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=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 D12F4C433DF for ; Mon, 8 Jun 2020 17:09:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A7CE92078D for ; Mon, 8 Jun 2020 17:09:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="p1wdQUod" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387409AbgFHRJ3 (ORCPT ); Mon, 8 Jun 2020 13:09:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730681AbgFHRJ2 (ORCPT ); Mon, 8 Jun 2020 13:09:28 -0400 Received: from mail-wm1-x344.google.com (mail-wm1-x344.google.com [IPv6:2a00:1450:4864:20::344]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F881C08C5C2 for ; Mon, 8 Jun 2020 10:09:27 -0700 (PDT) Received: by mail-wm1-x344.google.com with SMTP id j198so455588wmj.0 for ; Mon, 08 Jun 2020 10:09:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=O5kyIIzxsOCQ0wtFJtMJAdBIg3y6KuYFhCf9iMzgFJQ=; b=p1wdQUodkbKA53RU829/S14bgNwXUZk4oaZTZITlLvC1R/7pCLt8Qec1xAGFhamIuc 6GF1n0XpMYAVGZKMywm22h1ALDMPKC6G/E5cO+DrxJ5qCSzcWyrUHMqFumgbHdUB4PKI NXGPYjtcPBb58hKLeEFKZhEW3c+c7gfIsbHDkzXKT86fv2c6LRGCjIStT6NFcC/RFCUV Cd6FPlkFGwdFBPcY9Gu+WoR99u+T8tOtU2rKJ8OttEpNZZcKTZiS/TQdIyt7UoWh0mnL jSWwEg9ye92wgPswhOn2ZJsE21UwfoMC1vNYT56fDTeseRBdlyb87eNnOHq3gueSJbtm +Z4w== 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=O5kyIIzxsOCQ0wtFJtMJAdBIg3y6KuYFhCf9iMzgFJQ=; b=orj7XTEfutbE1qX7f76Wd6gDe59AIgwe0MnTfQ0jVbx4xvM7WhkMr6dEa7KFf9G0uI UUusoni5aSsSRnjTOEhTGgI1y8n1VsORlmya89YtiZ38cfjUNEGGykPq+5vfOds33Gho h1akvrvJ11zt4K+e0trhrtCcumpw+gf7bXU1bki1QDdxFHLaDTjr0MBMj1SgZIRZzSEn WEkBpZMIHnbIqzwAKq+NVfQqGFtJV0Q2DDUCy4gHtIwwbM41GH++CpKGfZSLE9B9O+yX noW18LKicxbzmkCcwFZVpOLYCp02Ukx15JCf6D9rsKQj/P1AXDZU1xk5IYBIf4JsVRV/ plfQ== X-Gm-Message-State: AOAM5333kGvKsYu3qHHEVNTu/0MiSe3AJ350aOWzMw18X7NiwdUhuaQe kgU2hysxW3XdH6WWN5hyrKcqTA== X-Google-Smtp-Source: ABdhPJxZEDJueTXgTcDW9U9iUaISMszgUVW6R1TTHIBvERHVRmV8seKAaqqSKuvHuMRooFnwn0NlQQ== X-Received: by 2002:a7b:cc08:: with SMTP id f8mr350455wmh.106.1591636165854; Mon, 08 Jun 2020 10:09:25 -0700 (PDT) Received: from google.com ([2a00:79e0:d:109:355c:447d:ad3d:ac5c]) by smtp.gmail.com with ESMTPSA id z8sm357180wru.33.2020.06.08.10.09.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 08 Jun 2020 10:09:25 -0700 (PDT) Date: Mon, 8 Jun 2020 18:09:20 +0100 From: Andrew Scull To: Marc Zyngier Cc: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, James Morse , Julien Thierry , Suzuki K Poulose , Mark Rutland , kernel-team@android.com Subject: Re: [PATCH v2] KVM: arm64: Remove host_cpu_context member from vcpu structure Message-ID: <20200608170920.GC96714@google.com> References: <20200608085657.1405730-1-maz@kernel.org> <20200608145145.GA96714@google.com> <1a00887a4af019fa83380b68afd43a29@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1a00887a4af019fa83380b68afd43a29@kernel.org> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Mon, Jun 08, 2020 at 04:42:42PM +0100, Marc Zyngier wrote: > Hi Andrew, > > On 2020-06-08 15:51, Andrew Scull wrote: > > On Mon, Jun 08, 2020 at 09:56:57AM +0100, Marc Zyngier wrote: > > > For very long, we have kept this pointer back to the per-cpu > > > host state, despite having working per-cpu accessors at EL2 > > > for some time now. > > > > > > Recent investigations have shown that this pointer is easy > > > to abuse in preemptible context, which is a sure sign that > > > it would better be gone. Not to mention that a per-cpu > > > pointer is faster to access at all times. > > > > Helps to make the references to `kvm_host_data` clearer with there now > > being just one way to get to it and shows that it is scoped to the > > current CPU. A good change IMO! > > Thanks! Can I take this as a Reviewed-by or Acked-by tag? Just let me know. Build and booted your kvm-arm64/ptrauth-fixes branch contianing this patch with VHE and nVHE on qemu. Booted a VM within each with kvmtool. Reviewed-by: Andrew Scull