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 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 E6B7AC47080 for ; Sun, 23 May 2021 19:39:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C97E26117A for ; Sun, 23 May 2021 19:39:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232229AbhEWTlQ (ORCPT ); Sun, 23 May 2021 15:41:16 -0400 Received: from mga07.intel.com ([134.134.136.100]:12053 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232008AbhEWTj6 (ORCPT ); Sun, 23 May 2021 15:39:58 -0400 IronPort-SDR: nkonRLIllWwntV5nkB6gZQuaQJPOncqD/ZGh+YD2jPugw1vDIdi9JyP2ojsu0aRanFxfiq7uuS pfqu1bQO9s8A== X-IronPort-AV: E=McAfee;i="6200,9189,9993"; a="265703542" X-IronPort-AV: E=Sophos;i="5.82,319,1613462400"; d="scan'208";a="265703542" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 May 2021 12:38:29 -0700 IronPort-SDR: tUM0pKVM27xRAXG8u26u4vbDMpLxX5nHr3zH2rBpsUUBTqZ1T1r9tSmXGdaWD+eHhprO4jumQM cs8FZV2+4b8g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,319,1613462400"; d="scan'208";a="407467126" Received: from chang-linux-3.sc.intel.com ([172.25.66.175]) by fmsmga007.fm.intel.com with ESMTP; 23 May 2021 12:38:29 -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 Subject: [PATCH v5 21/28] x86/fpu/amx: Initialize child's AMX state Date: Sun, 23 May 2021 12:32:52 -0700 Message-Id: <20210523193259.26200-22-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: linux-kernel@vger.kernel.org Assure that a forked child starts AMX registers in the INIT-state. Signed-off-by: Chang S. Bae Reviewed-by: Len Brown Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org --- Changes from v4: * Added as a new patch. This was missing on previous versions. --- arch/x86/kernel/fpu/core.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 016c3adebec3..cccfeafe81e5 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -285,6 +285,10 @@ int fpu__copy(struct task_struct *dst, struct task_struct *src) fpregs_unlock(); + /* AMX state is volatile, children do not inherit it. */ + if (xfeatures_mask_all & XFEATURE_MASK_XTILE) + dst_fpu->state->xsave.header.xfeatures &= ~(XFEATURE_MASK_XTILE); + set_tsk_thread_flag(dst, TIF_NEED_FPU_LOAD); trace_x86_fpu_copy_src(src_fpu); -- 2.17.1