From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4BAC2C433FE for ; Wed, 25 May 2022 22:26:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345438AbiEYW01 (ORCPT ); Wed, 25 May 2022 18:26:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55506 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345379AbiEYW0R (ORCPT ); Wed, 25 May 2022 18:26:17 -0400 Received: from mail-pf1-x449.google.com (mail-pf1-x449.google.com [IPv6:2607:f8b0:4864:20::449]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C118276 for ; Wed, 25 May 2022 15:26:14 -0700 (PDT) Received: by mail-pf1-x449.google.com with SMTP id g69-20020a625248000000b00519150d186bso70532pfb.18 for ; Wed, 25 May 2022 15:26:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=1K6OM5CVosmRq7VrXJUvnPyF0+jKI5Wt9fyUJ3K2ibY=; b=L3C+sxFViTeVKuyVx5ivxoNs7Q6DYSLINTgXeRAUuwL1UVebb8TNStoOpMZyfvPmh7 VU+hFtXQ2sdfPs465VxYnDTutAK2XRTNQbBz9Ht2PHH4sRve6QgaSf01OMCXm63bwqGN TKTmrdaY1EGLCOpSa1LH4g3mL/V1MYdFetwPFYdxNhlDI/DlnnvqFaqX7Rlc/ppN4zPf DuaG4mikEbaBkcOsHBWoOcI666PRRP/tDC3SdopDwzkvXYU/pb8XHb5sg7iqFnV+HFHI 3TFgrrEBIOIymBspGi1iMC95/Q0EQ7VwvHnH9BoFgOlQu0+mPtt4RWu/eB7M/uC2JEsb 7IYg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=1K6OM5CVosmRq7VrXJUvnPyF0+jKI5Wt9fyUJ3K2ibY=; b=e3LyocV4rXS0jpIZ6MtcqvSSgW4LtSFkcjz+vWSmBtc56dFZybQFqgxoyjrPop7xUK pveCup4e5615jF9X6ZCLOAdwZzhVJyKcSwH7tqUY6qldJ2B+QYLX/56tO7Ylf1YGcmoH 5QeBXrRJK8kJhJpe6x3F9LqhYR2l/Fd2jWh1T33I1/aDWc3zxZrXAp0koqKW+UVjcvUT EPHegRZBy7vZAiJMAVD6sIGoo+CKKp8Fx24yQCNun2m19LD3ajQAtk8RLBz8ztEGibIV tJhzbnE3f1nLUOgQzOcvGFm5ApaPKFROIpytlo4TMdKvcWoyKBFowsCqfMpMjhV0xi05 7I8g== X-Gm-Message-State: AOAM532/T4BByAZHlG1vpRVAiqbtEgi+ftiJUkQiExaCLfiQt6N/5v2y tmrF4BG5q+YXadBkbwGbGyFHtGEa4DA= X-Google-Smtp-Source: ABdhPJy88zKrcNaUS/fJ+z8CMMhWxSLqAWS1xOCdoT7FwuQTGaaLJiJLN6NuKX+u7dqcA6a7HXAciPgJN2E= X-Received: from seanjc.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3e5]) (user=seanjc job=sendgmr) by 2002:a17:90b:1192:b0:1e0:63f3:c463 with SMTP id gk18-20020a17090b119200b001e063f3c463mr30564pjb.1.1653517573248; Wed, 25 May 2022 15:26:13 -0700 (PDT) Reply-To: Sean Christopherson Date: Wed, 25 May 2022 22:26:03 +0000 In-Reply-To: <20220525222604.2810054-1-seanjc@google.com> Message-Id: <20220525222604.2810054-4-seanjc@google.com> Mime-Version: 1.0 References: <20220525222604.2810054-1-seanjc@google.com> X-Mailer: git-send-email 2.36.1.124.g0e6072fb45-goog Subject: [PATCH 3/4] KVM: x86: Omit VCPU_REGS_RIP from emulator's _regs array From: Sean Christopherson To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Robert Dinse , Kees Cook Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Omit RIP from the emulator's _regs array, which is used only for GPRs, i.e. registers that can be referenced via ModRM and/or SIB bytes. The emulator uses the dedicated _eip field for RIP, and manually reads from _eip to handle RIP-relative addressing. Replace all open coded instances of '16' with the new NR_EMULATOR_GPRS. See also the comments above the read_gpr() and write_gpr() declarations, and obviously the handling in writeback_registers(). No functional change intended. Signed-off-by: Sean Christopherson --- arch/x86/kvm/emulate.c | 12 ++++++------ arch/x86/kvm/kvm_emulate.h | 10 +++++++++- 2 files changed, 15 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index c58366ae4da2..dd1bf116a9ed 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -247,8 +247,8 @@ enum x86_transfer_type { static ulong reg_read(struct x86_emulate_ctxt *ctxt, unsigned nr) { - if (WARN_ON_ONCE(nr >= 16)) - nr &= 16 - 1; + if (WARN_ON_ONCE(nr >= NR_EMULATOR_GPRS)) + nr &= NR_EMULATOR_GPRS - 1; if (!(ctxt->regs_valid & (1 << nr))) { ctxt->regs_valid |= 1 << nr; @@ -259,8 +259,8 @@ static ulong reg_read(struct x86_emulate_ctxt *ctxt, unsigned nr) static ulong *reg_write(struct x86_emulate_ctxt *ctxt, unsigned nr) { - if (WARN_ON_ONCE(nr >= 16)) - nr &= 16 - 1; + if (WARN_ON_ONCE(nr >= NR_EMULATOR_GPRS)) + nr &= NR_EMULATOR_GPRS - 1; ctxt->regs_valid |= 1 << nr; ctxt->regs_dirty |= 1 << nr; @@ -278,7 +278,7 @@ static void writeback_registers(struct x86_emulate_ctxt *ctxt) unsigned long dirty = ctxt->regs_dirty; unsigned reg; - for_each_set_bit(reg, &dirty, 16) + for_each_set_bit(reg, &dirty, NR_EMULATOR_GPRS) ctxt->ops->write_gpr(ctxt, reg, ctxt->_regs[reg]); } @@ -2495,7 +2495,7 @@ static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt, u16 selector; int i, r; - for (i = 0; i < 16; i++) + for (i = 0; i < NR_EMULATOR_GPRS; i++) *reg_write(ctxt, i) = GET_SMSTATE(u64, smstate, 0x7ff8 - i * 8); ctxt->_eip = GET_SMSTATE(u64, smstate, 0x7f78); diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h index 8dff25d267b7..bdd4e9865ca9 100644 --- a/arch/x86/kvm/kvm_emulate.h +++ b/arch/x86/kvm/kvm_emulate.h @@ -301,6 +301,14 @@ struct fastop; typedef void (*fastop_t)(struct fastop *); +/* + * The emulator's _regs array tracks only the GPRs, i.e. excludes RIP. RIP is + * tracked/accessed via _eip, and except for RIP relative addressing, which + * also uses _eip, RIP cannot be a register operand nor can it be an operand in + * a ModRM or SIB byte. + */ +#define NR_EMULATOR_GPRS (VCPU_REGS_R15 + 1) + struct x86_emulate_ctxt { void *vcpu; const struct x86_emulate_ops *ops; @@ -363,7 +371,7 @@ struct x86_emulate_ctxt { struct operand src2; struct operand dst; struct operand memop; - unsigned long _regs[NR_VCPU_REGS]; + unsigned long _regs[NR_EMULATOR_GPRS]; struct operand *memopp; struct fetch_cache fetch; struct read_cache io_read; -- 2.36.1.124.g0e6072fb45-goog