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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 77517E63CA2 for ; Sun, 25 Jan 2026 15:05:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; 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=QOGflj2luqd5NQJtJjZbnVorjPpwl5Ve2zVEN5dJIyY=; b=bHXaRxP8zhOCLe MMpa2n6L0MdBmfA/nSUoCnw+elwIh7F7Z+q0Ja2Uu8rhFJDIBzfe9yRS4uXa+bMbaVLy2iecoL5+r CRatSTqAx/WMQrskfMRaAphpLUH+wEW/0kzPUIrIXzsWraR28DBkWDlG8mSvG+z9OcGfrq4KIx/n2 HkLwe9MJwYj2yJqyrntS9T5SQzAFxi/KwlG6DZa44MiZP2AvsEy4lMMU4GTNT3mWiSQt7NECzPLIF qDg6RqxQLcsWBzgBXIq6HbXDuXgnZJyctSdYwwTXFGnZpqk6ze2tB4/EuojqqkeK2Oqh2iker5A/O 64g+mOgDqewnT8a9HIVg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vk1gC-0000000BG4G-0SRr; Sun, 25 Jan 2026 15:05:32 +0000 Received: from out30-124.freemail.mail.aliyun.com ([115.124.30.124]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vk1g6-0000000BG2O-00nj; Sun, 25 Jan 2026 15:05:29 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1769353511; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=PMCCCq1cM6dVorAxjoEzFrWStzc4ERTOWpMKDxiriBk=; b=TuA3YYOXauM15LsRJcD9utNPgj3PvfHtY7Eu3xPir7EihsiH4//24cQe1O/it3Vn+VHiRvwGLwXRVPZUxhd96uDbxIZrxGAUz0Cbjf7eG4gvfc6o4QJ0w8bqoKv9xDimQTaOLDelBh5jg4OfjPjgGf34VYm8c5c9tfVRrxvdMbE= Received: from localhost.localdomain(mailfrom:fangyu.yu@linux.alibaba.com fp:SMTPD_---0WxlpgTJ_1769353503 cluster:ay36) by smtp.aliyun-inc.com; Sun, 25 Jan 2026 23:05:06 +0800 From: fangyu.yu@linux.alibaba.com To: pbonzini@redhat.com, corbet@lwn.net, anup@brainfault.org, atish.patra@linux.dev, pjw@kernel.org, palmer@dabbelt.com, aou@eecs.berkeley.edu, alex@ghiti.fr, radim.krcmar@oss.qualcomm.com, andrew.jones@oss.qualcomm.com Cc: guoren@kernel.org, ajones@ventanamicro.com, kvm-riscv@lists.infradead.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Fangyu Yu Subject: [PATCH v3 0/2] Support runtime configuration for per-VM's HGATP mode Date: Sun, 25 Jan 2026 23:04:48 +0800 Message-Id: <20260125150450.27068-1-fangyu.yu@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 (Apple Git-146) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260125_070527_635138_6DD72E5B X-CRM114-Status: UNSURE ( 6.68 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@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-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Fangyu Yu Currently, RISC-V KVM hardcodes the G-stage page table format (HGATP mode) to the maximum mode detected at boot time (e.g., SV57x4 if supported). but often such a wide GPA is unnecessary, just as a host sometimes doesn't need sv57. This patch introduces per-VM configurability of the G-stage mode via a new KVM capability: KVM_CAP_RISCV_SET_HGATP_MODE. User-space can now explicitly request a specific HGATP mode (SV39x4, SV48x4, or SV57x4 on 64-bit) during VM creation. --- Changes in v3: - Reworked the patch formatting (per Drew). - Dropped kvm->arch.kvm_riscv_gstage_mode and derive HGATP.MODE from kvm_riscv_gstage_pgd_levels via a helper, avoiding redundant per-VM state(per Drew). - Removed kvm_riscv_gstage_max_mode and keep only kvm_riscv_gstage_max_pgd_levels for host capability detection(per Drew). - Other initialization and return value issues(per Drew). - Enforce that KVM_CAP_RISCV_SET_HGATP_MODE can only be enabled before any vCPUs are created by rejecting the ioctl once kvm->created_vcpus is non-zero(per Radim). - Add a memslot safety check and reject the capability unless kvm_are_all_memslots_empty(kvm) is true, ensuring the G-stage format is not changed after any memslots have been installed(per Radim). - Link to v2: https://lore.kernel.org/linux-riscv/20260105143232.76715-1-fangyu.yu@linux.alibaba.com/ --- Fangyu Yu (2): RISC-V: KVM: Support runtime configuration for per-VM's HGATP mode RISC-V: KVM: add KVM_CAP_RISCV_SET_HGATP_MODE Documentation/virt/kvm/api.rst | 18 +++++++ arch/riscv/include/asm/kvm_gstage.h | 11 ++--- arch/riscv/include/asm/kvm_host.h | 19 +++++++ arch/riscv/kvm/gstage.c | 77 ++++++++++++++++------------- arch/riscv/kvm/main.c | 12 ++--- arch/riscv/kvm/mmu.c | 23 ++++++--- arch/riscv/kvm/vm.c | 28 +++++++++-- arch/riscv/kvm/vmid.c | 3 +- include/uapi/linux/kvm.h | 1 + 9 files changed, 133 insertions(+), 59 deletions(-) -- 2.50.1 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv