commit 4635742d1cef5ee5f217f89310a8782ebb4e25dd
author Jason A. Donenfeld <Jason@zx2c4.com> Sun Oct 08 22:50:53 2017 +0200
committer Herbert Xu <herbert@gondor.apana.org.au> Thu Oct 12 22:51:16 2017 +0800
tree 21f54e060311132e108c05b48686ca3d2e3d4db0
parent b61907bb42409adf9b3120f741af7c57dd7e3db2

crypto: x86/chacha20 - satisfy stack validation 2.0

The new stack validator in objdump doesn't like directly assigning r11
to rsp, warning with something like:

warning: objtool: chacha20_4block_xor_ssse3()+0xa: unsupported stack pointer realignment
warning: objtool: chacha20_8block_xor_avx2()+0x6: unsupported stack pointer realignment

This fixes things up to use code similar to gcc's DRAP register, so that
objdump remains happy.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Fixes: baa41469a7b9 ("objtool: Implement stack validation 2.0")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>