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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 40604CA9EAF for ; Mon, 21 Oct 2019 13:37:33 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id B78B420873 for ; Mon, 21 Oct 2019 13:37:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B78B420873 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com 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 260C24A9D5; Mon, 21 Oct 2019 09:37:32 -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 WBne+aNJLA1F; Mon, 21 Oct 2019 09:37:31 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 0F3F14A991; Mon, 21 Oct 2019 09:37:31 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 891654A96B for ; Mon, 21 Oct 2019 09:37:30 -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 2Fc+uVBqmTCo for ; Mon, 21 Oct 2019 09:37:29 -0400 (EDT) Received: from foss.arm.com (unknown [217.140.110.172]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 67E8A4A73A for ; Mon, 21 Oct 2019 09:37:29 -0400 (EDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 013AB493; Mon, 21 Oct 2019 06:37:09 -0700 (PDT) Received: from localhost (e113682-lin.copenhagen.arm.com [10.32.145.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 87DD13F718; Mon, 21 Oct 2019 06:37:08 -0700 (PDT) Date: Mon, 21 Oct 2019 15:37:07 +0200 From: Christoffer Dall To: Marc Zyngier Subject: Re: [PATCH v3 0/2] Improve handling of stage 2 aborts without instruction decode Message-ID: <20191021133707.GA2652@e113682-lin.lund.arm.com> References: <20191011110709.2764-1-christoffer.dall@arm.com> <865zkjzpbf.wl-maz@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <865zkjzpbf.wl-maz@kernel.org> User-Agent: Mutt/1.10.1 (2018-07-13) Cc: =?utf-8?B?IkRhbmllbCBQLiBCZXJyYW5nw6ki?= , 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-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu 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? Thanks, Christoffer _______________________________________________ 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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 30C4BCA9EB7 for ; Mon, 21 Oct 2019 13:37:34 +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 0345A20873 for ; Mon, 21 Oct 2019 13:37:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="JwZ/9HQg" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0345A20873 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com 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-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=v5KnZh7Em00BXzGFUOQbukmJOs7LG0L0EJuwocHlsaw=; b=JwZ/9HQg+CzOZl TEkkwAwO+eZosJaFwxJDl/Ln38NtMqc726Led1Fmt3WGLIfy8ST69EhuCILFVgELUfR9wytjXZk5Q zejkhVloA2eAMko3SSrgCnn6zb4A0HOW7JofBH4GWXp68+CR46WdO/zMRGhOXDs/bDBh9E1YOG0AC 4SRxe1KiTSpW/0eTN5dytDmH07hE8mzWdDPE5xcsl8/Husxc2MEFxRXBv5ZEPcA9gQdYzmKXKamPT nyQeBNWxQu9vW92vPhwou1lZ+BW9ZTes4mAtbqmtfX0IX5b2Ibc+kgD3efXyB5l5txOq79QrtwRlI dJrkeQ63yBHm2PLpu6/g==; 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 1iMXsD-0005eL-NM; Mon, 21 Oct 2019 13:37:25 +0000 Received: from [217.140.110.172] (helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iMXsA-0005cG-69 for linux-arm-kernel@lists.infradead.org; Mon, 21 Oct 2019 13:37:23 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 013AB493; Mon, 21 Oct 2019 06:37:09 -0700 (PDT) Received: from localhost (e113682-lin.copenhagen.arm.com [10.32.145.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 87DD13F718; Mon, 21 Oct 2019 06:37:08 -0700 (PDT) Date: Mon, 21 Oct 2019 15:37:07 +0200 From: Christoffer Dall To: Marc Zyngier Subject: Re: [PATCH v3 0/2] Improve handling of stage 2 aborts without instruction decode Message-ID: <20191021133707.GA2652@e113682-lin.lund.arm.com> References: <20191011110709.2764-1-christoffer.dall@arm.com> <865zkjzpbf.wl-maz@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <865zkjzpbf.wl-maz@kernel.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191021_063722_270711_30DC05FE X-CRM114-Status: GOOD ( 20.69 ) 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?B?IkRhbmllbCBQLiBCZXJyYW5nw6ki?= , 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-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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? Thanks, Christoffer _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel