From 1d509f2a6ebca1aea3089c769f6375f01a832e9b Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 13 Nov 2020 00:03:23 +0100 Subject: x86/insn: Support big endian cross-compiles The x86 instruction decoder code is shared across the kernel source and the tools. Currently objtool seems to be the only tool from build tools needed which breaks x86 cross-compilation on big endian systems. Make the x86 instruction decoder build host endianness agnostic to support x86 cross-compilation and enable objtool to implement endianness awareness for big endian architectures support. Signed-off-by: Martin Schwidefsky Co-developed-by: Vasily Gorbik Signed-off-by: Vasily Gorbik Acked-by: Peter Zijlstra (Intel) Acked-by: Masami Hiramatsu Signed-off-by: Josh Poimboeuf --- arch/x86/lib/insn.c | 101 ++++++++++++++++++++++++---------------------------- 1 file changed, 47 insertions(+), 54 deletions(-) (limited to 'arch/x86/lib') diff --git a/arch/x86/lib/insn.c b/arch/x86/lib/insn.c index 404279563891..520b31fc1f1a 100644 --- a/arch/x86/lib/insn.c +++ b/arch/x86/lib/insn.c @@ -5,6 +5,7 @@ * Copyright (C) IBM Corporation, 2002, 2004, 2009 */ +#include #ifdef __KERNEL__ #include #else @@ -15,15 +16,28 @@ #include +#define leXX_to_cpu(t, r) \ +({ \ + __typeof__(t) v; \ + switch (sizeof(t)) { \ + case 4: v = le32_to_cpu(r); break; \ + case 2: v = le16_to_cpu(r); break; \ + case 1: v = r; break; \ + default: \ + BUILD_BUG(); break; \ + } \ + v; \ +}) + /* Verify next sizeof(t) bytes can be on the same instruction */ #define validate_next(t, insn, n) \ ((insn)->next_byte + sizeof(t) + n <= (insn)->end_kaddr) #define __get_next(t, insn) \ - ({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); r; }) + ({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); leXX_to_cpu(t, r); }) #define __peek_nbyte_next(t, insn, n) \ - ({ t r = *(t*)((insn)->next_byte + n); r; }) + ({ t r = *(t*)((insn)->next_byte + n); leXX_to_cpu(t, r); }) #define get_next(t, insn) \ ({ if (unlikely(!validate_next(t, insn, 0))) goto err_out; __get_next(t, insn); }) @@ -157,8 +171,7 @@ found: b = peek_next(insn_byte_t, insn); attr = inat_get_opcode_attribute(b); if (inat_is_rex_prefix(attr)) { - insn->rex_prefix.value = b; - insn->rex_prefix.nbytes = 1; + insn_field_set(&insn->rex_prefix, b, 1); insn->next_byte++; if (X86_REX_W(b)) /* REX.W overrides opnd_size */ @@ -295,8 +308,7 @@ void insn_get_modrm(struct insn *insn) if (inat_has_modrm(insn->attr)) { mod = get_next(insn_byte_t, insn); - modrm->value = mod; - modrm->nbytes = 1; + insn_field_set(modrm, mod, 1); if (inat_is_group(insn->attr)) { pfx_id = insn_last_prefix_id(insn); insn->attr = inat_get_group_attribute(mod, pfx_id, @@ -334,7 +346,7 @@ int insn_rip_relative(struct insn *insn) * For rip-relative instructions, the mod field (top 2 bits) * is zero and the r/m field (bottom 3 bits) is 0x5. */ - return (modrm->nbytes && (modrm->value & 0xc7) == 0x5); + return (modrm->nbytes && (modrm->bytes[0] & 0xc7) == 0x5); } /** @@ -353,11 +365,11 @@ void insn_get_sib(struct insn *insn) if (!insn->modrm.got) insn_get_modrm(insn); if (insn->modrm.nbytes) { - modrm = (insn_byte_t)insn->modrm.value; + modrm = insn->modrm.bytes[0]; if (insn->addr_bytes != 2 && X86_MODRM_MOD(modrm) != 3 && X86_MODRM_RM(modrm) == 4) { - insn->sib.value = get_next(insn_byte_t, insn); - insn->sib.nbytes = 1; + insn_field_set(&insn->sib, + get_next(insn_byte_t, insn), 1); } } insn->sib.got = 1; @@ -407,19 +419,18 @@ void insn_get_displacement(struct insn *insn) if (mod == 3) goto out; if (mod == 1) { - insn->displacement.value = get_next(signed char, insn); - insn->displacement.nbytes = 1; + insn_field_set(&insn->displacement, + get_next(signed char, insn), 1); } else if (insn->addr_bytes == 2) { if ((mod == 0 && rm == 6) || mod == 2) { - insn->displacement.value = - get_next(short, insn); - insn->displacement.nbytes = 2; + insn_field_set(&insn->displacement, + get_next(short, insn), 2); } } else { if ((mod == 0 && rm == 5) || mod == 2 || (mod == 0 && base == 5)) { - insn->displacement.value = get_next(int, insn); - insn->displacement.nbytes = 4; + insn_field_set(&insn->displacement, + get_next(int, insn), 