target/linux/generic/backport-5.4/080-wireguard-0052-crypto-x86-curve25519-support-assemblers-with-no-adx.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: "Jason A. Donenfeld" <Jason@zx2c4.com>
   3 Date: Sun, 1 Mar 2020 22:52:35 +0800
   4 Subject: [PATCH] crypto: x86/curve25519 - support assemblers with no adx
   5  support
   6
   7 commit 1579f1bc3b753d17a44de3457d5c6f4a5b14c752 upstream.
   8
   9 Some older version of GAS do not support the ADX instructions, similarly
  10 to how they also don't support AVX and such. This commit adds the same
  11 build-time detection mechanisms we use for AVX and others for ADX, and
  12 then makes sure that the curve25519 library dispatcher calls the right
  13 functions.
  14
  15 Reported-by: Willy Tarreau <w@1wt.eu>
  16 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
  17 Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
  18 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
  19 ---
  20  arch/x86/Makefile           | 5 +++--
  21  arch/x86/crypto/Makefile    | 7 ++++++-
  22  include/crypto/curve25519.h | 6 ++++--
  23  3 files changed, 13 insertions(+), 5 deletions(-)
  24
  25 --- a/arch/x86/Makefile
  26 +++ b/arch/x86/Makefile
  27 @@ -197,9 +197,10 @@ avx2_instr :=$(call as-instr,vpbroadcast
  28  avx512_instr :=$(call as-instr,vpmovm2b %k1$(comma)%zmm5,-DCONFIG_AS_AVX512=1)
  29  sha1_ni_instr :=$(call as-instr,sha1msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA1_NI=1)
  30  sha256_ni_instr :=$(call as-instr,sha256msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA256_NI=1)
  31 +adx_instr := $(call as-instr,adox %r10$(comma)%r10,-DCONFIG_AS_ADX=1)
  32
  33 -KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr)
  34 -KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr)
  35 +KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr) $(adx_instr)
  36 +KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr) $(adx_instr)
  37
  38  KBUILD_LDFLAGS := -m elf_$(UTS_MACHINE)
  39
  40 --- a/arch/x86/crypto/Makefile
  41 +++ b/arch/x86/crypto/Makefile
  42 @@ -11,6 +11,7 @@ avx2_supported := $(call as-instr,vpgath
  43  avx512_supported :=$(call as-instr,vpmovm2b %k1$(comma)%zmm5,yes,no)
  44  sha1_ni_supported :=$(call as-instr,sha1msg1 %xmm0$(comma)%xmm1,yes,no)
  45  sha256_ni_supported :=$(call as-instr,sha256msg1 %xmm0$(comma)%xmm1,yes,no)
  46 +adx_supported := $(call as-instr,adox %r10$(comma)%r10,yes,no)
  47
  48  obj-$(CONFIG_CRYPTO_GLUE_HELPER_X86) += glue_helper.o
  49
  50 @@ -39,7 +40,11 @@ obj-$(CONFIG_CRYPTO_AEGIS128_AESNI_SSE2)
  51
  52  obj-$(CONFIG_CRYPTO_NHPOLY1305_SSE2) += nhpoly1305-sse2.o
  53  obj-$(CONFIG_CRYPTO_NHPOLY1305_AVX2) += nhpoly1305-avx2.o
  54 -obj-$(CONFIG_CRYPTO_CURVE25519_X86) += curve25519-x86_64.o
  55 +
  56 +# These modules require the assembler to support ADX.
  57 +ifeq ($(adx_supported),yes)
  58 +       obj-$(CONFIG_CRYPTO_CURVE25519_X86) += curve25519-x86_64.o
  59 +endif
  60
  61  # These modules require assembler to support AVX.
  62  ifeq ($(avx_supported),yes)
  63 --- a/include/crypto/curve25519.h
  64 +++ b/include/crypto/curve25519.h
  65 @@ -33,7 +33,8 @@ bool __must_check curve25519(u8 mypublic
  66                              const u8 secret[CURVE25519_KEY_SIZE],
  67                              const u8 basepoint[CURVE25519_KEY_SIZE])
  68  {
  69 -       if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_CURVE25519))
  70 +       if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_CURVE25519) &&
  71 +           (!IS_ENABLED(CONFIG_CRYPTO_CURVE25519_X86) || IS_ENABLED(CONFIG_AS_ADX)))
  72                 curve25519_arch(mypublic, secret, basepoint);
  73         else
  74                 curve25519_generic(mypublic, secret, basepoint);
  75 @@ -49,7 +50,8 @@ __must_check curve25519_generate_public(
  76                                     CURVE25519_KEY_SIZE)))
  77                 return false;
  78
  79 -       if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_CURVE25519))
  80 +       if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_CURVE25519) &&
  81 +           (!IS_ENABLED(CONFIG_CRYPTO_CURVE25519_X86) || IS_ENABLED(CONFIG_AS_ADX)))
  82                 curve25519_base_arch(pub, secret);
  83         else
  84                 curve25519_generic(pub, secret, curve25519_base_point);