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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 9EECDC48BD3 for ; Wed, 26 Jun 2019 18:22:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 744A221726 for ; Wed, 26 Jun 2019 18:22:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561573332; bh=RCUZ20s+FO/ACLr0Oia7zO1LHuxkGngcQaAh4XmHjFw=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=Krck/wVuSiDI+ycsIOTLslek62xliODnmXHqyQg39oDD8cK9wIRs8652paRd9xA53 7vKQ2AHa5nh1Na9TQhxR0SHBbYK3FzR9QlvlO86zvu7sGzw0LDOjWojQIyKHEcJc/A Rlo+F+taWwOHrFjh+PIFMPMV6uGVCuxeK4sEgGp8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726503AbfFZSWJ (ORCPT ); Wed, 26 Jun 2019 14:22:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:36488 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726223AbfFZSWJ (ORCPT ); Wed, 26 Jun 2019 14:22:09 -0400 Received: from mail-wr1-f50.google.com (mail-wr1-f50.google.com [209.85.221.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3F7782182B for ; Wed, 26 Jun 2019 18:22:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561573328; bh=RCUZ20s+FO/ACLr0Oia7zO1LHuxkGngcQaAh4XmHjFw=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=DWcrF2jASB5Nyc7Lay2ty4eigHh4hjHhsAgxAEAt38NGI3MQAtToTRiyul2ItRjlz yANgdkyXusdbSXn2GZFy6vSFJeJO8l26MDk9Gru27/ICyAhi44mIwUdMGx0yMR+RbD s5bXkxxmOjSjFyuORb180Urq3qgMEngzxN7sd6GY= Received: by mail-wr1-f50.google.com with SMTP id d18so3853258wrs.5 for ; Wed, 26 Jun 2019 11:22:08 -0700 (PDT) X-Gm-Message-State: APjAAAWTCZl5ycLhOYZGWDjHHTNs/plB2IuGZElq4qINvNHELjwyJs6+ zNUFxxIUvg6TgdKlgvyPRlUKNCQ5VsSq9Rm2g9+Izw== X-Google-Smtp-Source: APXvYqzBxY4A3/fHzFsZp/lckxSB2259/DoEQvS3DVOHEjr3/bNQHVWVcK4ly/vBTttvpRhufA67lVArmUoWdpgsxMg= X-Received: by 2002:adf:f28a:: with SMTP id k10mr4920678wro.343.1561573326724; Wed, 26 Jun 2019 11:22:06 -0700 (PDT) MIME-Version: 1.0 References: <20190613064813.8102-1-namit@vmware.com> <20190613064813.8102-7-namit@vmware.com> <401C4384-98A1-4C27-8F71-4848F4B4A440@vmware.com> <35755C67-E8EB-48C3-8343-BB9ABEB4E32C@vmware.com> <878stockhi.fsf@vitty.brq.redhat.com> In-Reply-To: <878stockhi.fsf@vitty.brq.redhat.com> From: Andy Lutomirski Date: Wed, 26 Jun 2019 11:21:54 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 6/9] KVM: x86: Provide paravirtualized flush_tlb_multi() To: Vitaly Kuznetsov Cc: Andy Lutomirski , Nadav Amit , Dave Hansen , Peter Zijlstra , LKML , Ingo Molnar , Borislav Petkov , "the arch/x86 maintainers" , Thomas Gleixner , Dave Hansen , Paolo Bonzini , "kvm@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 26, 2019 at 10:41 AM Vitaly Kuznetsov wrote: > > Andy Lutomirski writes: > > > All this being said, do we currently have any system that supports > > PCID *and* remote flushes? I guess KVM has some mechanism, but I'm > > not that familiar with its exact capabilities. If I remember right, > > Hyper-V doesn't expose PCID yet. > > > > It already does (and support it to certain extent), see > > commit 617ab45c9a8900e64a78b43696c02598b8cad68b > Author: Vitaly Kuznetsov > Date: Wed Jan 24 11:36:29 2018 +0100 > > x86/hyperv: Stop suppressing X86_FEATURE_PCID > Hmm. Once the dust settles from Nadav's patches, I think we should see about supporting it better :)