From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.alien8.de (mail.alien8.de [65.109.113.108]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9DDEF4A0F for ; Mon, 1 Jul 2024 06:40:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=65.109.113.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719816027; cv=none; b=beejHVZz+972ybXT03CZVa1ENXR9ZkuJOURtNrUceBAw10n3AEdE8J7qT/vSGCKQ+8+BLpz6rs/bdPKIYefa1NfdG2QTH0cFVPny2HWOnaCgF6hdXGk0UVhZ6obWZF/0V3OdywNcqavzRFx8rPc4kLfYCxK+WdpUdw7Ujw9L3Ws= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719816027; c=relaxed/simple; bh=w/bD27FbT9dfXD0xVtt8O/vtTJE6hEYbgX0obX304/0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=s3artD84Vi1YDcxXIYySfs/I5o+WxHFJccvLqR1YtOcJNDXbzjvgUK59js3g1TuTrVB03JCkGgg7QOcArZuOH0JB1SQZmcDNM10m2YrJrv6AaDe2amxYvNg9f6QWNrducze63dphCAh842a93Jqdy7jM+0LTnFfRyfLyGwF5/v0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=alien8.de; spf=pass smtp.mailfrom=alien8.de; dkim=pass (4096-bit key) header.d=alien8.de header.i=@alien8.de header.b=FjuzUt4x; arc=none smtp.client-ip=65.109.113.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=alien8.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=alien8.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (4096-bit key) header.d=alien8.de header.i=@alien8.de header.b="FjuzUt4x" Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with ESMTP id 3463840E021F; Mon, 1 Jul 2024 06:40:23 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at mail.alien8.de Authentication-Results: mail.alien8.de (amavisd-new); dkim=pass (4096-bit key) header.d=alien8.de Received: from mail.alien8.de ([127.0.0.1]) by localhost (mail.alien8.de [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id kDMs4mNFRqVZ; Mon, 1 Jul 2024 06:40:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=alien8; t=1719816020; bh=uNPW7RWvc4Gi05J3X2xFF1c8MpeXPWJhF4rBi+qDDxI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=FjuzUt4x5qCBi/K4DaljMHytND6Dyjb9ueyXpmz7i5IVu19+k66CxmZosAP/Rf5Zb m0NZ5gy9rDqCeV6ownVVND2XP3W9Mvsig4APlDibTPcELsxcf1RwkkE5X6ukL0AMn5 ZCjLTHGnbzrVyndfPifJiZaRb15dE88uVa/Q4onFFAiM4qlCtl6+jC15HNy+9nBUwO B1v2nzDIUeyQRBHKfjSEHeYruvjErW69Jm9eKsPMn0H3rB7nG7AYgY+74CYRtVz0aH UKDdc1lqchOVMWTPogjSJ+2cNAyh9OBH/ccHuP6ylEC79SPo2swv35+r1HLdgEmpr4 d3UGd+k7EeC4J1Qns23SfsdWS6koJ08sDCrI6bDGHrZIP56/1ca1cUqvcGsdaL4kKC W8VE+Tw1ta+HAwTLixXTiRLX6gYrDfbto9dpCk1hGeQ7+KXVWvstqIKiuWOyk2BhkQ yFVIFslQFAJkdxcLPMw+QWRlQIOAcfwbtrfwOwjuiUsRGSztXiTJEb6lHf13AZVpYZ WqpKK0Ayi6DqU6lwUXMP/L/b31d3drOhLT1tU2ibkngxW/85lnKbCvS6dRtKeV7D53 bVymBZE7mHVdzy4Zt5BQRglZp1AJTrd8zDWegbnuAQnuiqkwCyAdX854qE79B7pwdO pZsV+Xu/j/ac09DjXpWCT+O0= Received: from zn.tnic (p5de8ee85.dip0.t-ipconnect.de [93.232.238.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 0D8B540E021B; Mon, 1 Jul 2024 06:40:09 +0000 (UTC) Date: Mon, 1 Jul 2024 08:40:02 +0200 From: Borislav Petkov To: "H. Peter Anvin" Cc: Xin Li , linux-kernel@vger.kernel.org, x86@kernel.org, tglx@linutronix.de, mingo@redhat.com, dave.hansen@linux.intel.com, peterz@infradead.org, brgerst@gmail.com, chang.seok.bae@intel.com, jgross@suse.com Subject: Re: [PATCH v6 5/5] x86/gsseg: use the LKGS instruction if available for load_gs_index() Message-ID: <20240701064002.GBZoJPQg2IXSCRa4sN@fat_crate.local> References: <20230112072032.35626-1-xin3.li@intel.com> <20230112072032.35626-6-xin3.li@intel.com> <20240630160448.GAZoGCIHXRuBY8sLqW@fat_crate.local> <3A846C73-305E-4C55-B846-AC00657BA95B@zytor.com> <20240701060841.GAZoJH6XpJz6qyo-Lr@fat_crate.local> <38C69EA0-DB74-4D2A-ABB5-CB3F1D31FB0C@zytor.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <38C69EA0-DB74-4D2A-ABB5-CB3F1D31FB0C@zytor.com> On Sun, Jun 30, 2024 at 11:31:42PM -0700, H. Peter Anvin wrote: > Yes, all loads into a segment register are truncated to 16 bits. Right, but are we saying that somewhere explicitly or it is too obvious so that there's no need to? -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette