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 90412C433EF for ; Thu, 16 Jun 2022 09:40:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1359783AbiFPJkM (ORCPT ); Thu, 16 Jun 2022 05:40:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34426 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359460AbiFPJkK (ORCPT ); Thu, 16 Jun 2022 05:40:10 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 194C559309 for ; Thu, 16 Jun 2022 02:40:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Xe7EVTVfA/LYwJX1fqIJNYg/fd5ZMqoScXc4Hw5xwQc=; b=oqFOhI9n/euMEb6yHqNMZXCtN+ JXj3RafSEAdQvbGKAHXQHOE5f56H8B1uBNQCQt6AA3+v7gxD+BD7jU+CrwBITfLkzM24eovGid8Tn E2S0CWp8H1z1zdhxQhiNsB8tABKSZsju3DBEgMWPPSgFKlsZ6ZsKKIh2qW3ESza3b0ImFSc/xl6/j ua4cNeuvFm0KeFDgwdK/V8lToG+myTHc336nOVpEdPm95Al4keI/ZqdTcgH1IdcrAJ9ggjxz9rmJK 0Iz4cVWuyHzHJ+L5sFDqA1W3vQ50sU/FvWuMwrFrzRf8/rxm3HYRH/CI5FdhAvm80wTnnnR9mhl8S 2cu+oXzA==; Received: from dhcp-077-249-017-003.chello.nl ([77.249.17.3] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1o1lyh-008Nh5-Mg; Thu, 16 Jun 2022 09:39:52 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id EDFFA300212; Thu, 16 Jun 2022 11:39:50 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id D7AFD2014ABD6; Thu, 16 Jun 2022 11:39:50 +0200 (CEST) Date: Thu, 16 Jun 2022 11:39:50 +0200 From: Peter Zijlstra To: "Kirill A. Shutemov" Cc: Dave Hansen , Andy Lutomirski , x86@kernel.org, Kostya Serebryany , Andrey Ryabinin , Andrey Konovalov , Alexander Potapenko , Dmitry Vyukov , "H . J . Lu" , Andi Kleen , Rick Edgecombe , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCHv3 6/8] x86/mm: Provide ARCH_GET_UNTAG_MASK and ARCH_ENABLE_TAGGED_ADDR Message-ID: References: <20220610143527.22974-1-kirill.shutemov@linux.intel.com> <20220610143527.22974-7-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220610143527.22974-7-kirill.shutemov@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 10, 2022 at 05:35:25PM +0300, Kirill A. Shutemov wrote: > Add a couple of arch_prctl() handles: > > - ARCH_ENABLE_TAGGED_ADDR enabled LAM. The argument is required number > of tag bits. It is rounded up to the nearest LAM mode that can > provide it. For now only LAM_U57 is supported, with 6 tag bits. As stated in the reply to the other patch; this isn't a 'for now' thing. Due to how the untag thing works. Supporting U48 on 5-level kernels is going to require a more complicated untag.