From patchwork Mon Jul 23 19:32:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 10540807 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 56E781822 for ; Mon, 23 Jul 2018 19:33:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 45DA72832D for ; Mon, 23 Jul 2018 19:33:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 39B27283CF; Mon, 23 Jul 2018 19:33:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C7B572832D for ; Mon, 23 Jul 2018 19:33:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388071AbeGWUgJ (ORCPT ); Mon, 23 Jul 2018 16:36:09 -0400 Received: from mga02.intel.com ([134.134.136.20]:3729 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388058AbeGWUgI (ORCPT ); Mon, 23 Jul 2018 16:36:08 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 23 Jul 2018 12:33:27 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,394,1526367600"; d="scan'208";a="247679506" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.132]) by fmsmga005.fm.intel.com with ESMTP; 23 Jul 2018 12:32:53 -0700 From: Sean Christopherson To: kvm@vger.kernel.org, pbonzini@redhat.com, rkrcmar@redhat.com Cc: sean.j.christopherson@intel.com Subject: [PATCH 02/11] KVM: vmx: refactor segmentation code in vmx_save_host_state() Date: Mon, 23 Jul 2018 12:32:41 -0700 Message-Id: <20180723193250.13555-3-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180723193250.13555-1-sean.j.christopherson@intel.com> References: <20180723193250.13555-1-sean.j.christopherson@intel.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Use local variables in vmx_save_host_state() to temporarily track the selector and base values for FS and GS, and reorganize the code so that the 64-bit vs 32-bit portions are contained within a single #ifdef. This refactoring paves the way for future patches to modify the updating of VMCS state with minimal changes to the code, and (hopefully) simplifies resolving a likely conflict with another in-flight patch[1] by being the whipping boy for future patches. [1] https://www.spinics.net/lists/kvm/msg171647.html Signed-off-by: Sean Christopherson Reviewed-by: Peter Shier Tested-by: Peter Shier --- arch/x86/kvm/vmx.c | 47 +++++++++++++++++++++++++--------------------- 1 file changed, 26 insertions(+), 21 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 553bf26af831..d17c94351ac7 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2572,6 +2572,8 @@ static void vmx_save_host_state(struct kvm_vcpu *vcpu) #ifdef CONFIG_X86_64 int cpu = raw_smp_processor_id(); #endif + unsigned long fs_base, gs_base; + u16 fs_sel, gs_sel; int i; if (vmx->host_state.loaded) @@ -2586,41 +2588,44 @@ static void vmx_save_host_state(struct kvm_vcpu *vcpu) vmx->host_state.gs_ldt_reload_needed = vmx->host_state.ldt_sel; #ifdef CONFIG_X86_64 + savesegment(ds, vmx->host_state.ds_sel); + savesegment(es, vmx->host_state.es_sel); + save_fsgs_for_kvm(); - vmx->host_state.fs_sel = current->thread.fsindex; - vmx->host_state.gs_sel = current->thread.gsindex; + fs_sel = current->thread.fsindex; + gs_sel = current->thread.gsindex; + fs_base = current->thread.fsbase; + gs_base = cpu_kernelmode_gs_base(cpu); + + vmx->msr_host_kernel_gs_base = current->thread.gsbase; + if (is_long_mode(&vmx->vcpu)) + wrmsrl(MSR_KERNEL_GS_BASE, vmx->msr_guest_kernel_gs_base); #else - savesegment(fs, vmx->host_state.fs_sel); - savesegment(gs, vmx->host_state.gs_sel); + savesegment(fs, fs_sel); + savesegment(gs, gs_sel); + fs_base = segment_base(fs_sel); + gs_base = segment_base(gs_sel); #endif - if (!(vmx->host_state.fs_sel & 7)) { - vmcs_write16(HOST_FS_SELECTOR, vmx->host_state.fs_sel); + + vmx->host_state.fs_sel = fs_sel; + if (!(fs_sel & 7)) { + vmcs_write16(HOST_FS_SELECTOR, fs_sel); vmx->host_state.fs_reload_needed = 0; } else { vmcs_write16(HOST_FS_SELECTOR, 0); vmx->host_state.fs_reload_needed = 1; } - if (!(vmx->host_state.gs_sel & 7)) - vmcs_write16(HOST_GS_SELECTOR, vmx->host_state.gs_sel); + vmx->host_state.gs_sel = gs_sel; + if (!(gs_sel & 7)) + vmcs_write16(HOST_GS_SELECTOR, gs_sel); else { vmcs_write16(HOST_GS_SELECTOR, 0); vmx->host_state.gs_ldt_reload_needed = 1; } -#ifdef CONFIG_X86_64 - savesegment(ds, vmx->host_state.ds_sel); - savesegment(es, vmx->host_state.es_sel); + vmcs_writel(HOST_FS_BASE, fs_base); + vmcs_writel(HOST_GS_BASE, gs_base); - vmcs_writel(HOST_FS_BASE, current->thread.fsbase); - vmcs_writel(HOST_GS_BASE, cpu_kernelmode_gs_base(cpu)); - - vmx->msr_host_kernel_gs_base = current->thread.gsbase; - if (is_long_mode(&vmx->vcpu)) - wrmsrl(MSR_KERNEL_GS_BASE, vmx->msr_guest_kernel_gs_base); -#else - vmcs_writel(HOST_FS_BASE, segment_base(vmx->host_state.fs_sel)); - vmcs_writel(HOST_GS_BASE, segment_base(vmx->host_state.gs_sel)); -#endif if (boot_cpu_has(X86_FEATURE_MPX)) rdmsrl(MSR_IA32_BNDCFGS, vmx->msr_host_bndcfgs); for (i = 0; i < vmx->save_nmsrs; ++i)