103 lines
2.5 KiB
ArmAsm
103 lines
2.5 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0 */
|
|
|
|
#include <linux/stringify.h>
|
|
#include <linux/linkage.h>
|
|
#include <asm/dwarf2.h>
|
|
#include <asm/cpufeatures.h>
|
|
#include <asm/alternative.h>
|
|
#include <asm/export.h>
|
|
#include <asm/nospec-branch.h>
|
|
#include <asm/unwind_hints.h>
|
|
#include <asm/frame.h>
|
|
|
|
.section .text.__x86.indirect_thunk
|
|
|
|
.macro RETPOLINE reg
|
|
ANNOTATE_INTRA_FUNCTION_CALL
|
|
call .Ldo_rop_\@
|
|
.Lspec_trap_\@:
|
|
UNWIND_HINT_EMPTY
|
|
pause
|
|
lfence
|
|
jmp .Lspec_trap_\@
|
|
.Ldo_rop_\@:
|
|
mov %\reg, (%_ASM_SP)
|
|
UNWIND_HINT_FUNC
|
|
ret
|
|
.endm
|
|
|
|
.macro THUNK reg
|
|
|
|
.align 32
|
|
|
|
SYM_FUNC_START(__x86_indirect_thunk_\reg)
|
|
|
|
ALTERNATIVE_2 __stringify(ANNOTATE_RETPOLINE_SAFE; jmp *%\reg), \
|
|
__stringify(RETPOLINE \reg), X86_FEATURE_RETPOLINE, \
|
|
__stringify(lfence; ANNOTATE_RETPOLINE_SAFE; jmp *%\reg), X86_FEATURE_RETPOLINE_AMD
|
|
|
|
SYM_FUNC_END(__x86_indirect_thunk_\reg)
|
|
|
|
.endm
|
|
|
|
/*
|
|
* This generates .altinstr_replacement symbols for use by objtool. They,
|
|
* however, must not actually live in .altinstr_replacement since that will be
|
|
* discarded after init, but module alternatives will also reference these
|
|
* symbols.
|
|
*
|
|
* Their names matches the "__x86_indirect_" prefix to mark them as retpolines.
|
|
*/
|
|
.macro ALT_THUNK reg
|
|
|
|
.align 1
|
|
|
|
SYM_FUNC_START_NOALIGN(__x86_indirect_alt_call_\reg)
|
|
ANNOTATE_RETPOLINE_SAFE
|
|
1: call *%\reg
|
|
2: .skip 5-(2b-1b), 0x90
|
|
SYM_FUNC_END(__x86_indirect_alt_call_\reg)
|
|
|
|
SYM_FUNC_START_NOALIGN(__x86_indirect_alt_jmp_\reg)
|
|
ANNOTATE_RETPOLINE_SAFE
|
|
1: jmp *%\reg
|
|
2: .skip 5-(2b-1b), 0x90
|
|
SYM_FUNC_END(__x86_indirect_alt_jmp_\reg)
|
|
|
|
.endm
|
|
|
|
/*
|
|
* Despite being an assembler file we can't just use .irp here
|
|
* because __KSYM_DEPS__ only uses the C preprocessor and would
|
|
* only see one instance of "__x86_indirect_thunk_\reg" rather
|
|
* than one per register with the correct names. So we do it
|
|
* the simple and nasty way...
|
|
*
|
|
* Worse, you can only have a single EXPORT_SYMBOL per line,
|
|
* and CPP can't insert newlines, so we have to repeat everything
|
|
* at least twice.
|
|
*/
|
|
|
|
#define __EXPORT_THUNK(sym) _ASM_NOKPROBE(sym); EXPORT_SYMBOL(sym)
|
|
#define EXPORT_THUNK(reg) __EXPORT_THUNK(__x86_indirect_thunk_ ## reg)
|
|
|
|
#undef GEN
|
|
#define GEN(reg) THUNK reg
|
|
#include <asm/GEN-for-each-reg.h>
|
|
|
|
#undef GEN
|
|
#define GEN(reg) EXPORT_THUNK(reg)
|
|
#include <asm/GEN-for-each-reg.h>
|
|
|
|
#undef GEN
|
|
#define GEN(reg) ALT_THUNK reg
|
|
#include <asm/GEN-for-each-reg.h>
|
|
|
|
#undef GEN
|
|
#define GEN(reg) __EXPORT_THUNK(__x86_indirect_alt_call_ ## reg)
|
|
#include <asm/GEN-for-each-reg.h>
|
|
|
|
#undef GEN
|
|
#define GEN(reg) __EXPORT_THUNK(__x86_indirect_alt_jmp_ ## reg)
|
|
#include <asm/GEN-for-each-reg.h>
|