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 B7262C00145 for ; Mon, 12 Dec 2022 13:19:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232584AbiLLNTX (ORCPT ); Mon, 12 Dec 2022 08:19:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43624 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232707AbiLLNSu (ORCPT ); Mon, 12 Dec 2022 08:18:50 -0500 Received: from mail-yw1-x112b.google.com (mail-yw1-x112b.google.com [IPv6:2607:f8b0:4864:20::112b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9AA8813D06 for ; Mon, 12 Dec 2022 05:17:56 -0800 (PST) Received: by mail-yw1-x112b.google.com with SMTP id 00721157ae682-3bfd998fa53so144942087b3.5 for ; Mon, 12 Dec 2022 05:17:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=y7MvI0l6U01NL+JgWVWVhPKtCnV5a2AKEYcx/fldpjY=; b=eWLtylRDBk2dOZkHT6UlxUnpckauw8t+CToAP39TwpMZUkzVIVdRIzIW5TYnSSWYM2 rWZIIYnVy2icwTKmmmMpVVs03+bi8riOVfTbhfPzTKkgfsr/5NNGk5TnBIkeevGogdw7 YlPPtB1IIZZR4t9elJS3ux1rL7NLzCjw6hLysX3VqKwvkBuvs/bintm+f3UhB6rRe0H6 9GmeIQ/8tjn1/FOpTEFOhSdxQL7dFMFd0oXLNCQc8EA73ZglSJiJL1fBwkpxImAJ6HPU qabznTuvnjDbwio9q/oIJYmN1khfUNmQm7gQ7gDTBuYEwX4ypwEwxMiSd1GsEUxlywxJ gfJA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=y7MvI0l6U01NL+JgWVWVhPKtCnV5a2AKEYcx/fldpjY=; b=RT23W6MZrxOATtg27+EPH1CAAAHSrMuka/6Awzx+sfyGS1dhQmgIRjynZ3E5dX0dxW TRED+L7myl0yQV3wYY0LuhL+wlrU6FZ0B/i5qbfNcNdyqjpvQHAFTg7wtMLl5FlRm0TW 7uo3yqyA4VhWm4KkUsdQ2Lpq1AU7bDAG3QJO795CqHPGZ0mPjeDJk0p10vEAR4VGRBku f0gIlZzEK3nXjCaHggaBElzrzvAGaghbxbn86+kCsg77bcJdlcjx8dqY5Tipb5UoaXdn gEHdXXLtO9+n2FsS/TDvzRtcnfzYiRlndc3VMIZg3Kqi4LKcA7BANWdL6ygevlytEENf 9fyw== X-Gm-Message-State: ANoB5pkY5puQpmC9/M7e2MbV5GcbJOstRY4JlzmX497No7v1Os9MMmbX gP88R7JgXa1NFhQ+kNv4Cu9ONK9GzehCbanw X-Google-Smtp-Source: AA0mqf7fd/L7xUFraGI/lU35uHxXsrEZq4UJzo3P6d6uWEmmB5G4VFinTVCyVdcIyy6rL1ar2EnL7Q== X-Received: by 2002:a05:7500:1c4d:b0:ea:7e6b:1c36 with SMTP id dz13-20020a0575001c4d00b000ea7e6b1c36mr1151295gab.31.1670851075731; Mon, 12 Dec 2022 05:17:55 -0800 (PST) Received: from ziepe.ca (hlfxns017vw-142-68-50-193.dhcp-dynamic.fibreop.ns.bellaliant.net. [142.68.50.193]) by smtp.gmail.com with ESMTPSA id t30-20020a37ea1e000000b006eef13ef4c8sm5724075qkj.94.2022.12.12.05.17.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 12 Dec 2022 05:17:54 -0800 (PST) Received: from jgg by wakko with local (Exim 4.95) (envelope-from ) id 1p4igs-008dzE-6i; Mon, 12 Dec 2022 09:17:54 -0400 Date: Mon, 12 Dec 2022 09:17:54 -0400 From: Jason Gunthorpe To: Steven Sistare Cc: Alex Williamson , "Tian, Kevin" , "kvm@vger.kernel.org" Subject: Re: [PATCH] vfio/type1: Cleanup remaining vaddr removal/update fragments Message-ID: References: <167044909523.3885870.619291306425395938.stgit@omen> <20221208094008.1b79dd59.alex.williamson@redhat.com> <20221209124212.672b7a9c.alex.williamson@redhat.com> <5f494e1f-536d-7225-e2c7-5ec9c993f13a@oracle.com> <20221209140120.667cb658.alex.williamson@redhat.com> <6914b4eb-cd82-0c3e-6637-c7922092ef11@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6914b4eb-cd82-0c3e-6637-c7922092ef11@oracle.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Sat, Dec 10, 2022 at 09:14:06AM -0500, Steven Sistare wrote: > Thank you for your thoughtful response. Rather than debate the degree of > of vulnerability, I propose an alternate solution. The technical crux of > the matter is support for mediated devices. I'm not sure I'm convinced about that. It is easy to make problematic situations with mdevs, but that doesn't mean other cases don't exist too eg what happens if userspace suspends and then immediately does something to trigger a domain attachment? Doesn't it still deadlock the kernel? Honestly, I'm not sure I see the big deal, just don't backport these reverts to your disto kernel. Jason