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=-8.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 75CF0C43461 for ; Thu, 10 Sep 2020 01:47:12 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EF107206B5 for ; Thu, 10 Sep 2020 01:47:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="hjFQViPn"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="u/iv2lgV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EF107206B5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=N2CCYp7PwNxSmeG2WW8ElectyxLdKdjnA/C/SqrNJG4=; b=hjFQViPn5OmAT6a2DCNyFT5OD 1b4Y8u2+hjG5ZTeAbFpLNAj7m6IrO+efo9Ghk24mzOKixV8oIr2ow8yM/jJzoEJWy4Q4zpf7Cdm08 IqAJJACJDtaNIezU7RGKaoqaUHw5Rpkg/8A2RvWUd2ZidouEeBewPT2T1/521g8ypBmaNIwIXKyPZ S5MjJYfvTSCBrGQw1DMFzJ/liAYr448GIlv/jaSTvvRNTaX8JIWADABvO2JbJj0kgF2GgMzVtJqtl 8ZC64gz1/GsUFnroH+B1KTodQHz0hp+ZsAsQcjmx4Xg1a5olhgb53LtzMwUxpTux9XB+/T5iuj28a ETnONJfeg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kGBeg-0006Px-27; Thu, 10 Sep 2020 01:45:42 +0000 Received: from mail-pf1-x444.google.com ([2607:f8b0:4864:20::444]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kGBed-0006Pc-6r for linux-arm-kernel@lists.infradead.org; Thu, 10 Sep 2020 01:45:40 +0000 Received: by mail-pf1-x444.google.com with SMTP id w7so3712025pfi.4 for ; Wed, 09 Sep 2020 18:45:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=srlzi6kO9KxXkI8QJDt5Z43HoR7v2ko9LYXQ8jt4y44=; b=u/iv2lgVycfu88AolfBLdcxoQkKwFXlBKbtJ8zj8UK6eoFLqKxQheAfb05BlbcjwKz G8IsBcKBAAda2DaUi0COUFu04Hgo/bR90dfH8TpuflZRaHnC1khAEnRbSFJQPHZdmbOU 52oCPFtp2JMMYx+7+DIob4TqY2CPbrFgfDAD4HYjqQ0FZNHOF9gB/q+C2Fs3bpOQg0YE hue7OYmW6G4eWQeXxXOT1y6I0qdgh2BpgOh4Ybit8LKhLF1Gi1vG2NHllpk0fVbF9hS8 f0vWsNBOavuocqCQkz3yBm5hrrBsPxXEPuV1wvG1Tk++5ZE9iciU1ZSfbVrnFoMcVRO7 rjYg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=srlzi6kO9KxXkI8QJDt5Z43HoR7v2ko9LYXQ8jt4y44=; b=s7R7ISz/SnItCPvCX45/Jf2gqojvEzfOxTkP485McyPuUBW002L0Pvm/O8q1IcM9iN 2C1mhiLjo+zPT7FYIBVTRFea9afoCQlCw5eY3VJHHYkt2U3iE5Mp4C5dLV8bgIKEu/VZ yGffaS69PpWGYz9vRa6FwsVZy8HQaXdFw9wTup9ZeJ8jkH6uPl6DCZchZcwpxNe1BDfW XI+VfqY+V+RVVEkXFzGHBhS0RWiDKn8Hix/Y+KZ2GI+8ZwhzknP3NIQaLGkDCzGQGTy5 ht96813Gs4KNdzLdZBBWM6VDkVBApcPJGJ/SS5woBmxJTw9gorqERTpwPgefskrxqkAa RDLQ== X-Gm-Message-State: AOAM530wjKGP1Jyw8NWzrwYVhrOVrsx2z2B5AJUD3PXkf27tYD+0FyZp E5Ql36B/CLiJZW5JvLfRWwe0pYOyaiKsnQ== X-Google-Smtp-Source: ABdhPJyqpWOeqHuTEIwwj1uDXktA1dBPRjOp1EaAUDe2coNSXU+KFMxtpo7uhsAAcumooCW0G+ElHQ== X-Received: by 2002:a62:b407:: with SMTP id h7mr3166747pfn.134.1599702336093; Wed, 09 Sep 2020 18:45:36 -0700 (PDT) Received: from [192.168.1.11] ([71.212.141.89]) by smtp.gmail.com with ESMTPSA id s20sm3936396pfu.112.2020.09.09.18.45.34 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 09 Sep 2020 18:45:35 -0700 (PDT) Subject: Re: [PATCH v2 0/2] MTE support for KVM guest To: Andrew Jones , Steven Price References: <20200904160018.29481-1-steven.price@arm.com> <20200909152540.ylnrljd6aelxoxrf@kamzik.brq.redhat.com> From: Richard Henderson Message-ID: <5cb1d7ed-54a5-4337-6c3d-2e3e7df89f17@linaro.org> Date: Wed, 9 Sep 2020 18:45:33 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200909152540.ylnrljd6aelxoxrf@kamzik.brq.redhat.com> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200909_214539_518485_5152FCF6 X-CRM114-Status: GOOD ( 16.62 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Maydell , Juan Quintela , Catalin Marinas , qemu-devel@nongnu.org, "Dr. David Alan Gilbert" , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Marc Zyngier , Thomas Gleixner , Will Deacon , Dave Martin , linux-kernel@vger.kernel.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 9/9/20 8:25 AM, Andrew Jones wrote: >> * Provide a KVM-specific method to extract the tags from guest memory. >> This might also have benefits in terms of providing an easy way to >> read bulk tag data from guest memory (since the LDGM instruction >> isn't available at EL0). > > Maybe we need a new version of KVM_GET_DIRTY_LOG that also provides > the tags for all addresses of each dirty page. KVM_GET_DIRTY_LOG just provides one bit per dirty page, no? Then VMM copies the data out from its local address to guest memory. There'd be no difference with or without tags, afaik. It's just about how VMM copies the data, with or without tags. >> * Provide support for user space setting the TCMA0 or TCMA1 bits in >> TCR_EL1. These would allow the VMM to generate pointers which are not >> tag checked. > > So this is necessary to allow the VMM to keep tag checking enabled for > itself, plus map guest memory as PROT_MTE, and write to that memory when > needed? I don't see a requirement for the VMM to set TCMA0. r~ _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel