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=-1.0 required=3.0 tests=MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 2D172CA9EAF for ; Mon, 21 Oct 2019 13:59:32 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id AD28C214B2 for ; Mon, 21 Oct 2019 13:59:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AD28C214B2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 10B9B4A9F3; Mon, 21 Oct 2019 09:59:31 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id f5bfnMWKsYcS; Mon, 21 Oct 2019 09:59:30 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 0CC644A9D9; Mon, 21 Oct 2019 09:59:30 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 016B44A9B6 for ; Mon, 21 Oct 2019 09:59:29 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id FUz1hN6GVn5w for ; Mon, 21 Oct 2019 09:59:27 -0400 (EDT) Received: from inca-roads.misterjones.org (inca-roads.misterjones.org [213.251.177.50]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id C8D044A9AE for ; Mon, 21 Oct 2019 09:59:27 -0400 (EDT) Received: from www-data by cheepnis.misterjones.org with local (Exim 4.80) (envelope-from ) id 1iMYDV-0004zv-5h; Mon, 21 Oct 2019 15:59:25 +0200 To: Christoffer Dall Subject: Re: [PATCH v3 0/2] Improve handling of stage 2 aborts without instruction decode X-PHP-Originating-Script: 0:main.inc MIME-Version: 1.0 Date: Mon, 21 Oct 2019 14:59:24 +0100 From: Marc Zyngier In-Reply-To: <20191021133707.GA2652@e113682-lin.lund.arm.com> References: <20191011110709.2764-1-christoffer.dall@arm.com> <865zkjzpbf.wl-maz@kernel.org> <20191021133707.GA2652@e113682-lin.lund.arm.com> Message-ID: <3ba9db99efaadd8c9372708358da0ac6@www.loen.fr> X-Sender: maz@kernel.org User-Agent: Roundcube Webmail/0.7.2 X-SA-Exim-Connect-IP: X-SA-Exim-Rcpt-To: christoffer.dall@arm.com, kvmarm@lists.cs.columbia.edu, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, linux-arm-kernel@lists.infradead.org, graf@amazon.com, berrange@redhat.com, xypron.glpk@gmx.de, stefanha@redhat.com, peter.maydell@linaro.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on cheepnis.misterjones.org); SAEximRunCond expanded to false Cc: =?UTF-8?Q?=22Daniel_P=2E_Berrang=C3=A9=22?= , Heinrich Schuchardt , Stefan Hajnoczi , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu On 2019-10-21 14:37, Christoffer Dall wrote: > On Sun, Oct 20, 2019 at 11:25:24AM +0100, Marc Zyngier wrote: >> Hi Christoffer, >> >> On Fri, 11 Oct 2019 12:07:04 +0100, >> Christoffer Dall wrote: >> > >> > When a guest accesses memory outside the memory slots, KVM usually >> > bounces the access back to userspace with KVM_EXIT_MMIO. However, >> on >> > arm/arm64 systems, certain load/store instructions did not provide >> > decoding info for the hypervisor to emulate the instruction, and >> in this >> > case KVM has rather rudely returned -ENOSYS and printed a not >> overly >> > helpful error message: >> > >> > load/store instruction decoding not implemented >> > >> > This patch series improves the error message and allows userspace >> to be >> > notified of this event instead of receiving -ENOSYS, and also >> allows >> > userspace to ask KVM to inject an external abort to the guest, >> which it >> > can use for any memory access that it either cannot handle. >> > >> > One remaining case which this patch set does not address is if the >> guest >> > accesses an in-kernel emulated device, such as the VGIC, but using >> a >> > load/store instruction which doesn't provide decode info. With >> these >> > patches, this will return to userspace for it to handle, but >> there's no >> > way for userspace to return the decoding information to KVM and >> have KVM >> > complete the access to the in-kernel emulated device. I have no >> plans >> > to address this limitation. >> >> You had some pending comments on patch 2, and you seem to indicate >> that you would respin the series. Do you have plans to do so in the >> coming days? I'd like to put that series into -next, but I can >> either >> wait for your respin, or queue it as it is and apply fixes on top. >> > > I think those for v2 and this is v3 which should address those > concerns. > Did I miss something or manage to confuse mysel here? Gah! No, it looks like the mistake is mine. I've mixed the two series in my Inbox, and the result is a total brain-fart. Ignore me. I'll queue these patches ASAP. Thanks, M. -- Jazz is not dead. It just smells funny... _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm 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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 814C8CA9EAF for ; Mon, 21 Oct 2019 13:59:39 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 510B32166E for ; Mon, 21 Oct 2019 13:59:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="dz1Wrc9h" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 510B32166E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-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=bombadil.