From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DE2B4309F09; Sat, 26 Sep 2026 00:50:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790383851; cv=none; b=BecxuAdsN8kEGa5PDC4+N1lfu5o2WcU2Rp3d2vyuultAvFvrD0xHnzhUwy0agTWZ1PVQBiraEiF33AOIPFa7zAra/olzHr3rVWulajDSnutmnPG0y0ggdY1J6K+nLljzCVAG9aS9Lu4ug9ccJk9iq2NofoDj423fxbqTR1bahnY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790383851; c=relaxed/simple; bh=scd7V/LVJivphFiPiDvRuz42sItWihE//ekPollR9ww=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=svfcIsAkA6S9GXKDQzNHoYQCw+2Ckngm5KuPQViMf9F6WVVOk/I7JsKJXZ1e6J1K39Bv5Mx7Y6y8jCYo0VJBfCSGDuMDbbxA7M2/NDu2BP/cYbz0NxaIDrsiwgMy28EjMpTu2iVklBx9gf1Oi0fc23PcpLJZBKvnVm8SvwTpJPE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VlIbi7CG; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VlIbi7CG" Received: by smtp.kernel.org (Postfix) with ESMTPS id 98520C2BCB8; Sat, 26 Sep 2026 00:50:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1790383851; bh=scd7V/LVJivphFiPiDvRuz42sItWihE//ekPollR9ww=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=VlIbi7CGBVC1DMNetWyfB8xLyeMaQt84miSWHEyYRFw2SrAcS1IRXzGZVD5kNFnZe Qfr6jxWfKyVOu48L8NI+6XNPbbhz8RVqxXXlnN5MebjdTS8FuQ5+V5vM3tb5XV7tFy AhAspGmk90sOGAvjNcOvafwN6KcwenYmLqgrVqW3ept76WgZB5Uq1aPlFBaRGWLm2y KpaDU6EMC4s3Q3Ff3NWr3Vs63iTil8M9KskZXA5AV7U4njaOlke/AB9jMUeo87fdub wXahmRd/iKQKGwuJMbdSWgMIX4PoED9dGX33IzOpkkKUJNrZW5LcSpqdVdZGSRrFJ+ 0eZKZbqdZ5A0A== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 80CC7C98326; Sat, 26 Sep 2026 00:50:51 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Fri, 25 Sep 2026 17:50:52 -0700 Subject: [PATCH RFC 05/17] KVM: selftests: Add helper to create guest_memfd with a resource file Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260925-gmem-tmpfs-backend-v1-5-d36159822d18@google.com> References: <20260925-gmem-tmpfs-backend-v1-0-d36159822d18@google.com> In-Reply-To: <20260925-gmem-tmpfs-backend-v1-0-d36159822d18@google.com> To: Hugh Dickins , Baolin Wang , Andrew Morton , Sean Christopherson , Paolo Bonzini , David Hildenbrand , Jonathan Corbet , Shuah Khan , Randy Dunlap , Shuah Khan , vannapurve@google.com, erdemaktas@google.com, jxgao@google.com, rientjes@google.com, fvdl@google.com, jthoughton@google.com, tarunsahu@google.com, pratyush@kernel.org, fuad.tabba@linux.dev, Gregory Price , David Woodhouse , yan.y.zhao@intel.com, michael.roth@amd.com, suzuki.poulose@arm.com, Christian Brauner , Jason Gunthorpe , Nicolin Chen , Xu Yilun , aik@amd.com, aneesh.kumar@kernel.org, Vlastimil Babka Cc: kernel-team@android.com, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, Ackerley Tng X-Mailer: b4 0.17-dev X-Developer-Signature: v=1; a=ed25519-sha256; t=1790383850; l=2918; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=a/IEkQZJisftLh4S+E8BZovfShlWauj9NzlVULRnFLg=; b=7ARebru5UbY4aUsqapWdwIr6jjRLvLKYLPWf3bBzdcMmZAQ4uzWyZEWPEWNPpEI+RT7Pue/c9 2nchVurQunNCDcbczxcNhXiAZELx4OWz4fTcupDdwsNJ/jvk1VphSOc