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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 3D1F0C4321E for ; Mon, 10 Sep 2018 15:53:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E5BF620882 for ; Mon, 10 Sep 2018 15:53:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E5BF620882 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728309AbeIJUsV (ORCPT ); Mon, 10 Sep 2018 16:48:21 -0400 Received: from mx2.suse.de ([195.135.220.15]:44412 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727998AbeIJUsV (ORCPT ); Mon, 10 Sep 2018 16:48:21 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 19E3EAD72; Mon, 10 Sep 2018 15:53:37 +0000 (UTC) Date: Mon, 10 Sep 2018 17:53:29 +0200 From: Borislav Petkov To: Brijesh Singh Cc: x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Tom Lendacky , Thomas Gleixner , "H. Peter Anvin" , Paolo Bonzini , Sean Christopherson , Radim =?utf-8?B?S3LEjW3DocWZ?= Subject: Re: [PATCH v6 5/5] x86/kvm: Avoid dynamic allocation of pvclock data when SEV is active Message-ID: <20180910155329.GB20286@zn.tnic> References: <1536343050-18532-1-git-send-email-brijesh.singh@amd.com> <1536343050-18532-6-git-send-email-brijesh.singh@amd.com> <20180910122727.GE21815@zn.tnic> <026d5ca5-7b77-de6c-477e-ff39f0291ac0@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <026d5ca5-7b77-de6c-477e-ff39f0291ac0@amd.com> User-Agent: Mutt/1.9.5 (2018-04-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 10, 2018 at 08:15:38AM -0500, Brijesh Singh wrote: > > Now, the real question from all this SNAFU is, why can't all those point > > to a single struct pvclock_vsyscall_time_info and all CPUs read a single > > thing? Why do they have to be per-CPU and thus waste so much memory? You forgot to answer to the real question - why do we need those things to be perCPU and why can't we use a single instance to share with *all* CPUs? Because if we can, then we're golden! -- Regards/Gruss, Boris. SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg) --