From patchwork Sun May 23 19:32:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Chang S. Bae" X-Patchwork-Id: 12275043 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C7564C47080 for ; Sun, 23 May 2021 19:38:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9503E611ED for ; Sun, 23 May 2021 19:38:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231968AbhEWTj4 (ORCPT ); Sun, 23 May 2021 15:39:56 -0400 Received: from mga11.intel.com ([192.55.52.93]:31996 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231910AbhEWTjz (ORCPT ); Sun, 23 May 2021 15:39:55 -0400 IronPort-SDR: 4Fw3zUvdBrEhKbjxZSur2OLjXrSQ/ilmwLuxraFbQvieNzxzwkRukDRAPRKfNkMk+48yGza3UP beZx2z+ix1bQ== X-IronPort-AV: E=McAfee;i="6200,9189,9993"; a="198740673" X-IronPort-AV: E=Sophos;i="5.82,319,1613462400"; d="scan'208";a="198740673" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 May 2021 12:38:28 -0700 IronPort-SDR: jJ4a1+VHkwPr2jHCF69gssAtV4aoCUhdOrpzyYldyfuUHyhmxIh5nnVzKtEKF/NkfT4ZT3VOZ8 Nwrl6XQWXldQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,319,1613462400"; d="scan'208";a="407467062" Received: from chang-linux-3.sc.intel.com ([172.25.66.175]) by fmsmga007.fm.intel.com with ESMTP; 23 May 2021 12:38:27 -0700 From: "Chang S. Bae" To: bp@suse.de, luto@kernel.org, tglx@linutronix.de, mingo@kernel.org, x86@kernel.org Cc: len.brown@intel.com, dave.hansen@intel.com, jing2.liu@intel.com, ravi.v.shankar@intel.com, linux-kernel@vger.kernel.org, chang.seok.bae@intel.com, kvm@vger.kernel.org Subject: [PATCH v5 01/28] x86/fpu/xstate: Modify the initialization helper to handle both static and dynamic buffers Date: Sun, 23 May 2021 12:32:32 -0700 Message-Id: <20210523193259.26200-2-chang.seok.bae@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210523193259.26200-1-chang.seok.bae@intel.com> References: <20210523193259.26200-1-chang.seok.bae@intel.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Have the function initializing the xstate buffer take a struct fpu * pointer in preparation for dynamic state buffer support. init_fpstate is a special case, which is indicated by a null pointer parameter to fpstate_init(). Also, fpstate_init_xstate() now accepts the state component bitmap to configure XCOMP_BV for the compacted format. No functional change. Signed-off-by: Chang S. Bae Reviewed-by: Len Brown Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org --- Changes from v4: * Added a proper function description. (Borislav Petkov) * Added the likely() statement as a null pointer is a special case. Changes from v3: * Updated the changelog. (Borislav Petkov) * Updated the function comment to use kernel-doc style. (Borislav Petkov) Changes from v2: * Updated the changelog with task->fpu removed. (Borislav Petkov) --- arch/x86/include/asm/fpu/internal.h | 6 +++--- arch/x86/kernel/fpu/core.c | 23 ++++++++++++++++++++--- arch/x86/kernel/fpu/init.c | 2 +- arch/x86/kernel/fpu/regset.c | 2 +- arch/x86/kernel/fpu/xstate.c | 3 +-- arch/x86/kvm/x86.c | 2 +- 6 files changed, 27 insertions(+), 11 deletions(-) diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index 8d33ad80704f..d81d8c407dc0 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -80,20 +80,20 @@ static __always_inline __pure bool use_fxsr(void) extern union fpregs_state init_fpstate; -extern void fpstate_init(union fpregs_state *state); +extern void fpstate_init(struct fpu *fpu); #ifdef CONFIG_MATH_EMULATION extern void fpstate_init_soft(struct swregs_state *soft); #else static inline void fpstate_init_soft(struct