From nobody Mon Apr 6 00:43:23 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6ACF8C678D6 for ; Mon, 16 Jan 2023 04:05:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231836AbjAPEFw (ORCPT ); Sun, 15 Jan 2023 23:05:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231831AbjAPEFj (ORCPT ); Sun, 15 Jan 2023 23:05:39 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 548F672B0 for ; Sun, 15 Jan 2023 20:04:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673841890; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=QaWOUNPCOLrCK48ZZkRvvzXiWltPmrtQJNoTHypPAnc=; b=HKDbWkaDlwvANzXdGDMBuAvQQLQ5wZgG+kfzUKN96ItVWuO08B1eTLHdqFAUx13ulTRGvK 4LOKJxSep5X2Nv+N/e6NPSJoLlwkOjqD64tpL8uxWLDhU9mAjVLoY5Oh/UyJYc6cxN2Pbk MFUrAZbHzwSrdqSCn5TRMAydDtxLIrA= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-556-v6iwQVNQNJqo5UeIelcYkA-1; Sun, 15 Jan 2023 23:04:45 -0500 X-MC-Unique: v6iwQVNQNJqo5UeIelcYkA-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 3F8691C08DA2; Mon, 16 Jan 2023 04:04:44 +0000 (UTC) Received: from gshan.redhat.com (vpn2-54-98.bne.redhat.com [10.64.54.98]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 44027492B05; Mon, 16 Jan 2023 04:04:36 +0000 (UTC) From: Gavin Shan To: kvmarm@lists.linux.dev Cc: kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com, maz@kernel.org, corbet@lwn.net, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, ricarkol@google.com, eric.auger@redhat.com, yuzhe@nfschina.com, renzhengeek@gmail.com, ardb@kernel.org, peterx@redhat.com, seanjc@google.com, shan.gavin@gmail.com Subject: [PATCH 1/4] KVM: arm64: Allow saving vgic3 LPI pending status in no running vcpu context Date: Mon, 16 Jan 2023 12:04:02 +0800 Message-Id: <20230116040405.260935-2-gshan@redhat.com> In-Reply-To: <20230116040405.260935-1-gshan@redhat.com> References: <20230116040405.260935-1-gshan@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" When dirty ring is enabled, the dirty page information is pushed to the dirty ring if there is a running VCPU context. Otherwise, the dirty page information is still tracked by the backup dirty bitmap. In order to detect if there is a running VCPU context when a guest page becomes dirty, kvm_arch_allow_write_without_running_vcpu() was introduced to warn when no running VCPU context exists on unknown cases. Other than the site of saving ITS tables, it's possible to save vgic3 LPI pending status in no running vcpu context because it can happen when ITS ITE is restored through the command KVM_DEV_ARM_ITS_RESTORE_TABLES on 'kvm-arm-vgic-its' device. Fix it by allowing to save vgic3 LPI pending status in no running vcpu context. Signed-off-by: Gavin Shan --- Documentation/virt/kvm/api.rst | 5 +++-- arch/arm64/kvm/vgic/vgic-its.c | 3 ++- arch/arm64/kvm/vgic/vgic-v3.c | 3 +++ include/kvm/arm_vgic.h | 1 + 4 files changed, 9 insertions(+), 3 deletions(-) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 9807b05a1b57..18b245a0ba02 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -8071,8 +8071,9 @@ state is final and avoid missing dirty pages from ano= ther ioctl ordered after the bitmap collection. =20 NOTE: One example of using the backup bitmap is saving arm64 vgic/its -tables through KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_SAVE_TABLES} command on -KVM device "kvm-arm-vgic-its" when dirty ring is enabled. +tables and vgic3 LPI pending status through KVM_DEV_ARM_{VGIC_GRP_CTRL, +ITS_SAVE_TABLES} and KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_RESTORE_TABLES} +command on KVM device "kvm-arm-vgic-its" when dirty ring is enabled. =20 8.30 KVM_CAP_XEN_HVM -------------------- diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index 94a666dd1443..119a9c7a0a52 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -2792,7 +2792,8 @@ bool kvm_arch_allow_write_without_running_vcpu(struct= kvm *kvm) { struct vgic_dist *dist =3D &kvm->arch.vgic; =20 - return dist->save_its_tables_in_progress; + return dist->save_vgic_v3_tables_in_progress || + dist->save_its_tables_in_progress; } =20 static int vgic_its_set_attr(struct kvm_device *dev, diff --git a/arch/arm64/kvm/vgic/vgic-v3.c b/arch/arm64/kvm/vgic/vgic-v3.c index 2074521d4a8c..32998c8587a8 100644 --- a/arch/arm64/kvm/vgic/vgic-v3.c +++ b/arch/arm64/kvm/vgic/vgic-v3.c @@ -304,6 +304,7 @@ void vgic_v3_enable(struct kvm_vcpu *vcpu) int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq) { struct kvm_vcpu *vcpu; + struct vgic_dist *dist =3D &kvm->arch.vgic; int byte_offset, bit_nr; gpa_t pendbase, ptr; bool status; @@ -339,7 +340,9 @@ int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, st= ruct vgic_irq *irq) if (status) { /* clear consumed data */ val &=3D ~(1 << bit_nr); + dist->save_vgic_v3_tables_in_progress =3D true; ret =3D kvm_write_guest_lock(kvm, ptr, &val, 1); + dist->save_vgic_v3_tables_in_progress =3D false; if (ret) return ret; } diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 9270cd87da3f..0485b4e82b00 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -264,6 +264,7 @@ struct vgic_dist { =20 bool has_its; bool save_its_tables_in_progress; + bool save_vgic_v3_tables_in_progress; =20 /* * Contains the attributes and gpa of the LPI configuration table. --=20 2.23.0