From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 5091F3D969E; Mon, 31 Aug 2026 11:27:16 +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=1788175637; cv=none; b=qtdFnU6SNr3VZV2i0LFvsGuatUL1GYFXHT7hekSw1kdLKXJh8EbcMEB3evpGJc7wngQNQWgK1xzV3B6sc2sA9iD9J1+D4MsEJxzUHxRTZuxR2ovYUHOTHaM1p5Ro0+KdnklbmAWUcuUtHy9GRI4oo+BejTZLV91c1vQAZXXgkWE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788175637; c=relaxed/simple; bh=CXiKp3cZ09jf1dpkPnEk57IpxPBqd1hs15x1awALGus=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ht5QHbsudkdUdz/S44HBnsx0TwzY8Puy+Wp5IbVTt3Pfnw8h6iaDtaRTfj4hxb1WtIkWBD+PFkUbztvaubACokCzEzJiSlp31CzJmLzkVsEVr2fgfw8qfMsJIdQu77zv6vzH7nw1F4FFF9cWaxab6DozrVsRMTyBY8fTdhlYKWQ= 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=cZDFbiAX; 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="cZDFbiAX" Received: from weh-cvm-dev-vm.y50bckvjo0hefgfnzfztsfttff.phxx.internal.cloudapp.net (unknown [20.169.55.37]) by linux.microsoft.com (Postfix) with ESMTPSA id C2DE620B710C; Mon, 31 Aug 2026 04:26:39 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com C2DE620B710C DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1788175600; bh=gocMXCyvjmLDOe0RLsMl08gxUCa79z897Mw4qKKccg4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cZDFbiAXNuX+iir245Ba0sIC9twbHkiK8TEaizhQQoIIXCGCFV8uHjrrrNdrzEcRf dKKQ6B0oWJ/g65yc6xXrx5fycg+ywu8JGjHCT6CRXOaq6FxmaEiu1au9tfMxTG4Tt5 QEiyPBstBNx2+3Xd//yQ7kuwhlLgSrU050KiuMbI= From: Wei Hu To: linux-hyperv@vger.kernel.org Cc: linux-kernel@vger.kernel.org, "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Long Li Subject: [PATCH v4 0/9] mshv: add SEV-SNP support for MSHV root partitions Date: Mon, 31 Aug 2026 11:26:38 +0000 Message-ID: <20260831112704.2851147-1-weh@linux.microsoft.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260825040505.826600-1-weh@linux.microsoft.com> References: <20260825040505.826600-1-weh@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-hyperv@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit This series adds support for creating and managing AMD SEV-SNP confidential virtual machines through the Microsoft Hypervisor root partition driver. The series adds fixed-size MSHV UAPI definitions, the required Microsoft Hypervisor ABI definitions and hypercall helpers, partition ioctls, capability discovery, processor-feature handling, ordered encrypted-memory teardown, and nested-root SynIC handling. Two prerequisite fixes now lead the series. The first makes memory-region unmap ownership explicit and retains mappings, pinned pages, the partition, and the module whenever checked hypervisor unmap cannot prove cleanup. The second publishes and withdraws per-CPU SynIC pointers so interrupt readers cannot observe mappings after initialization failure or CPU teardown. The patches are based on the current hyperv-next branch. Testing: - Built all four affected x86 MSHV objects at every commit. - Built the complete x86_64 kernel and the affected objects with W=1. - Ran scripts/checkpatch.pl --strict on every patch with zero findings. - Verified installed UAPI layouts in 64-bit and 32-bit userspace builds. - Generated rust-vmm MSHV bindings from the installed kernel headers. - Built the affected ARM64 objects with W=1 and no warnings. - Passed Cloud Hypervisor's common_cvm::test_focal_simple_launch. - Booted a four-vCPU SEV-SNP guest to login. The development host needs two additional local runtime patches to boot as a nested MSHV root partition: EFI HvLoader root-partition boot enablement and the non-upstreamable nested-VMBus interrupt-vector workaround. Neither patch is part of this series. Changes since v3: - Add checked memory-region unmap ownership as prerequisite patch 1. Keep pages pinned and quarantine uncertain setup or teardown instead of freeing memory that may remain child-accessible. - Add SynIC pointer publication/withdrawal cleanup as prerequisite patch 2. - Rate-limit guest-triggerable PSP and isolated-page hypercall errors. - Publish and consume driver readiness with release/acquire ordering. - Make both array ioctls _IOWR interfaces with an MBZ input/completed output field, exact resumable progress, and defined no-rollback semantics. - Preserve the exact asynchronous completion result, encode only bounded repetition progress, and keep the distinct substatus out of result bits. - Check setup, explicit unmap, and teardown transitions; preserve list and kref ownership and quarantine any state whose safe release is uncertain. - Unmap child mappings before restoring host access for uninitialized as well as initialized SNP partitions. - Map hypervisor SynIC pages as decrypted shared-GPA mappings and withdraw per-CPU pointers before unmapping or freeing them. - Validate VMSA and PSP GPAs before PFN conversion and retain the existing large-page alignment and physical-contiguity checks. - Reject SNP isolation in intermediate commits until its complete ioctl and lifecycle implementation is present. - Guard the SNP-only GPFN conversion helper so ARM64 W=1 builds do not emit an unused-function warning. - Resolve additional adversarial-review findings: initialize common region locks for every region type, avoid mmap/remap lock inversion, validate zero/oversized REP progress, and initialize all common copyout paths. Two Sashiko findings were investigated and dismissed rather than papered over. Hyper-V consumes the PSP request input synchronously before returning HV_STATUS_CALL_PENDING, so the shared per-CPU input page need not remain reserved while waiting for completion. Also, MSHV's modify-SPA-host-access operation transfers root-to-child SPA/SLAT ownership in Hyper-V; it does not perform an in-place SNP RMP transition on Linux-owned direct-map pages, so kernel direct-map invalidation, encryption-attribute changes, and shared-bit rewrites would be incorrect here. Link: https://lore.kernel.org/linux-hyperv/20260825040505.826600-1-weh@linux.microsoft.com/ Wei Hu (3): mshv: retain memory regions until unmap succeeds mshv: clear SynIC mappings before freeing them mshv: set up own SynIC registers on a nested root partition Wei Liu (6): mshv: add SEV-SNP UAPI definitions mshv: add SEV-SNP PSP request hypercall mshv: add SEV-SNP isolated page hypercalls mshv: wire SEV-SNP partition ioctls mshv: detect and report SEV-SNP support at init mshv: use safe partition CPU feature defaults drivers/hv/mshv_regions.c | 160 +++-- drivers/hv/mshv_root.h | 50 +- drivers/hv/mshv_root_hv_call.c | 303 +++++++-- drivers/hv/mshv_root_main.c | 1045 +++++++++++++++++++++++++++++--- drivers/hv/mshv_synic.c | 172 +++--- include/hyperv/hvgdk_mini.h | 31 + include/hyperv/hvhdk.h | 124 +++- include/hyperv/hvhdk_mini.h | 53 ++ include/uapi/linux/mshv.h | 111 +++- 9 files changed, 1813 insertions(+), 236 deletions(-) base-commit: be0cfab740e58b70047ef6e7e3d578f00ed5d258 -- 2.43.0