc55980a7a9e4e4b4f40
> Author: Herbert Xu <herbert@gondor.apana.org.au>
> Date:   Tue Nov 22 20:08:19 2016 +0800
> 
>     crypto: xts - Convert to skcipher

Some precision: I am using the vanilla kernel source for 4.10. The aes,
xts and dm-crypt modules are directly compiled in the kernel and not as
modules. I also had the same problem with kernel 4.10-rc*.

Is it a known issue? I found 1 related email with no answer on the
dm-crypt mailing. If this is a regression, I can start digging, although
any guidance would be greatly appreciated.

Thank you in advance,

Best regards,

-- 
Nicolas Porcel