From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 31829 invoked by alias); 23 May 2009 00:52:45 -0000 Received: (qmail 31781 invoked by uid 22791); 23 May 2009 00:52:42 -0000 X-SWARE-Spam-Status: No, hits=-0.6 required=5.0 tests=AWL,BAYES_50,SPF_HELO_PASS,SPF_PASS X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (66.187.233.31) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sat, 23 May 2009 00:52:36 +0000 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id n4N0PXV6002670 for ; Fri, 22 May 2009 20:25:33 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n4N0PXq7011418 for ; Fri, 22 May 2009 20:25:33 -0400 Received: from localhost.localdomain (dhcp-100-3-156.bos.redhat.com [10.16.3.156]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n4N0PX9N000641; Fri, 22 May 2009 20:25:33 -0400 From: Masami Hiramatsu Subject: [PATCH -tip v7 4/6] kprobes: cleanup fix_riprel() using insn decoder on x86 To: Ingo Molnar , Steven Rostedt , lkml Cc: systemtap, kvm, DLE, Masami Hiramatsu , Ananth N Mavinakayanahalli , Jim Keniston , Ingo Molnar Date: Sat, 23 May 2009 00:52:00 -0000 Message-ID: <20090523002845.8948.94212.stgit@localhost.localdomain> In-Reply-To: <20090523002830.8948.51194.stgit@localhost.localdomain> References: <20090523002830.8948.51194.stgit@localhost.localdomain> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2009-q2/txt/msg00690.txt.bz2 Cleanup fix_riprel() in arch/x86/kernel/kprobes.c by using x86 instruction decoder. Signed-off-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: Jim Keniston Cc: Ingo Molnar --- arch/x86/kernel/kprobes.c | 128 ++++++++------------------------------------- 1 files changed, 23 insertions(+), 105 deletions(-) diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c index 41d524f..ebac470 100644 --- a/arch/x86/kernel/kprobes.c +++ b/arch/x86/kernel/kprobes.c @@ -108,50 +108,6 @@ static const u32 twobyte_is_boostable[256 / 32] = { /* ----------------------------------------------- */ /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ }; -static const u32 onebyte_has_modrm[256 / 32] = { - /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ - /* ----------------------------------------------- */ - W(0x00, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0) | /* 00 */ - W(0x10, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0) , /* 10 */ - W(0x20, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0) | /* 20 */ - W(0x30, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0) , /* 30 */ - W(0x40, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0) | /* 40 */ - W(0x50, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0) , /* 50 */ - W(0x60, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0) | /* 60 */ - W(0x70, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0) , /* 70 */ - W(0x80, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1) | /* 80 */ - W(0x90, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0) , /* 90 */ - W(0xa0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0) | /* a0 */ - W(0xb0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0) , /* b0 */ - W(0xc0, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0) | /* c0 */ - W(0xd0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1) , /* d0 */ - W(0xe0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0) | /* e0 */ - W(0xf0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1) /* f0 */ - /* ----------------------------------------------- */ - /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ -}; -static const u32 twobyte_has_modrm[256 / 32] = { - /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ - /* ----------------------------------------------- */ - W(0x00, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1) | /* 0f */ - W(0x10, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0) , /* 1f */ - W(0x20, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1) | /* 2f */ - W(0x30, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0) , /* 3f */ - W(0x40, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1) | /* 4f */ - W(0x50, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1) , /* 5f */ - W(0x60, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1) | /* 6f */ - W(0x70, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1) , /* 7f */ - W(0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0) | /* 8f */ - W(0x90, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1) , /* 9f */ - W(0xa0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1) | /* af */ - W(0xb0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1) , /* bf */ - W(0xc0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0) | /* cf */ - W(0xd0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1) , /* df */ - W(0xe0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1) | /* ef */ - W(0xf0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0) /* ff */ - /* ----------------------------------------------- */ - /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ -}; #undef W struct kretprobe_blackpoint kretprobe_blacklist[] = { @@ -344,68 +300,30 @@ static int __kprobes is_IF_modifier(kprobe_opcode_t *insn) static void __kprobes fix_riprel(struct kprobe *p) { #ifdef CONFIG_X86_64 - u8 *insn = p->ainsn.insn; - s64 disp; - int need_modrm; - - /* Skip legacy instruction prefixes. */ - while (1) { - switch (*insn) { - case 0x66: - case 0x67: - case 0x2e: - case 0x3e: - case 0x26: - case 0x64: - case 0x65: - case 0x36: - case 0xf0: - case 0xf3: - case 0xf2: - ++insn; - continue; - } - break; - } + struct insn insn; + kernel_insn_init(&insn, p->ainsn.insn); - /* Skip REX instruction prefix. */ - if (is_REX_prefix(insn)) - ++insn; - - if (*insn == 0x0f) { - /* Two-byte opcode. */ - ++insn; - need_modrm = test_bit(*insn, - (unsigned long *)twobyte_has_modrm); - } else - /* One-byte opcode. */ - need_modrm = test_bit(*insn, - (unsigned long *)onebyte_has_modrm); - - if (need_modrm) { - u8 modrm = *++insn; - if ((modrm & 0xc7) == 0x05) { - /* %rip+disp32 addressing mode */ - /* Displacement follows ModRM byte. */ - ++insn; - /* - * The copied instruction uses the %rip-relative - * addressing mode. Adjust the displacement for the - * difference between the original location of this - * instruction and the location of the copy that will - * actually be run. The tricky bit here is making sure - * that the sign extension happens correctly in this - * calculation, since we need a signed 32-bit result to - * be sign-extended to 64 bits when it's added to the - * %rip value and yield the same 64-bit result that the - * sign-extension of the original signed 32-bit - * displacement would have given. - */ - disp = (u8 *) p->addr + *((s32 *) insn) - - (u8 *) p->ainsn.insn; - BUG_ON((s64) (s32) disp != disp); /* Sanity check. */ - *(s32 *)insn = (s32) disp; - } + if (insn_rip_relative(&insn)) { + s64 newdisp; + u8 *disp; + insn_get_displacement(&insn); + /* + * The copied instruction uses the %rip-relative addressing + * mode. Adjust the displacement for the difference between + * the original location of this instruction and the location + * of the copy that will actually be run. The tricky bit here + * is making sure that the sign extension happens correctly in + * this calculation, since we need a signed 32-bit result to + * be sign-extended to 64 bits when it's added to the %rip + * value and yield the same 64-bit result that the sign- + * extension of the original signed 32-bit displacement would + * have given. + */ + newdisp = (u8 *) p->addr + (s64) insn.displacement.value - + (u8 *) p->ainsn.insn; + BUG_ON((s64) (s32) newdisp != newdisp); /* Sanity check. */ + disp = (u8 *) p->ainsn.insn + INSN_DISPLACEMENT_OFFS(&insn); + *(s32 *) disp = (s32) newdisp; } #endif } -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America) Inc. Software Solutions Division e-mail: mhiramat@redhat.com