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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A5E8EC8303D for ; Fri, 4 Jul 2025 14:28:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=xf17P1YALsimhDT+/HwyPfAob6T0qJHwLHeouZenqkI=; b=s3raNOpiV8cZ+mEM5k/UVR2uRN kx38/kZcAXL8p5mG0JFBGCRAJyu1cVVpVM6buMHMi3u27+Ibe58N5Gvb09TOoJIR4yOfs/bHkOEjc cCgQZEkFyhKInGnxsDgnIE6gxhOPIlZ7R6SFC8AwB71zn0h6yPxlqbSEQVs8qR9GRHYkvlUiJjpJw c0FGRmHFhq7qZN+2HrVrRNJDf3Ro8sIEWS5KyAd7ZMzQaT6lECiQUJBEAEve7djdWKzmYTGY7Kksi tZ+H4mJ7hyDl1fDWJ1l84Y52Lx/c7RMTG3KQ+oV68B7a59PJAc77U/CPLam7g/RaPUqpiFae2nxKD sdPYiW5g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uXhOp-0000000Efj4-3xJb; Fri, 04 Jul 2025 14:28:23 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uXh7c-0000000EcsI-38GX for linux-arm-kernel@lists.infradead.org; Fri, 04 Jul 2025 14:10:38 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1751638235; h=from:from: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:autocrypt:autocrypt; bh=xf17P1YALsimhDT+/HwyPfAob6T0qJHwLHeouZenqkI=; b=VCXImboaWeLzwW0ZJv5IdytfajfM72IKMkQXSQxrgFm2N8sbxpoAZ+9Dr2C8yLh57JMi0R DP4bTOdV6NXJ1cxOrYp5cwqgu0jTYVwWyR/tIGCvYuDS7ftW5uCd0dPYFh2tV91HTInif/ oQIUBrq2UD3Q7L3SRZgCOrTPkr0gWDg= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-391-O6yZE-auNJmkwFmuXQ3eNA-1; Fri, 04 Jul 2025 10:10:34 -0400 X-MC-Unique: O6yZE-auNJmkwFmuXQ3eNA-1 X-Mimecast-MFC-AGG-ID: O6yZE-auNJmkwFmuXQ3eNA_1751638234 Received: by mail-wm1-f71.google.com with SMTP id 5b1f17b1804b1-451d5600a54so8052165e9.2 for ; Fri, 04 Jul 2025 07:10:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751638233; x=1752243033; h=content-transfer-encoding:in-reply-to:organization:autocrypt :content-language:from:references:cc:to:subject:user-agent :mime-version:date:message-id:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=xf17P1YALsimhDT+/HwyPfAob6T0qJHwLHeouZenqkI=; b=LIKaO97Kjt6PB/9OOaHuRPjuNBKdHLQLLaMCzWSzT7YacXazVbiTEW1B2exZOon5Lt fUD4MLKgm9vSEZLIQVbxTkxFM1NGDAKI9/IKrBSlgoq0BhADFq44lmuxSNTqbJRq7Vd+ K95rz88ETaJb1zD/DHICg0OLJ3byKyjQ5AloDNFgfMwsQuOz/B7+fLvpJKv9cHI5OeEE E/JngIrGf9RzFY/xNk+cS9iy0+Dn4PZR/7NM2sZYgxm108g08fZfT59AXD568Ou5Fp7G S1NCGOVMl/Vcd2fzJPnLIAw52q9/XKaXavSmDBj8DjHEZGUwz+EEtTZ4YMcDnS4ZEKfK YrVg== X-Forwarded-Encrypted: i=1; AJvYcCVYXOfaaOATfN/OwMyoAkNuwIQwaJkLz6fhxJv79xxVOKgFHAj8hDFZZg+9sL9Lj0JkzVXHb+G7mUI8VfgFLI6D@lists.infradead.org X-Gm-Message-State: AOJu0YzNRpnvBc5H9a9pYdQbS9hLON0BGX7O2gOZ6mDymnawZ02/RHfn Goa1E0m/SDocRSdbcDjLCY9TlQKKmb5i6cSAJwFH70MAHxl44NRnVTKo4mbxOZF+0jAUgEqyE7k o8K+qW67vIt772MzmXo6aD4lSVw473Po7WvynPrpA9q1c+zjzOJj+MKYp7gVB/bA65DujedSkml YR X-Gm-Gg: ASbGnctq2qnHz/Eu7XDrtSi/L8Cp9ao8/H1KpzgmUO/fJB+90dpGfSuokvRt+4ADL5h E2ss9ShH5aCJ06+8vx/fGf4Uzg4DPDeiCoPVj0oIRhMe/On0usD6vovY1YFXoAHYG1kQ4mpSXpN lfMDlMWMRVQLpzWYpq3spK9BuYPirPRcsiQyEQr8ue4dnaj9xxOUI2un5fCKTnQnOEh8QL7n9F0 vSGZG4sNbA21ILONZLiT2lZZj1xQY6FuNyehl+fIofFp2Oo8VPKZg3laJal2S1TL9w/0BPptLn1 tqIzb4QCZayUSqq6aGo/5JXQOr38j2KUpWVrRqL6vVRRBmU1pekP//reL9TgJfE9+JH9wtiDsSM 7yV3b7WHvp9Emsu8A63PIqH8SPCOpAi5I8kb2bRiai7YyeyA= X-Received: by 2002:a05:600c:3ba5:b0:43d:4686:5cfb with SMTP id 5b1f17b1804b1-454b3b8a45emr27030685e9.27.1751638233335; Fri, 04 Jul 2025 07:10:33 -0700 (PDT) X-Google-Smtp-Source: AGHT+IHsqbZf4RF6qO+LIbhyPLm8ae++HUsMG9OIMJY26dMAgU/68GqU2/mlOykgqK3yE46NGChe4g== X-Received: by 