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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 202C810AB82B for ; Thu, 26 Mar 2026 22:25:05 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B7C216B00A4; Thu, 26 Mar 2026 18:24:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B05556B00A5; Thu, 26 Mar 2026 18:24:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9CD6D6B00A6; Thu, 26 Mar 2026 18:24:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 7EC446B00A4 for ; Thu, 26 Mar 2026 18:24:58 -0400 (EDT) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 5B2FE1A0E44 for ; Thu, 26 Mar 2026 22:24:58 +0000 (UTC) X-FDA: 84589645476.02.D7EEAA2 Received: from mail-pf1-f202.google.com (mail-pf1-f202.google.com [209.85.210.202]) by imf27.hostedemail.com (Postfix) with ESMTP id 7EB3E4000E for ; Thu, 26 Mar 2026 22:24:56 +0000 (UTC) Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=google.com header.s=20251104 header.b="bwoC/GAE"; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf27.hostedemail.com: domain of 3N7LFaQsKCAgiksmztm61voowwotm.kwutqv25-uus3iks.wzo@flex--ackerleytng.bounces.google.com designates 209.85.210.202 as permitted sender) smtp.mailfrom=3N7LFaQsKCAgiksmztm61voowwotm.kwutqv25-uus3iks.wzo@flex--ackerleytng.bounces.google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1774563896; a=rsa-sha256; cv=none; b=q7b2i/AEfUYVi6+OTII5Qwy+BPmvbpWXAPw1fABz6Wwajo9Gde8gmAgvEtdybp+j9qMFep EGR74c5ujZFgJN/HQzUSms8fzhf3kvD81GD+0bMf0vBAFODyKCTRVf3o/hNSdVSK4WR0d3 Vozq0+7KWrbc4zDmS7G9G+FgKoWsUmc= ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=google.com header.s=20251104 header.b="bwoC/GAE"; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf27.hostedemail.com: domain of 3N7LFaQsKCAgiksmztm61voowwotm.kwutqv25-uus3iks.wzo@flex--ackerleytng.bounces.google.com designates 209.85.210.202 as permitted sender) smtp.mailfrom=3N7LFaQsKCAgiksmztm61voowwotm.kwutqv25-uus3iks.wzo@flex--ackerleytng.bounces.google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1774563896; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=t5sAlrGE9K54t1wVa5MW/TMmXMtzYRZrp4A2ve/Zymo=; b=uHwkY6P8uaYIHc3j/m3dxkl4TgDu7GA5Gm6kx6eQgQxIo+nbHS/vkcsTONNeiDUTantcl8 i9S87F5UN/Y7CmLWNxyRu+8skT0iImgDCbLc4cYpvMKikYpYbstXI+uJC9o+BqHBDyZ0Ra gcpSb7Bec3eF4Qd/rQb+snY+FHreX/E= Received: by mail-pf1-f202.google.com with SMTP id d2e1a72fcca58-829b7ed8964so1449505b3a.2 for ; Thu, 26 Mar 2026 15:24:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1774563895; x=1775168695; darn=kvack.