X-Developer-Key: i=ackerleytng@google.com; a=ed25519; pk=sAZDYXdm6Iz8FHitpHeFlCMXwabodTm7p8/3/8xUxuU= X-Endpoint-Received: by B4 Relay for ackerleytng@google.com/20260225 with auth_id=649 X-Original-From: Ackerley Tng Reply-To: ackerleytng@google.com From: Ackerley Tng Add a helper to create guest_memfd instances with a resource file descriptor, and update the existing creation helper to pass a zero resource file descriptor. Signed-off-by: Ackerley Tng --- tools/include/uapi/linux/kvm.h | 5 ++++- tools/testing/selftests/kvm/include/kvm_util.h | 23 ++++++++++++++++++----- 2 files changed, 22 insertions(+), 6 deletions(-) diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h index 419011097fa8e..66c1f40b50c29 100644 --- a/tools/include/uapi/linux/kvm.h +++ b/tools/include/uapi/linux/kvm.h @@ -1654,11 +1654,14 @@ struct kvm_memory_attributes { #define KVM_CREATE_GUEST_MEMFD _IOWR(KVMIO, 0xd4, struct kvm_create_guest_memfd) #define GUEST_MEMFD_FLAG_MMAP (1ULL << 0) #define GUEST_MEMFD_FLAG_INIT_SHARED (1ULL << 1) +#define GUEST_MEMFD_FLAG_USE_RESOURCE (1ULL << 2) struct kvm_create_guest_memfd { __u64 size; __u64 flags; - __u64 reserved[6]; + __s32 resource_fd; + __u32 pad; + __u64 reserved[5]; }; #define KVM_PRE_FAULT_MEMORY _IOWR(KVMIO, 0xd5, struct kvm_pre_fault_memory) diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h index 777fa3dbf88d6..9eeaefe5a1839 100644 --- a/tools/testing/selftests/kvm/include/kvm_util.h +++ b/tools/testing/selftests/kvm/include/kvm_util.h @@ -767,26 +767,39 @@ static inline bool is_smt_on(void) void vm_create_irqchip(struct kvm_vm *vm); -static inline int __vm_create_guest_memfd(struct kvm_vm *vm, u64 size, - u64 flags) +static inline int __vm_create_guest_memfd_resource(struct kvm_vm *vm, u64 size, + u64 flags, int resource_fd) { struct kvm_create_guest_memfd guest_memfd = { .size = size, .flags = flags, + .resource_fd = resource_fd, }; return __vm_ioctl(vm, KVM_CREATE_GUEST_MEMFD, &guest_memfd); } -static inline int vm_create_guest_memfd(struct kvm_vm *vm, u64 size, - u64 flags) +static inline int __vm_create_guest_memfd(struct kvm_vm *vm, u64 size, + u64 flags) +{ + return __vm_create_guest_memfd_resource(vm, size, flags, 0); +} + +static inline int vm_create_guest_memfd_resource(struct kvm_vm *vm, u64 size, + u64 flags, int resource_fd) { - int fd = __vm_create_guest_memfd(vm, size, flags); + int fd = __vm_create_guest_memfd_resource(vm, size, flags, resource_fd); TEST_ASSERT(fd >= 0, KVM_IOCTL_ERROR(KVM_CREATE_GUEST_MEMFD, fd)); return fd; } +static inline int vm_create_guest_memfd(struct kvm_vm *vm, u64 size, + u64 flags) +{ + return vm_create_guest_memfd_resource(vm, size, flags, 0); +} + void vm_set_user_memory_region(struct kvm_vm *vm, u32 slot, u32 flags, gpa_t gpa, u64 size, void *hva); int __vm_set_user_memory_region(struct kvm_vm *vm, u32 slot, u32 flags, -- 2.56.0.rc1.315.gc6ed9934b7-goog