linux-stable/arch/arm/lib/memcpy.S
Fangrui Song 735e8d93dc ARM: 9022/1: Change arch/arm/lib/mem*.S to use WEAK instead of .weak
Commit d6d51a96c7 ("ARM: 9014/2: Replace string mem* functions for
KASan") add .weak directives to memcpy/memmove/memset to avoid collision
with KASAN interceptors.

This does not work with LLVM's integrated assembler (the assembly snippet
`.weak memcpy ... .globl memcpy` produces a STB_GLOBAL memcpy while GNU as
produces a STB_WEAK memcpy). LLVM 12 (since https://reviews.llvm.org/D90108)
will error on such an overridden symbol binding.

Use the appropriate WEAK macro instead.

Link: https://github.com/ClangBuiltLinux/linux/issues/1190
--

Fixes: d6d51a96c7 ("ARM: 9014/2: Replace string mem* functions for KASan")
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-11-12 14:53:19 +00:00

69 lines
1.3 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* linux/arch/arm/lib/memcpy.S
*
* Author: Nicolas Pitre
* Created: Sep 28, 2005
* Copyright: MontaVista Software, Inc.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/unwind.h>
#define LDR1W_SHIFT 0
#define STR1W_SHIFT 0
.macro ldr1w ptr reg abort
W(ldr) \reg, [\ptr], #4
.endm
.macro ldr4w ptr reg1 reg2 reg3 reg4 abort
ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4}
.endm
.macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
.endm
.macro ldr1b ptr reg cond=al abort
ldrb\cond \reg, [\ptr], #1
.endm
.macro str1w ptr reg abort
W(str) \reg, [\ptr], #4
.endm
.macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
.endm
.macro str1b ptr reg cond=al abort
strb\cond \reg, [\ptr], #1
.endm
.macro enter reg1 reg2
stmdb sp!, {r0, \reg1, \reg2}
.endm
.macro usave reg1 reg2
UNWIND( .save {r0, \reg1, \reg2} )
.endm
.macro exit reg1 reg2
ldmfd sp!, {r0, \reg1, \reg2}
.endm
.text
/* Prototype: void *memcpy(void *dest, const void *src, size_t n); */
ENTRY(__memcpy)
ENTRY(mmiocpy)
WEAK(memcpy)
#include "copy_template.S"
ENDPROC(memcpy)
ENDPROC(mmiocpy)
ENDPROC(__memcpy)