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=t5sAlrGE9K54t1wVa5MW/TMmXMtzYRZrp4A2ve/Zymo=; b=bwoC/GAEe82tAwmEkrrj81sowLm7EDnPUOf4UfRg9Hl2bXLvoHjYu3nlOEuygwtRLH jnPxyDLzn2f04hlkpw6xQtdbz6RUQCuCb01AvgGsTjHkNk6HxkOjExLHhyYMP2anq7jX PHdTAx/YFDhkODpJli6k63+Rvzy9eifGncu2yxDXRL+5C0umYXQcgAkKPP26g6+cXOaI k5RAQ/LWObGbdjPBfc7lQzsO776nbz+ZTGbGnonKDmS0Rm3nWbXkfa8Mdmbfhy+U+yvL Gub0pIotn5nBxwl8r0RtkOSCyq6ITqFmJIY1+RncVRHkCX5vzP/ogBKtCPfrvD/9HC65 JxKA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774563895; x=1775168695; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=t5sAlrGE9K54t1wVa5MW/TMmXMtzYRZrp4A2ve/Zymo=; b=WGeFGVzG88q0SXWoIr9EFV9dBksHXRMg3I7VCcT2U2gxPpfYUJc4U2sa8wCo5p3taN 9iARKFZmeB6z1AemaUHWXh+LW1jf0tG18vfrR+Oy1mjUXYA+XGImrnjBKFBk+R7cWnUT tdOH88/+ayCzKyP/LndYVakpDH1qML8WmfXC2zlZj4AXVdMLFv9JGSSarA9FUNu0F2/Q Y8Art0UTNe9blx0RAF8dVZmwHSA+AgEgOK8GmI84UZnZtsInsI9I3CthS2GNMCw775jJ k4zw7uypn/xiG9zG+s3NbtcQMnofnLLRRYDM5IKIJhjiA5P3rIFycpBHq2cRQHhbA09s T8Bg== X-Forwarded-Encrypted: i=1; AJvYcCUXm6vsCeL8cQruj3/EWmSIAQonXAETbGDquqIUkR4F+IsAoroNXGZl2IBRoeUmyiqeVIGtahvg8A==@kvack.org X-Gm-Message-State: AOJu0YxrjrJdU7jLWGzMKw66wjGs2m/r5LIA11Zd3Ek/Q+TfZS80WU/B E3qei0iGz5skIB+YmeI+6qeN8Anv8187e/GkZ/kKhBK9RtW0+EqDMH9SUPjjS9XV5QKL/6gDrM0 PoWQenHdlt5/Zqzt6aEgB/PaZfA== X-Received: from pfbfb15.prod.google.com ([2002:a05:6a00:2d8f:b0:829:9082:12ca]) (user=ackerleytng job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:bc81:b0:82a:81b6:d8a6 with SMTP id d2e1a72fcca58-82c95ed3b8amr136334b3a.25.1774563895023; Thu, 26 Mar 2026 15:24:55 -0700 (PDT) Date: Thu, 26 Mar 2026 15:24:24 -0700 In-Reply-To: <20260326-gmem-inplace-conversion-v4-0-e202fe950ffd@google.com> Mime-Version: 1.0 References: <20260326-gmem-inplace-conversion-v4-0-e202fe950ffd@google.com> X-Developer-Key: i=ackerleytng@google.com; a=ed25519; pk=sAZDYXdm6Iz8FHitpHeFlCMXwabodTm7p8/3/8xUxuU= X-Developer-Signature: v=1; a=ed25519-sha256; t=1774563861; l=2976; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=k0rIEhQmrf2G34ijeqLeCvTfDWOQ9le3qaLEQJYYHBc=; b=IWLi+POwxzAv6171snEkLJVWDYN28Uuep3Son7R0IlBi2Sc94mxhcktuxdQooqH4T04aDlDmq +h30zn8kj/LDlT1kMmeMRqgH+wx8i80pH8UDKHg1NuB4KJ+CpPgIlNh X-Mailer: b4 0.14.3 Message-ID: <20260326-gmem-inplace-conversion-v4-15-e202fe950ffd@google.com> Subject: [PATCH RFC v4 15/44] KVM: Add CAP to enumerate supported SET_MEMORY_ATTRIBUTES2 flags From: Ackerley Tng To: aik@amd.com, andrew.jones@linux.dev, binbin.wu@linux.intel.com, brauner@kernel.org, chao.p.peng@linux.intel.com, david@kernel.org, ira.weiny@intel.com, jmattson@google.com, jroedel@suse.de, jthoughton@google.com, michael.roth@amd.com, oupton@kernel.org, pankaj.gupta@amd.com, qperret@google.com, rick.p.edgecombe@intel.com, rientjes@google.com, shivankg@amd.com, steven.price@arm.com, tabba@google.com, willy@infradead.org, wyihan@google.com, yan.y.zhao@intel.com, forkloop@google.com, pratyush@kernel.org, suzuki.poulose@arm.com, aneesh.kumar@kernel.org, Paolo Bonzini , Sean Christopherson , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Jonathan Corbet , Shuah Khan , Shuah Khan , Vishal Annapurve , Andrew Morton , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Jason Gunthorpe , Vlastimil Babka Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, Ackerley Tng Content-Type: text/plain; charset="utf-8" X-Rspamd-Queue-Id: 7EB3E4000E X-Stat-Signature: qcwfkk881y9spq6uaehw5kqx3k8gmzbz X-Rspam-User: X-Rspamd-Server: rspam04 X-HE-Tag: 1774563896-403982 X-HE-Meta: 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 QGDkkG83 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Add CAP to enumerate supported SET_MEMORY_ATTRIBUTES2 flags, so userspace can find out which flags are supported when sending the KVM_SET_MEMORY_ATTRIBUTES2 ioctl to a guest_memfd. These flags are only supported by guest_memfd, hence, if vm_memory_attributes is enabled, return 0 - no flags are supported when KVM_SET_MEMORY_ATTRIBUTES2 is sent to a VM fd. Signed-off-by: Ackerley Tng --- Documentation/virt/kvm/api.rst | 3 +++ include/linux/kvm_host.h | 12 ++++++++++++ include/uapi/linux/kvm.h | 1 + virt/kvm/kvm_main.c | 5 +++++ 4 files changed, 21 insertions(+) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 90587a9c09d3f..73101d6e649b7 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -6680,6 +6680,9 @@ guarantees are made on offset ranges that do not have memory allocated and range [0x0000, 0x3000) was set to shared, the content mode would apply to only to offset ranges [0x0000, 0x1000) and [0x2000, 0x3000). +The supported content modes can be queried using +``KVM_CAP_MEMORY_ATTRIBUTES2_FLAGS``. + See also: :ref: `KVM_SET_MEMORY_ATTRIBUTES`. .. _kvm_run: diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 4ba3c4b303f4a..d671c9795dfce 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -2536,6 +2536,18 @@ static inline u64 kvm_supported_mem_attributes(struct kvm *kvm) return 0; } +static inline u64 kvm_supported_set_mem_attributes2_flags(struct kvm *kvm) +{ + if (!IS_ENABLED(CONFIG_KVM_GUEST_MEMFD)) + return 0; + + if (!kvm) + return KVM_SET_MEMORY_ATTRIBUTES2_ZERO | + KVM_SET_MEMORY_ATTRIBUTES2_PRESERVE; + + return kvm_arch_gmem_supported_content_modes(kvm); +} + typedef unsigned long (kvm_get_memory_attributes_t)(struct kvm *kvm, gfn_t gfn); DECLARE_STATIC_CALL(__kvm_get_memory_attributes, kvm_get_memory_attributes_t); diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 0fc9ad4ea0d93..4d1e09d022c48 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -991,6 +991,7 @@ struct kvm_enable_cap { #define KVM_CAP_S390_KEYOP 247 #define KVM_CAP_MEMORY_ATTRIBUTES2 248 #define KVM_CAP_GUEST_MEMFD_MEMORY_ATTRIBUTES 249 +#define KVM_CAP_MEMORY_ATTRIBUTES2_FLAGS 250 struct kvm_irq_routing_irqchip { __u32 irqchip; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 85c14197587d4..6607127eaaeed 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -4980,6 +4980,11 @@ static int kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg) return 0; return kvm_supported_mem_attributes(kvm); + case KVM_CAP_MEMORY_ATTRIBUTES2_FLAGS: + if (vm_memory_attributes) + return 0; + + return kvm_supported_set_mem_attributes2_flags(kvm); #endif default: break; -- 2.53.0.1018.g2bb0e51243-goog