Commit 214fad55 authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Catalin Marinas

arm64: relocation testing module

This module tests the module loader's ELF relocation processing
routines. When loaded, it logs output like below.

    Relocation test:
    -------------------------------------------------------
    R_AARCH64_ABS64                 0xffff880000cccccc pass
    R_AARCH64_ABS32                 0x00000000f800cccc pass
    R_AARCH64_ABS16                 0x000000000000f8cc pass
    R_AARCH64_MOVW_SABS_Gn          0xffff880000cccccc pass
    R_AARCH64_MOVW_UABS_Gn          0xffff880000cccccc pass
    R_AARCH64_ADR_PREL_LO21         0xffffff9cf4d1a400 pass
    R_AARCH64_PREL64                0xffffff9cf4d1a400 pass
    R_AARCH64_PREL32                0xffffff9cf4d1a400 pass
    R_AARCH64_PREL16                0xffffff9cf4d1a400 pass
Acked-by: default avatarWill Deacon <will.deacon@arm.com>
Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 46823dd1
......@@ -92,6 +92,10 @@ config DEBUG_EFI
the kernel that are only useful when using a debug build of the
UEFI firmware
config ARM64_RELOC_TEST
depends on m
tristate "Relocation testing module"
source "drivers/hwtracing/coresight/Kconfig"
endmenu
......@@ -50,6 +50,8 @@ arm64-obj-$(CONFIG_RANDOMIZE_BASE) += kaslr.o
arm64-obj-$(CONFIG_HIBERNATION) += hibernate.o hibernate-asm.o
arm64-obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o \
cpu-reset.o
arm64-obj-$(CONFIG_ARM64_RELOC_TEST) += arm64-reloc-test.o
arm64-reloc-test-y := reloc_test_core.o reloc_test_syms.o
obj-y += $(arm64-obj-y) vdso/ probes/
obj-m += $(arm64-obj-m)
......
/*
* Copyright (C) 2017 Linaro, Ltd. <ard.biesheuvel@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/module.h>
int sym64_rel;
#define SYM64_ABS_VAL 0xffff880000cccccc
#define SYM32_ABS_VAL 0xf800cccc
#define SYM16_ABS_VAL 0xf8cc
#define __SET_ABS(name, val) asm(".globl " #name "; .set "#name ", " #val)
#define SET_ABS(name, val) __SET_ABS(name, val)
SET_ABS(sym64_abs, SYM64_ABS_VAL);
SET_ABS(sym32_abs, SYM32_ABS_VAL);
SET_ABS(sym16_abs, SYM16_ABS_VAL);
asmlinkage u64 absolute_data64(void);
asmlinkage u64 absolute_data32(void);
asmlinkage u64 absolute_data16(void);
asmlinkage u64 signed_movw(void);
asmlinkage u64 unsigned_movw(void);
asmlinkage u64 relative_adrp(void);
asmlinkage u64 relative_adr(void);
asmlinkage u64 relative_data64(void);
asmlinkage u64 relative_data32(void);
asmlinkage u64 relative_data16(void);
static struct {
char name[32];
u64 (*f)(void);
u64 expect;
} const funcs[] = {
{ "R_AARCH64_ABS64", absolute_data64, UL(SYM64_ABS_VAL) },
{ "R_AARCH64_ABS32", absolute_data32, UL(SYM32_ABS_VAL) },
{ "R_AARCH64_ABS16", absolute_data16, UL(SYM16_ABS_VAL) },
{ "R_AARCH64_MOVW_SABS_Gn", signed_movw, UL(SYM64_ABS_VAL) },
{ "R_AARCH64_MOVW_UABS_Gn", unsigned_movw, UL(SYM64_ABS_VAL) },
#ifndef CONFIG_ARM64_ERRATUM_843419
{ "R_AARCH64_ADR_PREL_PG_HI21", relative_adrp, (u64)&sym64_rel },
#endif
{ "R_AARCH64_ADR_PREL_LO21", relative_adr, (u64)&sym64_rel },
{ "R_AARCH64_PREL64", relative_data64, (u64)&sym64_rel },
{ "R_AARCH64_PREL32", relative_data32, (u64)&sym64_rel },
{ "R_AARCH64_PREL16", relative_data16, (u64)&sym64_rel },
};
static int reloc_test_init(void)
{
int i;
pr_info("Relocation test:\n");
pr_info("-------------------------------------------------------\n");
for (i = 0; i < ARRAY_SIZE(funcs); i++) {
u64 ret = funcs[i].f();
pr_info("%-31s 0x%016llx %s\n", funcs[i].name, ret,
ret == funcs[i].expect ? "pass" : "fail");
if (ret != funcs[i].expect)
pr_err("Relocation failed, expected 0x%016llx, not 0x%016llx\n",
funcs[i].expect, ret);
}
return 0;
}
static void reloc_test_exit(void)
{
}
module_init(reloc_test_init);
module_exit(reloc_test_exit);
MODULE_LICENSE("GPL v2");
/*
* Copyright (C) 2017 Linaro, Ltd. <ard.biesheuvel@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/linkage.h>
ENTRY(absolute_data64)
ldr x0, 0f
ret
0: .quad sym64_abs
ENDPROC(absolute_data64)
ENTRY(absolute_data32)
ldr w0, 0f
ret
0: .long sym32_abs
ENDPROC(absolute_data32)
ENTRY(absolute_data16)
adr x0, 0f
ldrh w0, [x0]
ret
0: .short sym16_abs, 0
ENDPROC(absolute_data16)
ENTRY(signed_movw)
movz x0, #:abs_g2_s:sym64_abs
movk x0, #:abs_g1_nc:sym64_abs
movk x0, #:abs_g0_nc:sym64_abs
ret
ENDPROC(signed_movw)
ENTRY(unsigned_movw)
movz x0, #:abs_g3:sym64_abs
movk x0, #:abs_g2_nc:sym64_abs
movk x0, #:abs_g1_nc:sym64_abs
movk x0, #:abs_g0_nc:sym64_abs
ret
ENDPROC(unsigned_movw)
#ifndef CONFIG_ARM64_ERRATUM_843419
ENTRY(relative_adrp)
adrp x0, sym64_rel
add x0, x0, #:lo12:sym64_rel
ret
ENDPROC(relative_adrp)
#endif
ENTRY(relative_adr)
adr x0, sym64_rel
ret
ENDPROC(relative_adr)
ENTRY(relative_data64)
adr x1, 0f
ldr x0, [x1]
add x0, x0, x1
ret
0: .quad sym64_rel - .
ENDPROC(relative_data64)
ENTRY(relative_data32)
adr x1, 0f
ldr w0, [x1]
add x0, x0, x1
ret
0: .long sym64_rel - .
ENDPROC(relative_data32)
ENTRY(relative_data16)
adr x1, 0f
ldrsh w0, [x1]
add x0, x0, x1
ret
0: .short sym64_rel - ., 0
ENDPROC(relative_data16)
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