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: 13970916 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 25E657080D; Wed, 12 Feb 2025 01:43:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739324605; cv=none; b=TDNJbDzAFZE4lJwR6t5PGKr4Zd2Tv6pv7/qa/GpZt4S1s5JV5WUO+I9gMrcDzednCAauxgufW7znmeqXp3qcOGeInc19WhdaApj9FP0qV61TvKrokJW2i5x8CBFkyE2SBMvXb73RYSlGTAVnfw5HDaJkK9L7EVmnmrnehBXwZ2o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739324605; c=relaxed/simple; bh=2x4lj5NC+dRFGIx4IzjaPe8yqSh4IK03MPDatQfBLq0=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=EhUwUPPyc0vm1ENoLXjEyGJWyY0bOG/nVTaK4jrUn/l3bVhi6cLy+Lgh9Ci/LrDHCAgCXmXuAn/+4rw/eWbZzYzv1ZcuKfSCypq1dHzDboBFDDy+7fjwT6sZh7yEfXIs5A+LepwXXz/uZ23wYo40H8QBcVmn4OgsJoZ2RKe7lNw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=DLTomIWn; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="DLTomIWn" 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 Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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