Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932195AbaKLB0G (ORCPT ); Tue, 11 Nov 2014 20:26:06 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:58872 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754264AbaKLB0A (ORCPT ); Tue, 11 Nov 2014 20:26:00 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nadav Amit , Paolo Bonzini Subject: [PATCH 3.17 127/319] KVM: x86: Emulator does not decode clflush well Date: Wed, 12 Nov 2014 10:14:25 +0900 Message-Id: <20141112011013.643474103@linuxfoundation.org> X-Mailer: git-send-email 2.1.3 In-Reply-To: <20141112010952.553519040@linuxfoundation.org> References: <20141112010952.553519040@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nadav Amit commit 13e457e0eebf0a0c82c38ceb890d93eb826d62a6 upstream. Currently, all group15 instructions are decoded as clflush (e.g., mfence, xsave). In addition, the clflush instruction requires no prefix (66/f2/f3) would exist. If prefix exists it may encode a different instruction (e.g., clflushopt). Creating a group for clflush, and different group for each prefix. This has been the case forever, but the next patch needs the cflush group in order to fix a bug introduced in 3.17. Fixes: 41061cdb98a0bec464278b4db8e894a3121671f5 Signed-off-by: Nadav Amit Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/emulate.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -3376,6 +3376,12 @@ static int em_bswap(struct x86_emulate_c return X86EMUL_CONTINUE; } +static int em_clflush(struct x86_emulate_ctxt *ctxt) +{ + /* emulating clflush regardless of cpuid */ + return X86EMUL_CONTINUE; +} + static bool valid_cr(int nr) { switch (nr) { @@ -3708,6 +3714,16 @@ static const struct opcode group11[] = { X7(D(Undefined)), }; +static const struct gprefix pfx_0f_ae_7 = { + I(0, em_clflush), N, N, N, +}; + +static const struct group_dual group15 = { { + N, N, N, N, N, N, N, GP(0, &pfx_0f_ae_7), +}, { + N, N, N, N, N, N, N, N, +} }; + static const struct gprefix pfx_0f_6f_0f_7f = { I(Mmx, em_mov), I(Sse | Aligned, em_mov), N, I(Sse | Unaligned, em_mov), }; @@ -3967,7 +3983,7 @@ static const struct opcode twobyte_table F(DstMem | SrcReg | ModRM | BitOp | Lock | PageTable, em_bts), F(DstMem | SrcReg | Src2ImmByte | ModRM, em_shrd), F(DstMem | SrcReg | Src2CL | ModRM, em_shrd), - D(ModRM), F(DstReg | SrcMem | ModRM, em_imul), + GD(0, &group15), F(DstReg | SrcMem | ModRM, em_imul), /* 0xB0 - 0xB7 */ I2bv(DstMem | SrcReg | ModRM | Lock | PageTable, em_cmpxchg), I(DstReg | SrcMemFAddr | ModRM | Src2SS, em_lseg), @@ -4894,8 +4910,6 @@ twobyte_insn: case 0x90 ... 0x9f: /* setcc r/m8 */ ctxt->dst.val = test_cc(ctxt->b, ctxt->eflags); break; - case 0xae: /* clflush */ - break; case 0xb6 ... 0xb7: /* movzx */ ctxt->dst.bytes = ctxt->op_bytes; ctxt->dst.val = (ctxt->src.bytes == 1) ? (u8) ctxt->src.val -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/