tree:   https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master
head:   b40fa82cd6138350f723aa47b37e3e3e80906b40
commit: 148b974deea927f5dbb6c468af2707b488bfa2de [130/134] crypto: aes-generic - build with -Os on gcc-7+
config: powerpc-linkstation_defconfig (attached as .config)
compiler: powerpc-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        git checkout 148b974deea927f5dbb6c468af2707b488bfa2de
        # save the attached .config to linux build tree
        make.cross ARCH=powerpc 

All errors (new ones prefixed by >>):

   crypto/aes_generic.o: In function `crypto_aes_set_key':
>> aes_generic.c:(.text+0x4e0): undefined reference to `_restgpr_31_x'

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0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation