Commit Graph

5 Commits

Author SHA1 Message Date
Josh Poimboeuf 539012dcbd crypto: x86/sha256-ssse3 - Fix RBP usage
Using RBP as a temporary register breaks frame pointer convention and
breaks stack traces when unwinding from an interrupt in the crypto code.

Swap the usages of R12 and RBP.  Use R12 for the TBL register, and use
RBP to store the pre-aligned stack pointer.

Reported-by: Eric Biggers <ebiggers@google.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Eric Biggers <ebiggers@google.com>
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-09-20 17:42:37 +08:00
Denys Vlasenko e183914af0 crypto: x86 - make constants readonly, allow linker to merge them
A lot of asm-optimized routines in arch/x86/crypto/ keep its
constants in .data. This is wrong, they should be on .rodata.

Mnay of these constants are the same in different modules.
For example, 128-bit shuffle mask 0x000102030405060708090A0B0C0D0E0F
exists in at least half a dozen places.

There is a way to let linker merge them and use just one copy.
The rules are as follows: mergeable objects of different sizes
should not share sections. You can't put them all in one .rodata
section, they will lose "mergeability".

GCC puts its mergeable constants in ".rodata.cstSIZE" sections,
or ".rodata.cstSIZE.<object_name>" if -fdata-sections is used.
This patch does the same:

	.section .rodata.cst16.SHUF_MASK, "aM", @progbits, 16

It is important that all data in such section consists of
16-byte elements, not larger ones, and there are no implicit
use of one element from another.

When this is not the case, use non-mergeable section:

	.section .rodata[.VAR_NAME], "a", @progbits

This reduces .data by ~15 kbytes:

    text    data     bss     dec      hex filename
11097415 2705840 2630712 16433967  fac32f vmlinux-prev.o
11112095 2690672 2630712 16433479  fac147 vmlinux.o

Merged objects are visible in System.map:

ffffffff81a28810 r POLY
ffffffff81a28810 r POLY
ffffffff81a28820 r TWOONE
ffffffff81a28820 r TWOONE
ffffffff81a28830 r PSHUFFLE_BYTE_FLIP_MASK <- merged regardless of
ffffffff81a28830 r SHUF_MASK   <------------- the name difference
ffffffff81a28830 r SHUF_MASK
ffffffff81a28830 r SHUF_MASK
..
ffffffff81a28d00 r K512 <- merged three identical 640-byte tables
ffffffff81a28d00 r K512
ffffffff81a28d00 r K512

Use of object names in section name suffixes is not strictly necessary,
but might help if someday link stage will use garbage collection
to eliminate unused sections (ld --gc-sections).

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: Josh Poimboeuf <jpoimboe@redhat.com>
CC: Xiaodong Liu <xiaodong.liu@intel.com>
CC: Megha Dey <megha.dey@intel.com>
CC: linux-crypto@vger.kernel.org
CC: x86@kernel.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-01-23 22:50:29 +08:00
Ard Biesheuvel 1631030ae6 crypto: x86/sha256_ssse3 - move SHA-224/256 SSSE3 implementation to base layer
This removes all the boilerplate from the existing implementation,
and replaces it with calls into the base layer. It also changes the
prototypes of the core asm functions to be compatible with the base
prototype

  void (sha256_block_fn)(struct sha256_state *sst, u8 const *src, int blocks)

so that they can be passed to the base layer directly.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-04-10 21:39:47 +08:00
Jussi Kivilinna de614e561b crypto: sha256_ssse3 - fix stack corruption with SSSE3 and AVX implementations
The _XFER stack element size was set too small, 8 bytes, when it needs to be
16 bytes. As _XFER is the last stack element used by these implementations,
the 16 byte stores with 'movdqa' corrupt the stack where the value of register
%r12 is temporarily stored. As these implementations align the stack pointer
to 16 bytes, this corruption did not happen every time.

Patch corrects this issue.

Reported-by: Julian Wollrath <jwollrath@web.de>
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Tested-by: Julian Wollrath <jwollrath@web.de>
Acked-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-05-28 13:46:47 +08:00
Tim Chen 46d208a2bd crypto: sha256 - Optimized sha256 x86_64 assembly routine using Supplemental SSE3 instructions.
Provides SHA256 x86_64 assembly routine optimized with SSSE3 instructions.
Speedup of 40% or more has been measured over the generic implementation.

Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-04-03 09:06:31 +08:00