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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 DEF6BC43381 for ; Wed, 17 Mar 2021 14:40:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A06C864F26 for ; Wed, 17 Mar 2021 14:40:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231952AbhCQOk1 (ORCPT ); Wed, 17 Mar 2021 10:40:27 -0400 Received: from foss.arm.com ([217.140.110.172]:34576 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232228AbhCQOkN (ORCPT ); Wed, 17 Mar 2021 10:40:13 -0400 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 AE30EED1; Wed, 17 Mar 2021 07:40:09 -0700 (PDT) Received: from e121166-lin.cambridge.arm.com (e121166-lin.cambridge.arm.com [10.1.196.255]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 08F8F3F792; Wed, 17 Mar 2021 07:40:08 -0700 (PDT) Date: Wed, 17 Mar 2021 14:40:04 +0000 From: Lorenzo Pieralisi To: Marc Zyngier Cc: linux-kernel@vger.kernel.org, LAKML , KVM Subject: Re: [PATCH v3 1/1] irqchip/gic-v4.1: Disable vSGI upon (GIC CPUIF < v4.1) detection Message-ID: <20210317144004.GA6593@e121166-lin.cambridge.arm.com> References: <20210302102744.12692-1-lorenzo.pieralisi@arm.com> <20210317100719.3331-1-lorenzo.pieralisi@arm.com> <20210317100719.3331-2-lorenzo.pieralisi@arm.com> <87blbhj2q3.wl-maz@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87blbhj2q3.wl-maz@kernel.org> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 17, 2021 at 02:04:36PM +0000, Marc Zyngier wrote: > Hi Lorenzo, > > Wed, 17 Mar 2021 10:07:19 +0000, > Lorenzo Pieralisi wrote: > > > > GIC CPU interfaces versions predating GIC v4.1 were not built to > > accommodate vINTID within the vSGI range; as reported in the GIC > > specifications (8.2 "Changes to the CPU interface"), it is > > CONSTRAINED UNPREDICTABLE to deliver a vSGI to a PE with > > ID_AA64PFR0_EL1.GIC < b0011. > > > > Check the GIC CPUIF version by reading the SYS_ID_AA64_PFR0_EL1. > > > > Disable vSGIs if a CPUIF version < 4.1 is detected to prevent using > > vSGIs on systems where they may misbehave. > > > > Signed-off-by: Lorenzo Pieralisi > > Cc: Marc Zyngier > > Does it need to go in as a fix? or can it just be pushed into 5.13? > Given that there is no such HW in the wild just yet, I'm inclined to > do the latter... I agree with you; it is to make the driver/vgic robust against HW misconfigurations (because that's what they are and I am not aware of any _existing_ HW with such a misconfiguration - yet), 5.13 will perfectly do. Thanks a lot. Lorenzo 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=-10.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 51076C433E0 for ; Wed, 17 Mar 2021 14:47:16 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 53D6764E21 for ; Wed, 17 Mar 2021 14:47:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 53D6764E21 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com 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=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:Cc: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=FCts8i/Q/qncmy4CPmbt0WehDSrXhM+s+X1SpdUeFj0=; b=OQ6ekSc+hIKSh3OLC3nxV1M+B oz3mBydFdi1eyXldT5W58i1QQmcJMdbJvPzG5Gk22f9/JCuk29F5v5hZV0rct8L/+gyBLOJorN1dV 3F8QPQQjlGyJBs1lLZaX4Dxx/cyCpFXkVnbH+tqjdhkKuLqOwll8GflHssPolLy1FRMj3J5e437bz ue8few9bqVqWkXTh0jrRmkmOWXtQOZQXDwp2GsMu31KhX26/SqgXFWl5BuNaV/eK+MrDWJr/SCXCj 12GpvHQdARcp4ko+EQ2rvEuugtDfJSNF70t3cEvOe8MOQsHO8YSEHWCjlHcHI5fTZX/HBG/f9hg50 0gkT+Tw1g==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lMXQH-003KoM-F8; Wed, 17 Mar 2021 14:45:21 +0000 Received: from foss.arm.com ([217.140.110.172]) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lMXLH-003ILB-Jp for linux-arm-kernel@lists.infradead.org; Wed, 17 Mar 2021 14:40:13 +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 AE30EED1; Wed, 17 Mar 2021 07:40:09 -0700 (PDT) Received: from e121166-lin.cambridge.arm.com (e121166-lin.cambridge.arm.com [10.1.196.255]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 08F8F3F792; Wed, 17 Mar 2021 07:40:08 -0700 (PDT) Date: Wed, 17 Mar 2021 14:40:04 +0000 From: Lorenzo Pieralisi To: Marc Zyngier Cc: linux-kernel@vger.kernel.org, LAKML , KVM Subject: Re: [PATCH v3 1/1] irqchip/gic-v4.1: Disable vSGI upon (GIC CPUIF < v4.1) detection Message-ID: <20210317144004.GA6593@e121166-lin.cambridge.arm.com> References: <20210302102744.12692-1-lorenzo.pieralisi@arm.com> <20210317100719.3331-1-lorenzo.pieralisi@arm.com> <20210317100719.3331-2-lorenzo.pieralisi@arm.com> <87blbhj2q3.wl-maz@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <87blbhj2q3.wl-maz@kernel.org> User-Agent: Mutt/1.9.4 (2018-02-28) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210317_144011_847965_0254D2B7 X-CRM114-Status: GOOD ( 16.34 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 Wed, Mar 17, 2021 at 02:04:36PM +0000, Marc Zyngier wrote: > Hi Lorenzo, > > Wed, 17 Mar 2021 10:07:19 +0000, > Lorenzo Pieralisi wrote: > > > > GIC CPU interfaces versions predating GIC v4.1 were not built to > > accommodate vINTID within the vSGI range; as reported in the GIC > > specifications (8.2 "Changes to the CPU interface"), it is > > CONSTRAINED UNPREDICTABLE to deliver a vSGI to a PE with > > ID_AA64PFR0_EL1.GIC < b0011. > > > > Check the GIC CPUIF version by reading the SYS_ID_AA64_PFR0_EL1. > > > > Disable vSGIs if a CPUIF version < 4.1 is detected to prevent using > > vSGIs on systems where they may misbehave. > > > > Signed-off-by: Lorenzo Pieralisi > > Cc: Marc Zyngier > > Does it need to go in as a fix? or can it just be pushed into 5.13? > Given that there is no such HW in the wild just yet, I'm inclined to > do the latter... I agree with you; it is to make the driver/vgic robust against HW misconfigurations (because that's what they are and I am not aware of any _existing_ HW with such a misconfiguration - yet), 5.13 will perfectly do. Thanks a lot. Lorenzo _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel