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=-12.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, 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 2E686C433DB for ; Wed, 24 Feb 2021 11:13:55 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 C51E264E83 for ; Wed, 24 Feb 2021 11:13:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C51E264E83 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.89270.168036 (Exim 4.92) (envelope-from ) id 1lEs6v-000513-On; Wed, 24 Feb 2021 11:13:41 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 89270.168036; Wed, 24 Feb 2021 11:13:41 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lEs6v-00050w-Lb; Wed, 24 Feb 2021 11:13:41 +0000 Received: by outflank-mailman (input) for mailman id 89270; Wed, 24 Feb 2021 11:13:39 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lEs6t-00050r-QA for xen-devel@lists.xenproject.org; Wed, 24 Feb 2021 11:13:39 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 5b5dbc4d-3514-436c-978b-5f2e3512683d; Wed, 24 Feb 2021 11:13:38 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 017D7ADF0; Wed, 24 Feb 2021 11:13:38 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 5b5dbc4d-3514-436c-978b-5f2e3512683d X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1614165218; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=KVtRyWlNUTJ6sD30gcEEEJyG/aGwIaj9/tz5k+zVB4o=; b=bKP2ap80OjqOSblZVfzc7nX+BO6zQbNEWsreU0QPE0xngWDnvW2/BxHbm4vqJ0x/D7XDBG ITwzPS4JuCu78dK7jnOAL0fzOGmqFbOFoc73iy/exhAPShRfVNSCuLiZ5s6HNh831A0Qz8 HdVu1q/sDbCOaiWmAsBg7/3CGFrgnqg= Subject: Re: [PATCH v2 0/8] x86/PV: avoid speculation abuse through guest accessors To: Ian Jackson Cc: "xen-devel@lists.xenproject.org" , Andrew Cooper , Wei Liu , =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= , George Dunlap References: <24623.56913.290437.499946@mariner.uk.xensource.com> From: Jan Beulich Message-ID: Date: Wed, 24 Feb 2021 12:13:37 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <24623.56913.290437.499946@mariner.uk.xensource.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit On 19.02.2021 16:50, Ian Jackson wrote: > Jan Beulich writes ("[PATCH v2 0/8] x86/PV: avoid speculation abuse through guest accessors"): >> Re-sending primarily for the purpose of getting a release ack, an >> explicit release nak, or an indication of there not being a need, >> all for at least the first three patches here (which are otherwise >> ready to go in). I've dropped the shadow part of the series from >> this re-submission, because it has all got reviewed by Tim already >> and is intended for 4.16 only anyway. I'm re-including the follow >> up patches getting the code base in consistent shape again, as I >> continue to think this consistency goal is at least worth a >> consideration towards a freeze exception. >> >> 1: split __{get,put}_user() into "guest" and "unsafe" variants >> 2: split __copy_{from,to}_user() into "guest" and "unsafe" variants >> 3: PV: harden guest memory accesses against speculative abuse > > These three: > > Release-Acked-by: Ian Jackson > > On the grounds that this is probably severe enough to be a blocking > issue for 4.15. > >> 4: rename {get,put}_user() to {get,put}_guest() >> 5: gdbsx: convert "user" to "guest" accesses >> 6: rename copy_{from,to}_user() to copy_{from,to}_guest_pv() >> 7: move stac()/clac() from {get,put}_unsafe_asm() ... >> 8: PV: use get_unsafe() instead of copy_from_unsafe() > > These have not got a maintainer review yet. To grant a release-ack > I'd like an explanation of the downsides and upsides of taking this > series in 4.15 ? > > You say "consistency" but in practical terms, what will happen if the > code is not "conxistent" in this sense ? > > I'd also like to hear from aother hypervisor maintainer. Meanwhile they have been reviewed by Roger. Are you willing to give them, perhaps with the exception of 7, a release ack as well? Jan