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=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 C65A8C3F2D1 for ; Thu, 5 Mar 2020 15:49:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9FE1A208CD for ; Thu, 5 Mar 2020 15:49:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="CRKLx0er" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726846AbgCEPtV (ORCPT ); Thu, 5 Mar 2020 10:49:21 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:20253 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726111AbgCEPtU (ORCPT ); Thu, 5 Mar 2020 10:49:20 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1583423359; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=cXuIpqJI7rTjh/BFJajlRtBWEXkuawKoUjndvA3VFKA=; b=CRKLx0erMM3FIe8+jeAFxh1Ca14RtpnfFIJCdbwQ4KzLItypjM8Fglj/Gz6hUcncoMcwM7 FnxXVMEbVyWKfjrAGKF1JyVO0jtIFOrantLdllzWxsX9A9JiF4erYQ0ZcfIqx/fNsq1zNX jGkZY8UxjXwd4ix9jVeIx1BN7bWH6Sw= Received: from mail-qv1-f69.google.com (mail-qv1-f69.google.com [209.85.219.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-363-MaAjaO6YPP-QBKpCYzAO_A-1; Thu, 05 Mar 2020 10:49:18 -0500 X-MC-Unique: MaAjaO6YPP-QBKpCYzAO_A-1 Received: by mail-qv1-f69.google.com with SMTP id dr18so3266982qvb.14 for ; Thu, 05 Mar 2020 07:49:18 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=cXuIpqJI7rTjh/BFJajlRtBWEXkuawKoUjndvA3VFKA=; b=nVBmFDCdJI7Gb5BEi39EpmIs1QQ0LytF92okcWGy9IcPq7bCVxMX1JQyY29DjLdWyB VQGPCl5oT3w7FF/O89G2a9gv24WAvK4Pnnf+WoKEffF31OvY2ptMe1xhx860tTWzEPMU 5D01q7M7asbAERLVsHtnuZTaL8VKDtCkdZKhqARpZQAT/qFVd/Y/VjD8BD/M0MQB4EoA 5EO5hfEoVqhCJ5JoFT5W/wGPJkbqx3FRI+hiwT27I92N7F9Voi41dKcvonAJbpa1NINa ySscOKy7EyZTQ+MzoVp8u2x/Pg+uVsnm9FMQ4XJAi7MOjorfpB5jetjUN4rPeAo4BOMs FY3w== X-Gm-Message-State: ANhLgQ1952OQl+1nVn0Dqi9Y9jD7G2IwRfG6XeznUnnf+dEuFWMpNL65 GcNpIj+yi4V/ibtzLXgKYCteD54o+2Nlvjwq+3InOcbh5bUp7FQZhGlFE1oNaTh3x78ROlg9dNt dqDfm7tqGqnaP X-Received: by 2002:ad4:480f:: with SMTP id g15mr6888251qvy.247.1583423357346; Thu, 05 Mar 2020 07:49:17 -0800 (PST) X-Google-Smtp-Source: ADFU+vughxL1Zr78oB78siwCRXuDqPRslu3YgV7DyjXfzDStD9FiLos09QdINXSzciM7YTSBPMwNVA== X-Received: by 2002:ad4:480f:: with SMTP id g15mr6888224qvy.247.1583423356972; Thu, 05 Mar 2020 07:49:16 -0800 (PST) Received: from xz-x1 ([2607:9880:19c0:32::2]) by smtp.gmail.com with ESMTPSA id s56sm310900qtk.9.2020.03.05.07.49.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 Mar 2020 07:49:16 -0800 (PST) Date: Thu, 5 Mar 2020 10:49:14 -0500 From: Peter Xu To: linmiaohe Cc: Paolo Bonzini , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" Subject: Re: [PATCH] KVM: Drop gfn_to_pfn_atomic() Message-ID: <20200305154914.GE7146@xz-x1> References: <2256821e496c45f5baf97f3f8f884d59@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <2256821e496c45f5baf97f3f8f884d59@huawei.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Mar 05, 2020 at 01:52:24AM +0000, linmiaohe wrote: > Peter Xu writes: > >It's never used anywhere now. > > > >Signed-off-by: Peter Xu > >--- > > include/linux/kvm_host.h | 1 - > > virt/kvm/kvm_main.c | 6 ------ > > 2 files changed, 7 deletions(-) > > It seems we prefer to use kvm_vcpu_gfn_to_pfn_atomic instead now. :) > Patch looks good, but maybe we should update Documentation/virt/kvm/locking.rst too: > In locking.rst: > For direct sp, we can easily avoid it since the spte of direct sp is fixed > to gfn. For indirect sp, before we do cmpxchg, we call gfn_to_pfn_atomic() > to pin gfn to pfn, because after gfn_to_pfn_atomic() > > Thanks. > Reviewed-by: Miaohe Lin Yes we should update the document, however instead of replacing with the vcpu helper, I'd rather reorganize the locking doc for a bit more because the fast page fault is not enabled for indirect sp at all, afaict... I'll add a pre-requisite patch to refine the document, and keep your r-b for this patch. Thanks, -- Peter Xu