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Message-ID:References:In-Reply-To:From:Date: MIME-Version:Subject:To:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=X4pqCSQ+8jnPJsl+g9QvP253UolS4luQTNMvenoNuU0=; b=dz1Wrc9hkN+32YMKeMFHK0dcw mPd0b95kDBtw0NOBnUlEzYY2AD8Ws0of95BSfMp+BZ9IbGYYIWI9mD1VdkAKYKZsTWWM8/tzXsvfs 5pli7GguxFlP1Rsp4RBSX/+RwHzHhvD+p4TKB9AFVtPaBFHocPzv5Yx8Bt5e1irU+trmbtvRAC/NH QHAZyDbjN/JkKOjEc81swy6iBSikf6UM1X8ROinKJr8gKznI7Jg7waA1SPNzTCatuKwE8NYfqIdng jfEpmW/7xddRJx5gZlaj/y6+sd9HKBmnDki3Lglssm9ZxbkZVB3JpXzmuskRUg5DHuxq16buGPHeV 5rTmTPkYw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iMYDi-0000dQ-WF; Mon, 21 Oct 2019 13:59:39 +0000 Received: from inca-roads.misterjones.org ([213.251.177.50]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iMYDb-0000aJ-1d for linux-arm-kernel@lists.infradead.org; Mon, 21 Oct 2019 13:59:33 +0000 Received: from www-data by cheepnis.misterjones.org with local (Exim 4.80) (envelope-from ) id 1iMYDV-0004zv-5h; Mon, 21 Oct 2019 15:59:25 +0200 To: Christoffer Dall Subject: Re: [PATCH v3 0/2] Improve handling of stage 2 aborts without instruction decode X-PHP-Originating-Script: 0:main.inc MIME-Version: 1.0 Date: Mon, 21 Oct 2019 14:59:24 +0100 From: Marc Zyngier In-Reply-To: <20191021133707.GA2652@e113682-lin.lund.arm.com> References: <20191011110709.2764-1-christoffer.dall@arm.com> <865zkjzpbf.wl-maz@kernel.org> <20191021133707.GA2652@e113682-lin.lund.arm.com> Message-ID: <3ba9db99efaadd8c9372708358da0ac6@www.loen.fr> X-Sender: maz@kernel.org User-Agent: Roundcube Webmail/0.7.2 X-SA-Exim-Connect-IP: X-SA-Exim-Rcpt-To: christoffer.dall@arm.com, kvmarm@lists.cs.columbia.edu, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, linux-arm-kernel@lists.infradead.org, graf@amazon.com, berrange@redhat.com, xypron.glpk@gmx.de, stefanha@redhat.com, peter.maydell@linaro.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on cheepnis.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191021_065931_241735_FDD8D95E X-CRM114-Status: GOOD ( 17.96 ) 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 , =?UTF-8?Q?=22Daniel_P=2E_Berrang=C3=A9=22?= , Suzuki K Poulose , Heinrich Schuchardt , Alexander Graf , Julien Thierry , Stefan Hajnoczi , James Morse , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2019-10-21 14:37, Christoffer Dall wrote: > On Sun, Oct 20, 2019 at 11:25:24AM +0100, Marc Zyngier wrote: >> Hi Christoffer, >> >> On Fri, 11 Oct 2019 12:07:04 +0100, >> Christoffer Dall wrote: >> > >> > When a guest accesses memory outside the memory slots, KVM usually >> > bounces the access back to userspace with KVM_EXIT_MMIO. However, >> on >> > arm/arm64 systems, certain load/store instructions did not provide >> > decoding info for the hypervisor to emulate the instruction, and >> in this >> > case KVM has rather rudely returned -ENOSYS and printed a not >> overly >> > helpful error message: >> > >> > load/store instruction decoding not implemented >> > >> > This patch series improves the error message and allows userspace >> to be >> > notified of this event instead of receiving -ENOSYS, and also >> allows >> > userspace to ask KVM to inject an external abort to the guest, >> which it >> > can use for any memory access that it either cannot handle. >> > >> > One remaining case which this patch set does not address is if the >> guest >> > accesses an in-kernel emulated device, such as the VGIC, but using >> a >> > load/store instruction which doesn't provide decode info. With >> these >> > patches, this will return to userspace for it to handle, but >> there's no >> > way for userspace to return the decoding information to KVM and >> have KVM >> > complete the access to the in-kernel emulated device. I have no >> plans >> > to address this limitation. >> >> You had some pending comments on patch 2, and you seem to indicate >> that you would respin the series. Do you have plans to do so in the >> coming days? I'd like to put that series into -next, but I can >> either >> wait for your respin, or queue it as it is and apply fixes on top. >> > > I think those for v2 and this is v3 which should address those > concerns. > Did I miss something or manage to confuse mysel here? Gah! No, it looks like the mistake is mine. I've mixed the two series in my Inbox, and the result is a total brain-fart. Ignore me. I'll queue these patches ASAP. Thanks, M. -- Jazz is not dead. It just smells funny... _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel