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=-17.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 E3D92C433C1 for ; Tue, 23 Mar 2021 16:25:08 +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 650646198C for ; Tue, 23 Mar 2021 16:25:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 650646198C 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+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:MIME-Version:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=r4dSuAErusEFmA+kz6g9fAVOKh+cSmrVtckE9WE7w/g=; b=AhwI3VIUj9T+0a1jKMepRooFFU +nFr3p2wfgEg+iVAXRBNQ5ER7ytwoOpOCga3dv2Lx3XcMgGbNPDgfEcw+QUFWKcivDFZKpFuRMzuB p18YqA3YJc+sdo1JehLLjkYUaCaXpWi31IZueGzR8wtnVy4x9TgkYcIPmo/MEaJqxWvdaGkWAyFss 6xq+Oofulh/3FR/SVe3KLSZGvTUZJpqw7cQKR4M4oGu4PJbAHfQ7fmwKAfPRlDMZRFiQz6W4fOuDg YkOhr2QNToAdCys8f7BwwplGhHG2piJazGthigdb35XIg5CTDbtSJi5S8UpRYtCHyuV8OswMNOfKH LwoL7iPA==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lOjoM-00FJCm-Nf; Tue, 23 Mar 2021 16:23:18 +0000 Received: from mail.kernel.org ([198.145.29.99]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lOjoH-00FJAt-Ri for linux-arm-kernel@lists.infradead.org; Tue, 23 Mar 2021 16:23:16 +0000 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4B937619B8; Tue, 23 Mar 2021 16:23:08 +0000 (UTC) Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=hot-poop.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1lOjoA-003LOd-7E; Tue, 23 Mar 2021 16:23:06 +0000 From: Marc Zyngier To: kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Ard Biesheuvel , kernel-team@android.com, Shameerali Kolothum Thodi Subject: [PATCH] KVM: arm64: Fix CPU interface MMIO compatibility detection Date: Tue, 23 Mar 2021 16:23:01 +0000 Message-Id: <20210323162301.2049595-1-maz@kernel.org> X-Mailer: git-send-email 2.30.0 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, ardb@kernel.org, kernel-team@android.com, shameerali.kolothum.thodi@huawei.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210323_162314_198497_C0885E96 X-CRM114-Status: GOOD ( 12.39 ) 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 In order to detect whether a GICv3 CPU interface is MMIO capable, we switch ICC_SRE_EL1.SRE to 0 and check whether it sticks. However, this is only possible if *ALL* of the HCR_EL2 interrupt overrides are set, and the CPU is perfectly allowed to ignore the write to ICC_SRE_EL1 otherwise. This leads KVM to pretend that a whole bunch of ARMv8.0 CPUs aren't MMIO-capable, and breaks VMs that should work correctly otherwise. Fix this by setting IMO/FMO/IMO before touching ICC_SRE_EL1, and clear them afterwards. This allows us to reliably detect the CPU interface capabilities. Cc: Shameerali Kolothum Thodi Fixes: 9739f6ef053f ("KVM: arm64: Workaround firmware wrongly advertising GICv2-on-v3 compatibility") Signed-off-by: Marc Zyngier --- arch/arm64/kvm/hyp/vgic-v3-sr.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm64/kvm/hyp/vgic-v3-sr.c b/arch/arm64/kvm/hyp/vgic-v3-sr.c index ee3682b9873c..39f8f7f9227c 100644 --- a/arch/arm64/kvm/hyp/vgic-v3-sr.c +++ b/arch/arm64/kvm/hyp/vgic-v3-sr.c @@ -429,6 +429,13 @@ u64 __vgic_v3_get_gic_config(void) if (has_vhe()) flags = local_daif_save(); + /* + * Table 11-2 "Permitted ICC_SRE_ELx.SRE settings" indicates + * that to be able to set ICC_SRE_EL1.SRE to 0, all the + * interrupt overrides must be set. You've got to love this. + */ + sysreg_clear_set(hcr_el2, 0, HCR_AMO | HCR_FMO | HCR_IMO); + isb(); write_gicreg(0, ICC_SRE_EL1); isb(); @@ -436,6 +443,8 @@ u64 __vgic_v3_get_gic_config(void) write_gicreg(sre, ICC_SRE_EL1); isb(); + sysreg_clear_set(hcr_el2, HCR_AMO | HCR_FMO | HCR_IMO, 0); + isb(); if (has_vhe()) local_daif_restore(flags); -- 2.30.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel