From patchwork Wed Feb 12 01:43:15 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roman Kisel X-Patchwork-Id: 13970926 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 A90E2C0219B for ; Wed, 12 Feb 2025 01:46:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type: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=ddwZkEyQUKT6tDzGOeyU00Um1SMbmEyI6A+GHcwsesQ=; b=jdutlxjE1gJ6eD0516dYZm3bvh zmf0oRFU+uTI6WLytalQLbYcjrrd2bzY7EXfn8HCdU1XC5+SY3w8YwWq3COZgoHnVxUWJQi3X+2i2 ihzxQ3EX1pLcqm01IjgFvMcTDG/S4VGQhm/dNmdSPrRq3GjjS+zZacBo5aS10fH3bcQYB5ltnsYMH sf8BNsyA8BjiHV764q5wp9x1SXrhfQ2oyMiJFLhOYPpSmEgik1a1pAIYBAWLexKg/2T9beoSWyfNy ivYOSy9/BHl3fkuxFA3vfp0vLso0EFjFD9oB8uOi/N4QAvVzCmYM3rR3uareGBge3etJJIZSVhY1Q Fhq/FGLQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1ti1pT-00000005rrZ-0Hbk; Wed, 12 Feb 2025 01:46:19 +0000 Received: from linux.microsoft.com ([13.77.154.182]) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1ti1mf-00000005r3m-2vZu for linux-arm-kernel@lists.infradead.org; Wed, 12 Feb 2025 01:43:26 +0000 Received: from romank-3650.corp.microsoft.com (unknown [131.107.160.188]) by linux.microsoft.com (Postfix) with ESMTPSA id 161072107AB3; Tue, 11 Feb 2025 17:43:23 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 161072107AB3 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1739324603; bh=ddwZkEyQUKT6tDzGOeyU00Um1SMbmEyI6A+GHcwsesQ=; h=From:To:Cc:Subject:Date:From; b=DLTomIWnXmvy/IgUyCEllQ0h6v7obN9NOU6KTW9W7PW3maU6+JODsXnYDU6UVXFLG nTMW4IaGnwY5732GzMTUMPuZ0cm0L7+xtXlRvGwcImzhI72265Nrsm1ZOCdGqq4nGW nMIJkUmwBYuWSFPcHEII/KpMJzeNA6go5qc7qyrc= From: Roman Kisel To: arnd@arndb.de, bhelgaas@google.com, bp@alien8.de, catalin.marinas@arm.com, conor+dt@kernel.org, dave.hansen@linux.intel.com, decui@microsoft.com, haiyangz@microsoft.com, hpa@zytor.com, krzk+dt@kernel.org, kw@linux.com, kys@microsoft.com, lpieralisi@kernel.org, manivannan.sadhasivam@linaro.org, mingo@redhat.com, robh@kernel.org, ssengar@linux.microsoft.com, tglx@linutronix.de, wei.liu@kernel.org, will@kernel.org, devicetree@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org Cc: benhill@microsoft.com, bperkins@microsoft.com, sunilmut@microsoft.com Subject: [PATCH hyperv-next v4 0/6] arm64: hyperv: Support Virtual Trust Level Boot Date: Tue, 11 Feb 2025 17:43:15 -0800 Message-ID: <20250212014321.1108840-1-romank@linux.microsoft.com> X-Mailer: git-send-email 2.43.0 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250211_174325_780006_95ED2184 X-CRM114-Status: GOOD ( 27.39 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org This patch set allows the Hyper-V code to boot on ARM64 inside a Virtual Trust Level. These levels are a part of the Virtual Secure Mode documented in the Top-Level Functional Specification available at https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/vsm. The OpenHCL paravisor https://github.com/microsoft/openvmm/tree/main/openhcl can serve as a practical application of these patches on ARM64. For validation, I built kernels for the {x86_64, ARM64} x {VTL0, VTL2} set with a small initrd embedded into the kernel and booted VMs managed by Hyper-V and OpenVMM off of that. [V4] - Fixed wording to match acronyms defined in the "Terms and Abbreviations" section of the SMCCC specification throughout the patch series. **Thank you, Michael!** - Replaced the hypervisor ID containing ASCII with an UUID as required by the specification. **Thank you, Michael!** - Added an explicit check for `SMCCC_RET_NOT_SUPPORTED` when discovering the hypervisor presence to make the backward compatibility obvious. **Thank you, Saurabh!** - Split the fix for `get_vtl(void)` out to make it easier to backport. - Refactored the configuration options as requested to eliminate the risk of building non-functional kernels with randomly selected options. **Thank you, Michael!** - Refactored the changes not to introduce an additional file with a one-line function. **Thank you, Wei!** - Fixed change description for the VMBus DeviceTree changes, used `scripts/get_maintainers.pl` on the latest kernel to get the up-to-date list of maintainers as requested. **Thank you, Krzysztof!** - Removed the added (paranoidal+superfluous) checks for DMA coherence in the VMBus driver and instead relied on the DMA and the OF subsystem code. **Thank you, Arnd, Krzysztof, Michael!** - Used another set of APIs for discovering the hardware interrupt number in the VMBus driver to be able to build the driver as a module. **Thank you, Michael, Saurabh!** - Renamed the newly introduced `get_vmbus_root_device(void)` function to `hv_get_vmbus_root_device(void)` as requested. **Thank you, Wei!** - Applied the suggested small-scale refactoring to simplify changes to the Hyper-V PCI driver. Taking the offered liberty of doing the large scale refactoring in another patch series. **Thank you, Michael!** - Added a fix for the issue discovered internally where the CPU would not get the interrupt from a PCI device attached to VTL2 as the shared peripheral interrupt number (SPI) was not offset by 32 (the first valid SPI number). **Thank you, Brian!** [V3] https://lore.kernel.org/lkml/20240726225910.1912537-1-romank@linux.microsoft.com/ - Employed the SMCCC function recently implemented in the Microsoft Hyper-V hypervisor to detect running on Hyper-V/arm64. No dependence on ACPI/DT is needed anymore although the source code still falls back to ACPI as the new hypervisor might be available only in the Windows Insiders channel just yet. - As a part of the above, refactored detecting the hypervisor via ACPI FADT. - There was a suggestion to explore whether it is feasible or not to express that ACPI must be absent for the VTL mode and present for the regular guests in the Hyper-V Kconfig file. My current conclusion is that this will require refactoring in many places. That becomes especially convoluted on x86_64 due to the MSI and APIC dependencies. I'd ask to let us tackle that in another patch series (or chalk up to nice-have's rather than fires to put out) to separate concerns and decrease chances of breakage. - While refactoring `get_vtl(void)` and the related code, fixed the hypercall output address not to overlap with the input as the Hyper-V TLFS mandates: "The input and output parameter lists cannot overlap or cross page boundaries." See https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/hypercall-interface for more. Some might argue that should've been a topic for a separate patch series; I'd counter that the change is well-contained (one line), has no dependencies, and makes the code legal. - Made the VTL boot code (c)leaner as was suggested. - Set DMA cache coherency for the VMBus. - Updated DT bindings in the VMBus documentation (separated out into a new patch). - Fixed `vmbus_set_irq` to use the API that works both for the ACPI and OF. - Reworked setting up the vPCI MSI IRQ domain in the non-ACPI case. The logic looks a bit fiddly/ad-hoc as I couldn't find the API that would fit the bill. Added comments to explain myself. [V2] https://lore.kernel.org/all/20240514224508.212318-1-romank@linux.microsoft.com/ - Decreased number of #ifdef's - Updated the wording in the commit messages to adhere to the guidlines - Sending to the correct set of maintainers and mail lists [V1] https://lore.kernel.org/all/20240510160602.1311352-1-romank@linux.microsoft.com/ Roman Kisel (6): arm64: hyperv: Use SMCCC to detect hypervisor presence Drivers: hv: Enable VTL mode for arm64 Drivers: hv: Provide arch-neutral implementation of get_vtl() dt-bindings: microsoft,vmbus: Add GIC and DMA coherence to the example Drivers: hv: vmbus: Get the IRQ number from DeviceTree PCI: hv: Get vPCI MSI IRQ domain from DeviceTree .../bindings/bus/microsoft,vmbus.yaml | 11 +++ arch/arm64/hyperv/mshyperv.c | 43 ++++++++++-- arch/arm64/include/asm/mshyperv.h | 5 ++ arch/x86/hyperv/hv_init.c | 34 --------- drivers/hv/Kconfig | 10 +-- drivers/hv/hv_common.c | 32 +++++++++ drivers/hv/vmbus_drv.c | 59 +++++++++++++--- drivers/pci/controller/pci-hyperv.c | 69 +++++++++++++++++-- include/asm-generic/mshyperv.h | 6 ++ include/hyperv/hvgdk_mini.h | 2 +- include/linux/hyperv.h | 2 + 11 files changed, 215 insertions(+), 58 deletions(-) base-commit: 2e03358be78b65d28b66e17aca9e0c8700b0df78