4); } } } @@ -435,18 +446,14 @@ static int __get_moffset(struct insn *insn) { switch (insn->addr_bytes) { case 2: - insn->moffset1.value = get_next(short, insn); - insn->moffset1.nbytes = 2; + insn_field_set(&insn->moffset1, get_next(short, insn), 2); break; case 4: - insn->moffset1.value = get_next(int, insn); - insn->moffset1.nbytes = 4; + insn_field_set(&insn->moffset1, get_next(int, insn), 4); break; case 8: - insn->moffset1.value = get_next(int, insn); - insn->moffset1.nbytes = 4; - insn->moffset2.value = get_next(int, insn); - insn->moffset2.nbytes = 4; + insn_field_set(&insn->moffset1, get_next(int, insn), 4); + insn_field_set(&insn->moffset2, get_next(int, insn), 4); break; default: /* opnd_bytes must be modified manually */ goto err_out; @@ -464,13 +471,11 @@ static int __get_immv32(struct insn *insn) { switch (insn->opnd_bytes) { case 2: - insn->immediate.value = get_next(short, insn); - insn->immediate.nbytes = 2; + insn_field_set(&insn->immediate, get_next(short, insn), 2); break; case 4: case 8: - insn->immediate.value = get_next(int, insn); - insn->immediate.nbytes = 4; + insn_field_set(&insn->immediate, get_next(int, insn), 4); break; default: /* opnd_bytes must be modified manually */ goto err_out; @@ -487,18 +492,15 @@ static int __get_immv(struct insn *insn) { switch (insn->opnd_bytes) { case 2: - insn->immediate1.value = get_next(short, insn); - insn->immediate1.nbytes = 2; + insn_field_set(&insn->immediate1, get_next(short, insn), 2); break; case 4: - insn->immediate1.value = get_next(int, insn); + insn_field_set(&insn->immediate1, get_next(int, insn), 4); insn->immediate1.nbytes = 4; break; case 8: - insn->immediate1.value = get_next(int, insn); - insn->immediate1.nbytes = 4; - insn->immediate2.value = get_next(int, insn); - insn->immediate2.nbytes = 4; + insn_field_set(&insn->immediate1, get_next(int, insn), 4); + insn_field_set(&insn->immediate2, get_next(int, insn), 4); break; default: /* opnd_bytes must be modified manually */ goto err_out; @@ -515,12 +517,10 @@ static int __get_immptr(struct insn *insn) { switch (insn->opnd_bytes) { case 2: - insn->immediate1.value = get_next(short, insn); - insn->immediate1.nbytes = 2; + insn_field_set(&insn->immediate1, get_next(short, insn), 2); break; case 4: - insn->immediate1.value = get_next(int, insn); - insn->immediate1.nbytes = 4; + insn_field_set(&insn->immediate1, get_next(int, insn), 4); break; case 8: /* ptr16:64 is not exist (no segment) */ @@ -528,8 +528,7 @@ static int __get_immptr(struct insn *insn) default: /* opnd_bytes must be modified manually */ goto err_out; } - insn->immediate2.value = get_next(unsigned short, insn); - insn->immediate2.nbytes = 2; + insn_field_set(&insn->immediate2, get_next(unsigned short, insn), 2); insn->immediate1.got = insn->immediate2.got = 1; return 1; @@ -565,22 +564,17 @@ void insn_get_immediate(struct insn *insn) switch (inat_immediate_size(insn->attr)) { case INAT_IMM_BYTE: - insn->immediate.value = get_next(signed char, insn); - insn->immediate.nbytes = 1; + insn_field_set(&insn->immediate, get_next(signed char, insn), 1); break; case INAT_IMM_WORD: - insn->immediate.value = get_next(short, insn); - insn->immediate.nbytes = 2; + insn_field_set(&insn->immediate, get_next(short, insn), 2); break; case INAT_IMM_DWORD: - insn->immediate.value = get_next(int, insn); - insn->immediate.nbytes = 4; + insn_field_set(&insn->immediate, get_next(int, insn), 4); break; case INAT_IMM_QWORD: - insn->immediate1.value = get_next(int, insn); - insn->immediate1.nbytes = 4; - insn->immediate2.value = get_next(int, insn); - insn->immediate2.nbytes = 4; + insn_field_set(&insn->immediate1, get_next(int, insn), 4); + insn_field_set(&insn->immediate2, get_next(int, insn), 4); break; case INAT_IMM_PTR: if (!__get_immptr(insn)) @@ -599,8 +593,7 @@ void insn_get_immediate(struct insn *insn) goto err_out; } if (inat_has_second_immediate(insn->attr)) { - insn->immediate2.value = get_next(signed char, insn); - insn->immediate2.nbytes = 1; + insn_field_set(&insn->immediate2, get_next(signed char, insn), 1); } done: insn->immediate.got = 1; -- cgit v1.2.3-70-g09d2