From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f74.google.com (mail-ed1-f74.google.com [209.85.208.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 895BE31F9BE for ; Fri, 19 Jun 2026 07:07:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781852844; cv=none; b=aTTXKviKqPWWPooR2u0eE1mxvXDJotyuW2yEWRkXg1wr3i6ARDvPPUm6t9i0XNTybSAS+9XFaJfYdkHY4T/k9Fpg2rKGB8gzy8TzBlQBzUnIZjqlzV7MMkMNlOyOoB9otrlHfKAlt5G+wtc7x1+fCOKQ4XCH0SwS3RN25fV7B7o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781852844; c=relaxed/simple; bh=vmVLbKC5hr2bvTnRY+33FRlAabR9MaR638SdlHcGoNM=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=AvZrlKeiJYcdSJEZy82YbuCyToT0SvIcvSz+fR77UwBa92s/JGk1UApq68juwWoAIU5ydA5S1/otOlQOxnz80tJ4NANcpVAsrhiAKlqoIGWhldOcHNpRs3vxMn3RmnbYoNfq83SkJtvsgNgasXTtOiBPBL0AY8c7U3dd3bIeDTw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--tabba.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=ETeku6lC; arc=none smtp.client-ip=209.85.208.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--tabba.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ETeku6lC" Received: by mail-ed1-f74.google.com with SMTP id 4fb4d7f45d1cf-697560b83f4so374931a12.1 for ; Fri, 19 Jun 2026 00:07:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1781852841; x=1782457641; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=PGcRBYs3Z9Uumpf23hDhMQDIQ6d9ZOsDwaNEYfVocws=; b=ETeku6lCTohTZqE/Mt4wJxRgN6HN3X5BqQQBmc06Y1yQ+YYHgNTpYkQLDpO/q5tMua 0ry252aKR3gNiKBj5aM+LnyDc7BWRhRA+4NbJLPPBcpZwt1FMvzCq4vYfXQfu8LytiLo i/ugICu0VwBzrImPydeia7HZV8w5QwJms7LjLLzGYvtSoxqBPpKacGhsSh8sZGxNYU33 UxrvDdUelBaxSceMAGGDztCQmGLiVAl21djYcguzzJWISHgaqEpPoS5v/0q2UYct4J9l 12Q1zUJjxitcT0/SsczjpdeSVgMvwHwSqVoTOBncZgwvuMxQmoJ9K+YHsCV5KwNvyQGU rH6A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781852841; x=1782457641; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=PGcRBYs3Z9Uumpf23hDhMQDIQ6d9ZOsDwaNEYfVocws=; b=b4UHzRYQXQpf5WOZaH0I2RbsFmxGz412d5ftvINa1Ysd652mWhOFbX+jIJ8YijPwYm LDP+1AkmcAgzCmiVKA8/UMw2X8G8jXlHsILvMPgkLR/uSr1OlLPWaVsFi9SEWPKgp74W De2g3A3Py6GA9TGVTrSF0Qro6w57kWcua1Dm0FCw16NLV/O+UZPK0v8i9NV2Gtoi6j/O 4TTAhOhd++eR3lSacJtzlzWJnpkZHJUirPEVFoHFRsd7yxSXHGmb0+OlQ8qQAJUcmiVe GtpxidEApmJ/JDEoFS9qaZQyLtlzO55u4MH2fgwci1BXYqoq9g9VTAMyuNIaHPycaIMN uicA== X-Forwarded-Encrypted: i=1; AFNElJ8nK4VmaguUpse9dsMOcrwoxW4Ei4hJUT2XmlFYYfMQdXjq+PnCuHs9fdPqYHdNFdTLbecNK1a7VkP+Wuw=@vger.kernel.org X-Gm-Message-State: AOJu0Yy+YnDEqfwtZnB9QztqMDghe+97lA8UU7dCxRqZp6W0TEioPkMb 7HINk337HDXaIpd84yVe3iCxoE3novmpFfNhb9BzAEgSZHS/gYPjSqhhrDK+I8D8RorL+yZ7uGh 5eQ== X-Received: from edf28.prod.google.com ([2002:a05:6402:21dc:b0:692:3d87:5b0d]) (user=tabba job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6402:5288:b0:68b:ca3c:6bbb with SMTP id 4fb4d7f45d1cf-6973bcaa247mr932499a12.11.1781852840465; Fri, 19 Jun 2026 00:07:20 -0700 (PDT) Date: Fri, 19 Jun 2026 08:07:11 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.55.0.rc0.738.g0c8ab3ebcc-goog Message-ID: <20260619070719.812227-1-tabba@google.com> Subject: [PATCH v2 0/8] KVM: arm64: Rework pKVM vCPU state synchronisation From: Fuad Tabba To: Marc Zyngier , Oliver Upton , kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Catalin Marinas , Will Deacon , Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , Vincent Donnefort , Quentin Perret , Sebastian Ene , Hyunwoo Kim , Fuad Tabba Content-Type: text/plain; charset="UTF-8" Hi folks, Changes since v1 [2]: - Dropped the guard()/scoped_guard() conversion patches: standalone churn on code this series does not otherwise rework. (Marc) - Rebased onto kvmarm/next. The VGIC flush primitive now bounds used_lrs using the cached hyp_gicv3_nr_lr instead of reading ICH_VTR_EL2 on every entry. (Marc) - Grouped the PKVM_HOST_STATE_DIRTY flag with the other iflags and clarified its comment. (Marc) - Sync PSTATE alongside PC on every non-protected exit, and sync+dirty before host-side SError injection so the syndrome is not dropped. (sashiko) - Various cleanups and tidying up. (Vincent) Building on Will's pKVM infrastructure series [1], this series reworks how pKVM moves vCPU state between the host and EL2, and stops copying a non-protected guest's state on every world switch. EL2 gains proper primitives for the state it transfers: vCPU lookup helpers, and VGIC flush/sync that reduces how much host state EL2 dereferences. The series also moves some preparatory code (such as sys reg access and PSCI helpers) to shared headers and HYP, and implements lazy copying of a non-protected guest's register state back to the host until the host actually needs it, instead of on every exit. This is the first of two series moving pKVM vCPU state management to EL2. The follow-up completes the job for protected VMs: state isolation, PSCI handling at EL2, and the resulting API behaviour. The series is structured as follows: 01-04: Preparatory refactoring (MPIDR, sys reg access, vCPU reset, PSCI helpers) to shared headers and HYP. 05: Host and hypervisor vCPU lookup primitives. 06-07: VGIC: reduce EL2's exposure to host state, add flush/sync primitives. 08: Lazy state sync for non-protected guests. Based on kvmarm/next. [1] https://lore.kernel.org/all/20260105154939.11041-1-will@kernel.org/ [2] https://lore.kernel.org/all/20260612065925.755562-1-tabba@google.com/ Cheers, /fuad Fuad Tabba (5): KVM: arm64: Extract MPIDR computation into a shared header KVM: arm64: Make vcpu_{read,write}_sys_reg available to HYP code KVM: arm64: Factor out reusable vCPU reset helpers KVM: arm64: Move PSCI helper functions to a shared header KVM: arm64: Implement lazy vCPU state sync for non-protected guests Marc Zyngier (3): KVM: arm64: Add host and hypervisor vCPU lookup primitives KVM: arm64: Minimise EL2's exposure of host VGIC state during world switch KVM: arm64: Add primitives to flush/sync the VGIC state at EL2 arch/arm64/include/asm/kvm_arm.h | 12 ++ arch/arm64/include/asm/kvm_asm.h | 1 + arch/arm64/include/asm/kvm_emulate.h | 79 +++++++- arch/arm64/include/asm/kvm_host.h | 2 + arch/arm64/kvm/arm.c | 7 + arch/arm64/kvm/handle_exit.c | 30 ++++ arch/arm64/kvm/hyp/exception.c | 34 +--- arch/arm64/kvm/hyp/nvhe/hyp-main.c | 258 +++++++++++++++++++++++---- arch/arm64/kvm/psci.c | 30 +--- arch/arm64/kvm/reset.c | 60 +------ arch/arm64/kvm/sys_regs.c | 14 +- arch/arm64/kvm/sys_regs.h | 19 ++ include/kvm/arm_psci.h | 27 +++ 13 files changed, 410 insertions(+), 163 deletions(-) -- 2.55.0.rc0.738.g0c8ab3ebcc-goog