2002:a05:600c:3ba5:b0:43d:4686:5cfb with SMTP id 5b1f17b1804b1-454b3b8a45emr27029925e9.27.1751638232755; Fri, 04 Jul 2025 07:10:32 -0700 (PDT) Received: from ?IPV6:2003:d8:2f2c:5500:988:23f9:faa0:7232? (p200300d82f2c5500098823f9faa07232.dip0.t-ipconnect.de. [2003:d8:2f2c:5500:988:23f9:faa0:7232]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-454a997ae2esm56138585e9.9.2025.07.04.07.10.30 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 04 Jul 2025 07:10:32 -0700 (PDT) Message-ID: <7ccee3be-6438-462d-8dce-efa58238f28d@redhat.com> Date: Fri, 4 Jul 2025 16:10:30 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v9 4/6] KVM: arm64: New function to determine hardware cache management support To: ankita@nvidia.com, jgg@nvidia.com, maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, ryan.roberts@arm.com, shahuang@redhat.com, lpieralisi@kernel.org, ddutile@redhat.com, seanjc@google.com Cc: aniketa@nvidia.com, cjia@nvidia.com, kwankhede@nvidia.com, kjaju@nvidia.com, targupta@nvidia.com, vsethi@nvidia.com, acurrid@nvidia.com, apopple@nvidia.com, jhubbard@nvidia.com, danw@nvidia.com, zhiw@nvidia.com, mochs@nvidia.com, udhoke@nvidia.com, dnigam@nvidia.com, alex.williamson@redhat.com, sebastianene@google.com, coltonlewis@google.com, kevin.tian@intel.com, yi.l.liu@intel.com, ardb@kernel.org, akpm@linux-foundation.org, gshan@redhat.com, linux-mm@kvack.org, tabba@google.com, qperret@google.com, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, maobibo@loongson.cn References: <20250621042111.3992-1-ankita@nvidia.com> <20250621042111.3992-5-ankita@nvidia.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; 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 B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: <20250621042111.3992-5-ankita@nvidia.com> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: l1gD2fL-BqrNcb8WDeoWfvm7JEOfoWXKxf3m16oboHM_1751638234 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250704_071036_864742_054BE468 X-CRM114-Status: GOOD ( 17.70 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 21.06.25 06:21, ankita@nvidia.com wrote: > From: Ankit Agrawal > > VM_PFNMAP VMA's are allowed to contain PTE's which point to physical > addresses that does not have a struct page and may not be in the kernel > direct map. > > However ARM64 KVM relies on a simple conversion from physaddr to a > kernel virtual address when it does cache maintenance as the CMO > instructions work on virtual addresses. This simple approach does not > work for physical addresses from VM_PFNMAP since those addresses may > not have a kernel virtual address, or it may be difficult to find it. > > Fortunately if the ARM64 CPU has two features, S2FWB and CACHE DIC, > then KVM no longer needs to do cache flushing and NOP's all the > CMOs. This has the effect of no longer requiring a KVA for addresses > mapped into the S2. > > Add a new function, kvm_arch_supports_cacheable_pfnmap(), to report > this capability. From a core prespective it means the arch can accept > a cachable VM_PFNMAP as a memslot. From an ARM64 perspective it means > that no KVA is required. > > CC: Jason Gunthorpe > CC: David Hildenbrand > CC: Donald Dutile > Reviewed-by: Catalin Marinas > Signed-off-by: Ankit Agrawal > --- Reviewed-by: David Hildenbrand -- Cheers, David / dhildenb