8 Commits

Author SHA1 Message Date
Robin Murphy
0e51f2e288 arm64: lib: Import latest memcpy()/memmove() implementation
Import the latest implementation of memcpy(), based on the
upstream code of string/aarch64/memcpy.S at commit afd6244 from
https://github.com/ARM-software/optimized-routines, and subsuming
memmove() in the process.

Note that for simplicity Arm have chosen to contribute this code
to Linux under GPLv2 rather than the original MIT license.

Note also that the needs of the usercopy routines vs. regular memcpy()
have now diverged so far that we abandon the shared template idea
and the damage which that incurred to the tuning of LDP/STP loops.
We'll be back to tackle those routines separately in future.

Link: https://lore.kernel.org/r/3c953af43506581b2422f61952261e76949ba711.1622128527.git.robin.murphy@arm.com
Change-Id: I78b4d7bf65b1a4eebf509b087d0120b0f99e51c4
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Richard Raya <rdxzv.dev@gmail.com>
2024-12-18 23:08:21 -03:00
Richard Raya
866c561aa2 arm64: lib: Checkout memcpy from linux-next
ec9d78070de986ecf581ea204fd322af4d2477ec

Change-Id: Ie586b44d9c1e8c8e7b0c005eb706b2932013cb40
Signed-off-by: Richard Raya <rdxzv.dev@gmail.com>
2024-12-13 19:47:22 -03:00
Fangrui Song
5b2db14d1f arm64: Change .weak to SYM_FUNC_START_WEAK_PI for arch/arm64/lib/mem*.S
commit ec9d78070de986ecf581ea204fd322af4d2477ec upstream.

Commit 39d114ddc682 ("arm64: add KASAN support") added .weak directives to
arch/arm64/lib/mem*.S instead of changing the existing SYM_FUNC_START_PI
macros. This can lead to the assembly snippet `.weak memcpy ... .globl
memcpy` which will produce a STB_WEAK memcpy with GNU as but STB_GLOBAL
memcpy with LLVM's integrated assembler before LLVM 12. LLVM 12 (since
https://reviews.llvm.org/D90108) will error on such an overridden symbol
binding.

Use the appropriate SYM_FUNC_START_WEAK_PI instead.

Fixes: 39d114ddc682 ("arm64: add KASAN support")
Reported-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201029181951.1866093-1-maskray@google.com
Signed-off-by: Will Deacon <will@kernel.org>
[nd: backport to adjust for missing:
  commit 3ac0f4526dfb ("arm64: lib: Use modern annotations for assembly functions")
  commit 35e61c77ef38 ("arm64: asm: Add new-style position independent function annotations")]
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: I63c34385861c5a84cdf332a912f5ee53dedac3bd
2023-11-14 20:23:13 -03:00
Andrey Ryabinin
39d114ddc6 arm64: add KASAN support
This patch adds arch specific code for kernel address sanitizer
(see Documentation/kasan.txt).

1/8 of kernel addresses reserved for shadow memory. There was no
big enough hole for this, so virtual addresses for shadow were
stolen from vmalloc area.

At early boot stage the whole shadow region populated with just
one physical page (kasan_zero_page). Later, this page reused
as readonly zero shadow for some memory that KASan currently
don't track (vmalloc).
After mapping the physical memory, pages for shadow memory are
allocated and mapped.

Functions like memset/memmove/memcpy do a lot of memory accesses.
If bad pointer passed to one of these function it is important
to catch this. Compiler's instrumentation cannot do this since
these functions are written in assembly.
KASan replaces memory functions with manually instrumented variants.
Original functions declared as weak symbols so strong definitions
in mm/kasan/kasan.c could replace them. Original functions have aliases
with '__' prefix in name, so we could call non-instrumented variant
if needed.
Some files built without kasan instrumentation (e.g. mm/slub.c).
Original mem* function replaced (via #define) with prefixed variants
to disable memory access checks for such files.

Signed-off-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-12 17:46:36 +01:00
Ard Biesheuvel
207918461e arm64: use ENDPIPROC() to annotate position independent assembler routines
For more control over which functions are called with the MMU off or
with the UEFI 1:1 mapping active, annotate some assembler routines as
position independent. This is done by introducing ENDPIPROC(), which
replaces the ENDPROC() declaration of those routines.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-12 16:19:45 +01:00
Feng Kan
e5c88e3f2f arm64: Change memcpy in kernel to use the copy template file
This converts the memcpy.S to use the copy template file. The copy
template file was based originally on the memcpy.S

Signed-off-by: Feng Kan <fkan@apm.com>
Signed-off-by: Balamurugan Shanmugam <bshanmugam@apm.com>
[catalin.marinas@arm.com: removed tmp3(w) .req statements as they are not used]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-07 11:34:43 +01:00
zhichang.yuan
808dbac6b5 arm64: lib: Implement optimized memcpy routine
This patch, based on Linaro's Cortex Strings library, improves
the performance of the assembly optimized memcpy() function.

Signed-off-by: Zhichang Yuan <zhichang.yuan@linaro.org>
Signed-off-by: Deepak Saxena <dsaxena@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-23 15:06:53 +01:00
Catalin Marinas
4a8992271c arm64: klib: Optimised memory functions
This patch introduces AArch64-specific memory functions (memcpy,
memmove, memchr, memset). These functions are not optimised for any CPU
implementation but can be used as a starting point once hardware is
available.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-03-21 17:39:29 +00:00