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 AD98EC5AC82 for ; Mon, 10 Aug 2026 08:35:29 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 643A26B007B; Mon, 10 Aug 2026 04:35:28 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5F4876B008A; Mon, 10 Aug 2026 04:35:28 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 495356B008C; Mon, 10 Aug 2026 04:35:28 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 142BC6B007B for ; Mon, 10 Aug 2026 04:35:28 -0400 (EDT) Received: from smtpin05.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 846D5C06BA for ; Mon, 10 Aug 2026 08:35:27 +0000 (UTC) X-FDA: 85084700694.05.F1961E4 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf01.hostedemail.com (Postfix) with ESMTP id B952640010 for ; Mon, 10 Aug 2026 08:35:25 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="TQmWaY/e"; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf01.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1786350925; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Y2FLsoZ1hEB5Du7Ei8cxJVdd7PKne1YvDU/GLmcRPOo=; b=Fk62hz4X+37QzqxtQHYWehXG+g6unoZGZM8FV0uSENOE2jRPpOE8sg2OfOh6lqASMOnymZ cdTgGR9bFm3GrLyTFrfH+N2j9BsYvWf0TTV4w/Go/LMyHYtC1F/L0LoFZ0iFa5KmNIy1gB AO3aOfTrhRN1YmVtW8MxUwCa6Yfvy78= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="TQmWaY/e"; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf01.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1786350925; b=MGuiA2RelEDggumaFcnexQNsYiJCwMk/kA/YwxAjCNrGMqhOdt3d7yWGrmDaXuNsDR1Zk5 11LHJ+hPtJN14XPG2JcclP11PgkeT1oPSRe3yaK+Qpi87tkUnw3BD4OSrW5cAE+tc1eArk Fwzx/6oOlxETIbpERjJl+xtT4ykUUS8= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 404A960052; Mon, 10 Aug 2026 08:35:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 901641F000E9; Mon, 10 Aug 2026 08:35:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786350925; bh=Y2FLsoZ1hEB5Du7Ei8cxJVdd7PKne1YvDU/GLmcRPOo=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=TQmWaY/eJ/3bBk6gG8TZU/y84g0uAlRWwjgXzO3uFjLziwWv6qtrOxq74w4RVQead nFy1GVDQGRACN7JTwGwGV0fhqyZs6nw8zC/FE1OF1LI6hDDHqjPV6n386IOqpB6xJv DJIFqitE6qS+ErJjdv0VfhVoURCZ01vn9tSqDk+BzfxmORZoiUHqsAcuMKTkLDBUM+ mK/qYI1NcTvDICGR11N7UctnrdUA34YJ2xIsiv37jMDFEPHxI1BQ0vXevu23qY/W5K 8ZIYKAw+Mn8yyAdDFIcbq8k2g4GmRWmtk9ebvuwD9PEupqgK9sCowzxWKA38MuueII uw0AbLCKwziXg== Message-ID: <98d6b8c9-4c61-41ea-8585-1bfdb3347b7d@kernel.org> Date: Mon, 10 Aug 2026 10:35:04 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v9 06/41] KVM: guest_memfd: Introduce function to check GFN private/shared status To: ackerleytng@google.com, aik@amd.com, andrew.jones@linux.dev, binbin.wu@linux.intel.com, brauner@kernel.org, chao.p.peng@linux.intel.com, jmattson@google.com, 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, liam@infradead.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 , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Youngjun Park , Qi Zheng , Shakeel Butt , Kiryl Shutsemau , Baoquan He , Jason Gunthorpe , John Hubbard , Peter Xu , 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, linux-coco@lists.linux.dev, Xiaoyao Li References: <20260728-gmem-inplace-conversion-v9-0-35f9aec2aed2@google.com> <20260728-gmem-inplace-conversion-v9-6-35f9aec2aed2@google.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <20260728-gmem-inplace-conversion-v9-6-35f9aec2aed2@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: i81nwm1hh1tzndga1yxj4zedztacr4en X-Rspamd-Queue-Id: B952640010 X-HE-Tag: 1786350925-168911 X-HE-Meta: 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 0ESkXjL8 0FSiwQyvcGliAotuBI7ITS5GPd9w7rWatM421skJZFpYwB8fbkCvxO+oQ0kWM+qAgLLqxnkfalXAjq24pCiNE2x2til802Vsk0VdD63EB/tuElXsmb7ZiuRDNkMn9UT15zp7G7sXY86PFJJHhAFPuT4+zlFdOutWdFmpJkQAssrNz0GPO1Aw48iKSxHlk5P7V0rPqlSP1BpL977cGHWOlb+vqw4zcw6Ljhc196Q3vK9BdEBjVKfmvKDflS7ohYMAj9Blsk1+IwE7c7AR213E4QlTXG5Ut8/Or9xhO3Jdr4GlxO+Wihf/BneyINX6/L51x1YIxygnvmXA0/XQg/MxBuLGnw60HL0EOsQxJu6pQtd3aEpepBdlYjx5H+tweEt/fpOId Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 7/29/26 02:35, Ackerley Tng via B4 Relay wrote: > From: Ackerley Tng > > Introduce a function for KVM to check the private/shared status of guest > memory at a given GFN. > > This will be used in a later patch. > > Co-developed-by: Sean Christopherson > Signed-off-by: Sean Christopherson > Reviewed-by: Xiaoyao Li > Reviewed-by: Fuad Tabba > Tested-by: Shivank Garg > Signed-off-by: Ackerley Tng > --- > include/linux/kvm_host.h | 2 ++ > virt/kvm/guest_memfd.c | 32 ++++++++++++++++++++++++++++++++ > 2 files changed, 34 insertions(+) > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index 438567e3fa6a1..73f564b87a324 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -2594,6 +2594,8 @@ static inline bool kvm_mem_is_private(struct kvm *kvm, gfn_t gfn) > #endif /* kvm_arch_has_private_mem */ > > #ifdef CONFIG_KVM_GUEST_MEMFD > +bool kvm_gmem_is_private(struct kvm *kvm, gfn_t gfn); > + > int kvm_gmem_get_pfn(struct kvm *kvm, struct kvm_memory_slot *slot, > gfn_t gfn, kvm_pfn_t *pfn, struct page **page, > int *max_order); > diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c > index 8c7709a352cc7..33c9830190e2e 100644 > --- a/virt/kvm/guest_memfd.c > +++ b/virt/kvm/guest_memfd.c > @@ -474,6 +474,38 @@ static int kvm_gmem_mmap(struct file *file, struct vm_area_struct *vma) > return 0; > } > > +bool kvm_gmem_is_private(struct kvm *kvm, gfn_t gfn) The function name makes is sound like we are testing whether a kvm_gmem instance is private. The common code functions are kvm_mem_is_private and kvm_vm_mem_is_private So I would expect this here to be called kvm_gmem_mem_is_private But then, it's confusing that there is kvm_gmem_is_private_mem() already, which the new function calls. Maybe we have to indicate for the latter that it works on the inode? kvm_gmem_inode_mem_is_private() ? -- Cheers, David