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 57B41C54EBD for ; Thu, 12 Jan 2023 07:44:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239348AbjALHoh (ORCPT ); Thu, 12 Jan 2023 02:44:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60536 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238542AbjALHoY (ORCPT ); Thu, 12 Jan 2023 02:44:24 -0500 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6542540868 for ; Wed, 11 Jan 2023 23:44:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1673509463; x=1705045463; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=OY4mJD00oqqr2RtKHljKwaZ/6wONtTTVjhA0Ev1fnaU=; b=gc/JXR5ld2zLsbie2G+7xlg9QHANKReSHrb58iuWOZWXq5ROfqNJuAGn MexNFnCMACaODP5QL+1hm0FzwSYeWdvgiZEtVPeG6z6o0JaWONAHCn6/a wDdHwFQ5jZVE/yD8jhHVt5+W0HoaRfwxaeH5zFGeEW4xfyBRZcCjG/CF8 uBenFzEa4JTKgWiZEbIfiSX4zjiTZjHHWBys4xk0l8kLCb0rXKT05qtQv UMNsxPukwCKBO9V/EzE1ATLsRbTSGQp3hBWdAXeeUjiSRUF0FlTgLA9/i fJW++FJ5IuxJho1hrHKUT6718jOyVhRRoTcMi73nxpSb/uajc97k0oRrZ w==; X-IronPort-AV: E=McAfee;i="6500,9779,10586"; a="321328696" X-IronPort-AV: E=Sophos;i="5.96,319,1665471600"; d="scan'208";a="321328696" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jan 2023 23:44:23 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10586"; a="635283951" X-IronPort-AV: E=Sophos;i="5.96,319,1665471600"; d="scan'208";a="635283951" Received: from unknown (HELO fred..) ([172.25.112.68]) by orsmga006.jf.intel.com with ESMTP; 11 Jan 2023 23:44:22 -0800 From: Xin Li To: linux-kernel@vger.kernel.org, x86@kernel.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, peterz@infradead.org, brgerst@gmail.com, chang.seok.bae@intel.com, jgross@suse.com Subject: [PATCH v6 3/5] x86/gsseg: make asm_load_gs_index() take an u16 Date: Wed, 11 Jan 2023 23:20:30 -0800 Message-Id: <20230112072032.35626-4-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230112072032.35626-1-xin3.li@intel.com> References: <20230112072032.35626-1-xin3.li@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "H. Peter Anvin (Intel)" Let gcc know that only the low 16 bits of load_gs_index() argument actually matter. It might allow it to create slightly better code. However, do not propagate this into the prototypes of functions that end up being paravirtualized, to avoid unnecessary changes. Signed-off-by: H. Peter Anvin (Intel) Signed-off-by: Xin Li --- arch/x86/entry/entry_64.S | 2 +- arch/x86/include/asm/special_insns.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 15739a2c0983..7ecd2aeeeffc 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -782,7 +782,7 @@ _ASM_NOKPROBE(common_interrupt_return) /* * Reload gs selector with exception handling - * edi: new selector + * di: new selector * * Is in entry.text as it shouldn't be instrumented. */ diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h index 35f709f619fb..a71d0e8d4684 100644 --- a/arch/x86/include/asm/special_insns.h +++ b/arch/x86/include/asm/special_insns.h @@ -120,7 +120,7 @@ static inline void native_wbinvd(void) asm volatile("wbinvd": : :"memory"); } -extern asmlinkage void asm_load_gs_index(unsigned int selector); +extern asmlinkage void asm_load_gs_index(u16 selector); static inline void native_load_gs_index(unsigned int selector) { -- 2.34.1