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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 08A6EC433F5 for ; Fri, 1 Oct 2021 22:45:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E448A61AF7 for ; Fri, 1 Oct 2021 22:45:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356166AbhJAWrl (ORCPT ); Fri, 1 Oct 2021 18:47:41 -0400 Received: from mga17.intel.com ([192.55.52.151]:38078 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356219AbhJAWrI (ORCPT ); Fri, 1 Oct 2021 18:47:08 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10124"; a="205756666" X-IronPort-AV: E=Sophos;i="5.85,340,1624345200"; d="scan'208";a="205756666" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Oct 2021 15:44:23 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.85,340,1624345200"; d="scan'208";a="565344013" Received: from chang-linux-3.sc.intel.com ([172.25.66.175]) by fmsmga002.fm.intel.com with ESMTP; 01 Oct 2021 15:44:18 -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, lenb@kernel.org, dave.hansen@intel.com, thiago.macieira@intel.com, jing2.liu@intel.com, ravi.v.shankar@intel.com, linux-kernel@vger.kernel.org, chang.seok.bae@intel.com Subject: [PATCH v11 21/29] x86/fpu/amx: Initialize child's AMX state Date: Fri, 1 Oct 2021 15:37:20 -0700 Message-Id: <20211001223728.9309-22-chang.seok.bae@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211001223728.9309-1-chang.seok.bae@intel.com> References: <20211001223728.9309-1-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 v5: * Introduced a new define. (Andy Lutomirski) Changes from v4: * Added as a new patch. This was missing on previous versions. --- arch/x86/include/asm/fpu/xstate.h | 3 +++ arch/x86/kernel/fpu/core.c | 3 +++ 2 files changed, 6 insertions(+) diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h index e3d431e04bbf..0e355dfe711b 100644 --- a/arch/x86/include/asm/fpu/xstate.h +++ b/arch/x86/include/asm/fpu/xstate.h @@ -85,6 +85,9 @@ XFEATURE_MASK_INDEPENDENT | \ XFEATURE_MASK_SUPERVISOR_UNSUPPORTED) +/* Volatile states that a child does not inherit. */ +#define XFEATURE_MASK_CLEARED_ON_CLONE XFEATURE_MASK_XTILE + #ifdef CONFIG_X86_64 #define REX_PREFIX "0x48, " #else diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index b722360d2a85..fdac0f430af3 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -300,6 +300,9 @@ int fpu_clone(struct task_struct *dst) save_fpregs_to_fpstate(dst_fpu); fpregs_unlock(); + if (xfeatures_mask_all & XFEATURE_MASK_CLEARED_ON_CLONE) + dst_fpu->state->xsave.header.xfeatures &= ~XFEATURE_MASK_CLEARED_ON_CLONE; + set_tsk_thread_flag(dst, TIF_NEED_FPU_LOAD); trace_x86_fpu_copy_src(src_fpu); -- 2.17.1