Pull x86 core updates from Borislav Petkov:

 - Add the call depth tracking mitigation for Retbleed which has been
   long in the making. It is a lighterweight software-only fix for
   Skylake-based cores where enabling IBRS is a big hammer and causes a
   significant performance impact.

   What it basically does is, it aligns all kernel functions to 16 bytes
   boundary and adds a 16-byte padding before the function, objtool
   collects all functions' locations and when the mitigation gets
   applied, it patches a call accounting thunk which is used to track
   the call depth of the stack at any time.

   When that call depth reaches a magical, microarchitecture-specific
   value for the Return Stack Buffer, the code stuffs that RSB and
   avoids its underflow which could otherwise lead to the Intel variant
   of Retbleed.

   This software-only solution brings a lot of the lost performance
   back, as benchmarks suggest:

       https://lore.kernel.org/all/20220915111039.092790446@infradead.org/

   That page above also contains a lot more detailed explanation of the
   whole mechanism

 - Implement a new control flow integrity scheme called FineIBT which is
   based on the software kCFI implementation and uses hardware IBT
   support where present to annotate and track indirect branches using a
   hash to validate them

 - Other misc fixes and cleanups

* tag 'x86_core_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (80 commits)
  x86/paravirt: Use common macro for creating simple asm paravirt functions
  x86/paravirt: Remove clobber bitmask from .parainstructions
  x86/debug: Include percpu.h in debugreg.h to get DECLARE_PER_CPU() et al
  x86/cpufeatures: Move X86_FEATURE_CALL_DEPTH from bit 18 to bit 19 of word 11, to leave space for WIP X86_FEATURE_SGX_EDECCSSA bit
  x86/Kconfig: Enable kernel IBT by default
  x86,pm: Force out-of-line memcpy()
  objtool: Fix weak hole vs prefix symbol
  objtool: Optimize elf_dirty_reloc_sym()
  x86/cfi: Add boot time hash randomization
  x86/cfi: Boot time selection of CFI scheme
  x86/ibt: Implement FineIBT
  objtool: Add --cfi to generate the .cfi_sites section
  x86: Add prefix symbols for function padding
  objtool: Add option to generate prefix symbols
  objtool: Avoid O(bloody terrible) behaviour -- an ode to libelf
  objtool: Slice up elf_create_section_symbol()
  kallsyms: Revert "Take callthunks into account"
  x86: Unconfuse CONFIG_ and X86_FEATURE_ namespaces
  x86/retpoline: Fix crash printing warning
  x86/paravirt: Fix a !PARAVIRT build warning
  ...

The helper crypto_tfm_ctx is only used by the Crypto API algorithm
code and should really be in algapi.h.  However, for historical
reasons many files relied on it to be in crypto.h.  This patch
changes those files to use algapi.h instead in prepartion for a
move.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

curve25519-x86_64.c fails to build when CONFIG_GCOV_KERNEL is enabled.
The error is "inline assembly requires more registers than available"
thrown from the `fsqr()` function. Therefore, excluding this file from
GCOV profiling until this issue is resolved. Thereby allowing
CONFIG_GCOV_PROFILE_ALL to be enabled for x86.

Signed-off-by: Joe Fradley <joefradley@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

sm4_aesni_avx_ctr_enc_blk8(), sm4_aesni_avx_cbc_dec_blk8(),
sm4_aesni_avx_cfb_dec_blk8(), sm4_aesni_avx2_ctr_enc_blk16(),
sm4_aesni_avx2_cbc_dec_blk16(), and sm4_aesni_avx2_cfb_dec_blk16() are
called via indirect function calls.  Therefore they need to use
SYM_TYPED_FUNC_START instead of SYM_FUNC_START to cause their type
hashes to be emitted when the kernel is built with CONFIG_CFI_CLANG=y.
Otherwise, the code crashes with a CFI failure.

(Or at least that should be the case.  For some reason the CFI checks in
sm4_avx_cbc_decrypt(), sm4_avx_cfb_decrypt(), and sm4_avx_ctr_crypt()
are not always being generated, using current tip-of-tree clang.
Anyway, this patch is a good idea anyway.)

Fixes: ccace936eec7 ("x86: Add types to indirectly called assembly functions")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

sm3_transform_avx() is called via indirect function calls.  Therefore it
needs to use SYM_TYPED_FUNC_START instead of SYM_FUNC_START to cause its
type hash to be emitted when the kernel is built with
CONFIG_CFI_CLANG=y.  Otherwise, the code crashes with a CFI failure (if
the compiler didn't happen to optimize out the indirect call).

Fixes: ccace936eec7 ("x86: Add types to indirectly called assembly functions")
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

sha512_transform_ssse3(), sha512_transform_avx(), and
sha512_transform_rorx() are called via indirect function calls.
Therefore they need to use SYM_TYPED_FUNC_START instead of
SYM_FUNC_START to cause their type hashes to be emitted when the kernel
is built with CONFIG_CFI_CLANG=y.  Otherwise, the code crashes with a
CFI failure (if the compiler didn't happen to optimize out the indirect
calls).

Fixes: ccace936eec7 ("x86: Add types to indirectly called assembly functions")
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

sha256_transform_ssse3(), sha256_transform_avx(),
sha256_transform_rorx(), and sha256_ni_transform() are called via
indirect function calls.  Therefore they need to use
SYM_TYPED_FUNC_START instead of SYM_FUNC_START to cause their type
hashes to be emitted when the kernel is built with CONFIG_CFI_CLANG=y.
Otherwise, the code crashes with a CFI failure (if the compiler didn't
happen to optimize out the indirect calls).

Fixes: ccace936eec7 ("x86: Add types to indirectly called assembly functions")
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

sha1_transform_ssse3(), sha1_transform_avx(), and sha1_ni_transform()
(but not sha1_transform_avx2()) are called via indirect function calls.
Therefore they need to use SYM_TYPED_FUNC_START instead of
SYM_FUNC_START to cause their type hashes to be emitted when the kernel
is built with CONFIG_CFI_CLANG=y.  Otherwise, the code crashes with a
CFI failure (if the compiler didn't happen to optimize out the indirect
calls).

Fixes: ccace936eec7 ("x86: Add types to indirectly called assembly functions")
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Since the CFI implementation now supports indirect calls to assembly
functions, take advantage of that rather than use wrapper functions.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

aria_aesni_avx_encrypt_16way(), aria_aesni_avx_decrypt_16way(),
aria_aesni_avx_ctr_crypt_16way(), aria_aesni_avx_gfni_encrypt_16way(),
aria_aesni_avx_gfni_decrypt_16way(), and
aria_aesni_avx_gfni_ctr_crypt_16way() are called via indirect function
calls.  Therefore they need to use SYM_TYPED_FUNC_START instead of
SYM_FUNC_START to cause their type hashes to be emitted when the kernel
is built with CONFIG_CFI_CLANG=y.  Otherwise, the code crashes with a
CFI failure.

Fixes: ccace936eec7 ("x86: Add types to indirectly called assembly functions")
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Cc: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>