swregs_state *soft) {} #endif -static inline void fpstate_init_xstate(struct xregs_state *xsave) +static inline void fpstate_init_xstate(struct xregs_state *xsave, u64 xcomp_mask) { /* * XRSTORS requires these bits set in xcomp_bv, or it will * trigger #GP: */ - xsave->header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT | xfeatures_mask_all; + xsave->header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT | xcomp_mask; } static inline void fpstate_init_fxstate(struct fxregs_state *fx) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 571220ac8bea..52f886477b07 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -192,8 +192,25 @@ static inline void fpstate_init_fstate(struct fregs_state *fp) fp->fos = 0xffff0000u; } -void fpstate_init(union fpregs_state *state) +/** + * + * fpstate_init() - initialize the xstate buffer + * + * If @fpu is NULL, initialize init_fpstate. + * + * @fpu: A struct fpu * pointer + * + * Returns nothing. + */ +void fpstate_init(struct fpu *fpu) { + union fpregs_state *state; + + if (likely(fpu)) + state = &fpu->state; + else + state = &init_fpstate; + if (!static_cpu_has(X86_FEATURE_FPU)) { fpstate_init_soft(&state->soft); return; @@ -202,7 +219,7 @@ void fpstate_init(union fpregs_state *state) memset(state, 0, fpu_kernel_xstate_size); if (static_cpu_has(X86_FEATURE_XSAVES)) - fpstate_init_xstate(&state->xsave); + fpstate_init_xstate(&state->xsave, xfeatures_mask_all); if (static_cpu_has(X86_FEATURE_FXSR)) fpstate_init_fxstate(&state->fxsave); else @@ -262,7 +279,7 @@ static void fpu__initialize(struct fpu *fpu) WARN_ON_FPU(fpu != ¤t->thread.fpu); set_thread_flag(TIF_NEED_FPU_LOAD); - fpstate_init(&fpu->state); + fpstate_init(fpu); trace_x86_fpu_init_state(fpu); } diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c index 701f196d7c68..74e03e3bc20f 100644 --- a/arch/x86/kernel/fpu/init.c +++ b/arch/x86/kernel/fpu/init.c @@ -124,7 +124,7 @@ static void __init fpu__init_system_generic(void) * Set up the legacy init FPU context. (xstate init might overwrite this * with a more modern format, if the CPU supports it.) */ - fpstate_init(&init_fpstate); + fpstate_init(NULL); fpu__init_system_mxcsr(); } diff --git a/arch/x86/kernel/fpu/regset.c b/arch/x86/kernel/fpu/regset.c index c413756ba89f..4c4d9059ff36 100644 --- a/arch/x86/kernel/fpu/regset.c +++ b/arch/x86/kernel/fpu/regset.c @@ -144,7 +144,7 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset, * In case of failure, mark all states as init: */ if (ret) - fpstate_init(&fpu->state); + fpstate_init(fpu); return ret; } diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index a85c64000218..767ad6b008c2 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -457,8 +457,7 @@ static void __init setup_init_fpu_buf(void) print_xstate_features(); if (boot_cpu_has(X86_FEATURE_XSAVES)) - init_fpstate.xsave.header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT | - xfeatures_mask_all; + fpstate_init_xstate(&init_fpstate.xsave, xfeatures_mask_all); /* * Init all the features state with header.xfeatures being 0x0 diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index bbc4e04e67ad..9af0a3c52b62 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -10248,7 +10248,7 @@ static void fx_init(struct kvm_vcpu *vcpu) if (!vcpu->arch.guest_fpu) return; - fpstate_init(&vcpu->arch.guest_fpu->state); + fpstate_init(vcpu->arch.guest_fpu); if (boot_cpu_has(X86_FEATURE_XSAVES)) vcpu->arch.guest_fpu->state.xsave.header.xcomp_bv = host_xcr0 | XSTATE_COMPACTION_ENABLED;