From patchwork Fri Aug 9 07:48:32 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 11085611 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 76093912 for ; Fri, 9 Aug 2019 07:49:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 68C0B28C4E for ; Fri, 9 Aug 2019 07:49:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5C5DC28C53; Fri, 9 Aug 2019 07:49:08 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 07CD528C49 for ; Fri, 9 Aug 2019 07:49:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405922AbfHIHtH (ORCPT ); Fri, 9 Aug 2019 03:49:07 -0400 Received: from foss.arm.com ([217.140.110.172]:42812 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405811AbfHIHtG (ORCPT ); Fri, 9 Aug 2019 03:49:06 -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 7DDA3344; Fri, 9 Aug 2019 00:49:06 -0700 (PDT) Received: from why.lan (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D509C3F706; Fri, 9 Aug 2019 00:49:04 -0700 (PDT) From: Marc Zyngier To: Paolo Bonzini , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= Cc: Alexandru Elisei , Zenghui Yu , James Morse , Suzuki K Poulose , Julien Thierry , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Subject: [PATCH 4/4] KVM: arm/arm64: vgic: Reevaluate level sensitive interrupts on enable Date: Fri, 9 Aug 2019 08:48:32 +0100 Message-Id: <20190809074832.13283-5-maz@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190809074832.13283-1-maz@kernel.org> References: <20190809074832.13283-1-maz@kernel.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Alexandru Elisei A HW mapped level sensitive interrupt asserted by a device will not be put into the ap_list if it is disabled at the VGIC level. When it is enabled again, it will be inserted into the ap_list and written to a list register on guest entry regardless of the state of the device. We could argue that this can also happen on real hardware, when the command to enable the interrupt reached the GIC before the device had the chance to de-assert the interrupt signal; however, we emulate the distributor and redistributors in software and we can do better than that. Signed-off-by: Alexandru Elisei Signed-off-by: Marc Zyngier --- virt/kvm/arm/vgic/vgic-mmio.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/virt/kvm/arm/vgic/vgic-mmio.c b/virt/kvm/arm/vgic/vgic-mmio.c index 3ba7278fb533..44efc2ff863f 100644 --- a/virt/kvm/arm/vgic/vgic-mmio.c +++ b/virt/kvm/arm/vgic/vgic-mmio.c @@ -113,6 +113,22 @@ void vgic_mmio_write_senable(struct kvm_vcpu *vcpu, struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i); raw_spin_lock_irqsave(&irq->irq_lock, flags); + if (vgic_irq_is_mapped_level(irq)) { + bool was_high = irq->line_level; + + /* + * We need to update the state of the interrupt because + * the guest might have changed the state of the device + * while the interrupt was disabled at the VGIC level. + */ + irq->line_level = vgic_get_phys_line_level(irq); + /* + * Deactivate the physical interrupt so the GIC will let + * us know when it is asserted again. + */ + if (!irq->active && was_high && !irq->line_level) + vgic_irq_set_phys_active(irq, false); + } irq->enabled = true; vgic_queue_irq_unlock(vcpu->kvm, irq, flags);