[PATCH v2 0/8] x86: Remove cpu_has_xfeatures() and add AVX-512 xor_gen()

[Eric Biggers]

This series consolidates and cleans up how the kernel handles CPU
feature flags for AVX and AVX-512 when the underlying OS or hypervisor
(if any) doesn't enable the required xstate features in XCR0.

Specifically, it makes the checks for xstate features be done in a
single place at boot time for both UML and native x86, instead of
everywhere kernel code wants to check for AVX or AVX-512 support.

Patch 8 then adds an AVX-512 optimized implementation of xor_gen() for
RAID, which had been blocked on confusion around cpu_has_xfeatures() and
its lack of implementation on UML.

Changed in v2:

  - Made x86 clear the AVX* bits if FPU or XSAVE features are missing.
  - Updated comment in x86 arch_xor_init().
  - Updated commit message for the UML commit to clarify that checking
    XCR0 is standard practice in userspace

Eric Biggers (8):
  x86/fpu: Check for missing AVX and AVX-512 xstate bits
  um: Check for missing AVX and AVX-512 xstate bits
  crypto: x86 - Stop using cpu_has_xfeatures()
  lib/crypto: x86: Stop using cpu_has_xfeatures()
  lib/crc: x86: Stop using cpu_has_xfeatures()
  x86/fpu: Remove cpu_has_xfeatures()
  lib/raid/xor: x86: Remove redundant X86_FEATURE_OSXSAVE check
  lib/raid/xor: x86: Add AVX-512 optimized xor_gen()

 arch/um/kernel/um_arch.c                   |  78 ++++++++++++-
 arch/x86/crypto/aegis128-aesni-glue.c      |   3 +-
 arch/x86/crypto/aesni-intel_glue.c         |   7 +-
 arch/x86/crypto/aria_aesni_avx2_glue.c     |  11 +-
 arch/x86/crypto/aria_aesni_avx_glue.c      |  11 +-
 arch/x86/crypto/aria_gfni_avx512_glue.c    |  11 +-
 arch/x86/crypto/camellia_aesni_avx2_glue.c |  11 +-
 arch/x86/crypto/camellia_aesni_avx_glue.c  |  11 +-
 arch/x86/crypto/cast5_avx_glue.c           |   7 +-
 arch/x86/crypto/cast6_avx_glue.c           |   7 +-
 arch/x86/crypto/serpent_avx2_glue.c        |   9 +-
 arch/x86/crypto/serpent_avx_glue.c         |   7 +-
 arch/x86/crypto/sm4_aesni_avx2_glue.c      |  11 +-
 arch/x86/crypto/sm4_aesni_avx_glue.c       |  11 +-
 arch/x86/crypto/twofish_avx_glue.c         |   6 +-
 arch/x86/include/asm/fpu/api.h             |   9 --
 arch/x86/kernel/fpu/xstate.c               |  65 ++++-------
 lib/crc/x86/crc-pclmul-template.h          |   6 +-
 lib/crypto/x86/blake2s.h                   |   4 +-
 lib/crypto/x86/chacha.h                    |   3 +-
 lib/crypto/x86/nh.h                        |   4 +-
 lib/crypto/x86/poly1305.h                  |   7 +-
 lib/crypto/x86/sha1.h                      |   4 +-
 lib/crypto/x86/sha256.h                    |   4 +-
 lib/crypto/x86/sha512.h                    |   3 +-
 lib/crypto/x86/sm3.h                       |   3 +-
 lib/raid/xor/Makefile                      |   2 +-
 lib/raid/xor/x86/xor-avx512.c              | 121 +++++++++++++++++++++
 lib/raid/xor/x86/xor_arch.h                |  31 ++++--
 29 files changed, 273 insertions(+), 194 deletions(-)
 create mode 100644 lib/raid/xor/x86/xor-avx512.c


base-commit: f5098b6bae761e346ebcd9da7f95622c04733cff
-- 
2.55.0