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 17BE2CAC593 for ; Fri, 12 Sep 2025 08:56:05 +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=yhSXL+2pa9oDbDGRuQ4gQlpl18vQ+30/sPKc3K6z7Uo=; b=jCS9xmG35r+QmPlWe5PT675pDS hkekWz6LKBrjABjBLiRMLQsAFxllcE/F1rpH+TBGdWOet6L4AFJTK94zYpCX8RkbAKWbuvATpNJNF JCWMAsE8TM2RDGUTp5AaucBaG0hj+LGVRrF0PQYKrGIPoOXTVDCLmehfenWBBKlinYI1o2qtbhnC/ hLR5Kuxg13zL25MSt6Pgt5KRY1oLntQD2HBVw8ah7ZzXlTo1TD5gmcxilx9ql/oV9qjutrpxZcI1L LtiWckb/3cu23v2iyrZ4OyCbjZxQ91nk0aYnpUcKuud/HHE2haJ/VXjhsnMave1PUjuPNj6qLQktl Kx668asA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uwzZX-000000083LO-3vZQ; Fri, 12 Sep 2025 08:55:59 +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 1uwzZV-000000083K9-35Jv for linux-arm-kernel@lists.infradead.org; Fri, 12 Sep 2025 08:55:58 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1757667356; 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=yhSXL+2pa9oDbDGRuQ4gQlpl18vQ+30/sPKc3K6z7Uo=; b=IveBiTgu6K6wb46I3mtmTdpkQZdEaqeL7kwT/a8yxdSlKW8E78iZo7pxHlYZUQtPHxFiux ab9FzjtoPCb2eSDilf1UonpvzWM9HIJYBUUXLpll/e4fZlMu3/EBp+6NQjhHgc7kmlbz7v K1OjrPcQbN3bxuuhO2kLH+8V/cZFQEk= 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-199-cPEjnLF2OoiX3MfJ5RCY4Q-1; Fri, 12 Sep 2025 04:55:54 -0400 X-MC-Unique: cPEjnLF2OoiX3MfJ5RCY4Q-1 X-Mimecast-MFC-AGG-ID: cPEjnLF2OoiX3MfJ5RCY4Q_1757667353 Received: by mail-wm1-f71.google.com with SMTP id 5b1f17b1804b1-45b920a0c89so8406555e9.2 for ; Fri, 12 Sep 2025 01:55:54 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1757667353; x=1758272153; h=content-transfer-encoding:in-reply-to: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=yhSXL+2pa9oDbDGRuQ4gQlpl18vQ+30/sPKc3K6z7Uo=; b=cznEDLqkkGxwVfUseQhJH+B1p1EIw3Y7kYp61w8+tdGZi7vfkBG9vahWlOoahfWWFi 9Rp4BND8/6w8eIdtwZR26BTmJcedNLeBbcucaJHI+xnxCjgPqi9dLxE/xGCaFbSHfQlA OKA0hfbI8DkqkDNH5ZVU94/9ht3G8xISrX2ulAnOc8aWiMG6ZUWe9rUC28RnOeDc6mKP 7ij+7wuBGv6zTV8dWHcxcSJ8GUEcsGPsqOZe+M+7YHospDVGrvCmlWT9SZ8n9ftMk0Dd C3ZXs6mI//bUGfCm90hnZIvMe8OJisDeTCLVPmi1Ljp9uS+RPxS0WwHO2xUG9RQdSL+L pWxQ== X-Forwarded-Encrypted: i=1; AJvYcCX8WOZuCwElu65whVMHuHo3bRXW/1VtqYfUQMFSObr9TyfrxNKkhT2diqQat4LRTCemU5R9zbbbj5apUnrkxS6i@lists.infradead.org X-Gm-Message-State: AOJu0YyrZSc2uVg+uFb4PfP43UDW58+X4YZI5p5wzWcNFsQ/gQvWUCVt HOHN5S8220herIfcKWgFpBcAT92mNT+stmc7zCRO9TLVWwGTS49JUD/QunB651QQlOQcFy6LK3N wqoNqcn+AEsjlDlWbWwQSPtTxkevoWBBYWwsTINzN8Tuvy2iV8RV73A0LCjcmi/eooBhRFG8J2D zh X-Gm-Gg: ASbGncsE7426gLJaAm32Ir4Q5AVigmXzKzAD3KTPFYJPdM0e7fNoQ890miBAQj/mJW8 SnUCq+UC5SfMqw/0ylIbNTSmLkrXzuTKZhOE/4VR1K7yW21dPy4BCCNU7q0tq1omJM9ueXMf3Dw QSsIiLSR+CLfQNuNN5QO1883IfRe3KscfPGkjM6qhC7JHtRwX/O9KaOGJvH+7yzdaYNWDpXBE2p 3iNnSAGLElkvZ6zR7KDcS/OM6C98sLiv5iAArUUbY+559cdem2reThreb83ltH16FfGYokPWeRg ovE1twFgyfe66d8js3eyBA2FIfc1p432yUbmEvMbGRmLw/2A1UcFayzvEgfqDL5/BL7KyNZe9IU JKtdAlhQcP+EuaWyxBlrMgOZK4+vwKaHZzR0Xu9BNHZAnr9tCBg9KlKFhK1/E/M39SmQ= X-Received: by 2002:a05:600c:228f:b0:45b:6743:2242 with SMTP id 5b1f17b1804b1-45f211f86c5mr15325765e9.22.1757667353221; Fri, 12 Sep 2025 01:55:53 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGWDKbJzbJR4/u84XZSgPwx14/k9hN3sfQaLT2TQm5sKZh16Dp+Cgzni1IYyZJBI43U7rR/8A== X-Received: by 2002:a05:600c:228f:b0:45b:6743:2242 with SMTP id 5b1f17b1804b1-45f211f86c5mr15325425e9.22.1757667352826; Fri, 12 Sep 2025 01:55:52 -0700 (PDT) Received: from ?IPV6:2003:d8:2f20:da00:b70a:d502:3b51:1f2d? (p200300d82f20da00b70ad5023b511f2d.dip0.t-ipconnect.de. [2003:d8:2f20:da00:b70a:d502:3b51:1f2d]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-45e037c3ce5sm54255495e9.16.2025.09.12.01.55.50 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 12 Sep 2025 01:55:52 -0700 (PDT) Message-ID: Date: Fri, 12 Sep 2025 10:55:50 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/7] mm: introduce local state for lazy_mmu sections To: Kevin Brodsky , Alexander Gordeev Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andreas Larsson , Andrew Morton , Boris Ostrovsky , Borislav Petkov , Catalin Marinas , Christophe Leroy , Dave Hansen , "David S. Miller" , "H. Peter Anvin" , Ingo Molnar , Jann Horn , Juergen Gross , "Liam R. Howlett" , Lorenzo Stoakes , Madhavan Srinivasan , Michael Ellerman , Michal Hocko , Mike Rapoport , Nicholas Piggin , Peter Zijlstra , Ryan Roberts , Suren Baghdasaryan , Thomas Gleixner , Vlastimil Babka , Will Deacon , Yeoreum Yun , linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, xen-devel@lists.xenproject.org, Mark Rutland References: <20250908073931.4159362-1-kevin.brodsky@arm.com> <20250908073931.4159362-3-kevin.brodsky@arm.com> <2fecfae7-1140-4a23-a352-9fd339fcbae5-agordeev@linux.ibm.com> <47ee1df7-1602-4200-af94-475f84ca8d80@arm.com> <29383ee2-d6d6-4435-9052-d75a263a5c45@redhat.com> <9de08024-adfc-421b-8799-62653468cf63@arm.com> <4b4971fd-0445-4d86-8f3a-6ba3d68d15b7@arm.com> <4aa28016-5678-4c66-8104-8dcc3fa2f5ce@redhat.com> <15d01c8b-5475-442e-9df5-ca37b0d5dc04@arm.com> <7953a735-6129-4d22-be65-ce736630d539@redhat.com> <781a6450-1c0b-4603-91cf-49f16cd78c28@arm.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 ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZoEEwEIAEQCGwMCF4ACGQEFCwkIBwICIgIG FQoJCAsCBBYCAwECHgcWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaJzangUJJlgIpAAKCRBN 3hD3AP+DWhAxD/9wcL0A+2rtaAmutaKTfxhTP0b4AAp1r/eLxjrbfbCCmh4pqzBhmSX/4z11 opn2KqcOsueRF1t2ENLOWzQu3Roiny2HOU7DajqB4dm1BVMaXQya5ae2ghzlJN9SIoopTWlR 0Af3hPj5E2PYvQhlcqeoehKlBo9rROJv/rjmr2x0yOM8qeTroH/ZzNlCtJ56AsE6Tvl+r7cW 3x7/Jq5WvWeudKrhFh7/yQ7eRvHCjd9bBrZTlgAfiHmX9AnCCPRPpNGNedV9Yty2Jnxhfmbv Pw37LA/jef8zlCDyUh2KCU1xVEOWqg15o1RtTyGV1nXV2O/mfuQJud5vIgzBvHhypc3p6VZJ lEf8YmT+Ol5P7SfCs5/uGdWUYQEMqOlg6w9R4Pe8d+mk8KGvfE9/zTwGg0nRgKqlQXrWRERv cuEwQbridlPAoQHrFWtwpgYMXx2TaZ3sihcIPo9uU5eBs0rf4mOERY75SK+Ekayv2ucTfjxr Kf014py2aoRJHuvy85ee/zIyLmve5hngZTTe3Wg3TInT9UTFzTPhItam6dZ1xqdTGHZYGU0O otRHcwLGt470grdiob6PfVTXoHlBvkWRadMhSuG4RORCDpq89vu5QralFNIf3EysNohoFy2A LYg2/D53xbU/aa4DDzBb5b1Rkg/udO1gZocVQWrDh6I2K3+cCs7BTQRVy5+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: <781a6450-1c0b-4603-91cf-49f16cd78c28@arm.com> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 5wEkGcKU7aDPIy3T9ZoCw9hi5e8qY9hhHBjzKyyX1ng_1757667353 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-20250912_015557_841610_85ACA9DC X-CRM114-Status: GOOD ( 11.64 ) 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 > I also wondered about that. I think the safest is to make them > respectively arch_leave() and arch_enter() - the flushing entailed by > arch_leave() might not be required, but it is safer. Additionally, > powerpc/sparc disable preemption while in lazy_mmu, so it seems like a > good idea to re-enable it while paused (by calling arch_leave()). Great, looking forward to seeing this all getting cleaned up and done properly for good. -- Cheers David / dhildenb