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=-5.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 5C17AC433DB for ; Tue, 29 Dec 2020 17:04:44 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id C920A20867 for ; Tue, 29 Dec 2020 17:04:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C920A20867 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=armlinux.org.uk 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 0C5674B295; Tue, 29 Dec 2020 12:04:43 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@armlinux.org.uk 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 BhNQE-R5ERvM; Tue, 29 Dec 2020 12:04:41 -0500 (EST) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id ECB5C4B249; Tue, 29 Dec 2020 12:04:41 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 8A8934B255 for ; Tue, 29 Dec 2020 12:04:40 -0500 (EST) 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 jLIg01xBsFlz for ; Tue, 29 Dec 2020 12:04:39 -0500 (EST) Received: from pandora.armlinux.org.uk (unknown [78.32.30.218]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 006D64B249 for ; Tue, 29 Dec 2020 12:04:38 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=FhCXE7slKDeIxopRDJZcSEDk1dcwjpLiihzO8A1DLYI=; b=AYhIRsKhcTRQMcw8YcP2xAlQP ZJ7L1gjPikShRcrMBIm+phM9DzBwgyb0v11vAj4qepLHcuoQCQ/NlJtACcoE85OrXpInyCAaBMdSK Td2Oykho2vQPWR407CJe6NN7DvuTOvf4sZVp/IqpijQq4Ql19Eth2DJJNXKEADW40L9qBSdzqth9B EFsTsXoylISXM1eFdZlh/4udhreDKyRgx2I56jZQ5P2Y9KY1s7hN0PXwTmxKSY1hBY9a8Zin52g22 EXWzcXymEZ+3X3p4nwONwEJSJrHE8RtZQ5JTPQcg5BmKCwqOrdP16VOMLuXW4iPmd675vwWZ8D84Y UNTNCYeMQ==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:44878) by pandora.armlinux.org.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1kuIPv-0005F2-Sw; Tue, 29 Dec 2020 17:04:16 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.92) (envelope-from ) id 1kuIPs-0001ON-Dm; Tue, 29 Dec 2020 17:04:12 +0000 Date: Tue, 29 Dec 2020 17:04:12 +0000 From: Russell King - ARM Linux admin To: David Brazdil Subject: Re: [PATCH] KVM: arm64: Allow PSCI SYSTEM_OFF/RESET to return Message-ID: <20201229170412.GN1551@shell.armlinux.org.uk> References: <20201229160059.64135-1-dbrazdil@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201229160059.64135-1-dbrazdil@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Cc: Lorenzo Pieralisi , Catalin Marinas , Will Deacon , Marc Zyngier , linux-kernel@vger.kernel.org, Sudeep Holla , kernel-team@android.com, 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 Tue, Dec 29, 2020 at 04:00:59PM +0000, David Brazdil wrote: > The KVM/arm64 PSCI relay assumes that SYSTEM_OFF and SYSTEM_RESET should > not return, as dictated by the PSCI spec. However, there is firmware out > there which breaks this assumption, leading to a hyp panic. Make KVM > more robust to broken firmware by allowing these to return. Are you sure you should just return? We've had issues in the past with Linux reboot(2) that returns to userspace, allowing on 32-bit ARM for example watchdogs to unexpectedly continue being serviced. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last! _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm