From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 90DA726E17D for ; Wed, 6 Aug 2025 12:24:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754483076; cv=none; b=BRtAaouD5BPFlLQTZYGQ110OYt1/P/7c8P9aynZO1rBRvb88gMSe+1DDVHzRiC4+JFmazEzAbcA7VCXKWmbKpFoxWwnu39dMMegO+G9Az+/gq3HSMhHai+KMEQx3TVMub37IPQsBlwiyNz0cD+OCFxVs2cCXYlTSQW8lzt7pqIw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754483076; c=relaxed/simple; bh=LaljGpMWj+4OiaGSSJjJcPcWCUIs8VI4+fvYOgA21Og=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=bJ3k9hVddgAJlAubY5DskxZ/UPrHXuM1AmMGSYLrjgO5SWQLGP1BuP7fBmphUBC9UYQ2Dj65IXv6599K3Cl9qfKWe9E6s255LzEckFo2GNrQAJwyK5lpmJzoCA4xJDuRcw93TTJfRgTFsYAns69CmHTY6JB+luKYKTqqxx2W8rg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=YaskYnvr; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="YaskYnvr" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1754483073; 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=MIyj2Wn/9XHAni6aZsxrY9Shasga7/OI8hKW0Eid1vw=; b=YaskYnvralkchzlM6QNLsmGMCvm4YXQey1Yftyagk0/UNbc5E/JTq9crHzoKPmDKi8Z39u q2lHgmvQZFjlIgCy/jqpKG1lXJiHYU40oiAo1bo+RAMFTDXIZSpfZBb4V5DxFz2+3CvK5B 62lShQ8qCQ5rPt8JUmrOrGV3Gg6UxfI= Received: from mail-wr1-f70.google.com (mail-wr1-f70.google.com [209.85.221.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-1-X7BrFPPrOr6aely5-JszrA-1; Wed, 06 Aug 2025 08:24:32 -0400 X-MC-Unique: X7BrFPPrOr6aely5-JszrA-1 X-Mimecast-MFC-AGG-ID: X7BrFPPrOr6aely5-JszrA_1754483071 Received: by mail-wr1-f70.google.com with SMTP id ffacd0b85a97d-3b780da0ab6so2921533f8f.0 for ; Wed, 06 Aug 2025 05:24:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1754483071; x=1755087871; 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=MIyj2Wn/9XHAni6aZsxrY9Shasga7/OI8hKW0Eid1vw=; b=jnS+mZKb0nUvGGXrHJWlYvjawwX6Ztj3cQi2+yfFh4uUHJmkV+LM2w9dbfnzXMIQDc zLvp7j2mX+WRAc5YrND5R7wzlMa15f0NOn0h9HfE9DvUhlW1MGya4QRT/m1wBbj3Q+ar xUo58EY8kiQZefhOOh7s210l5JWojNUxSLfHE5ha3g4INKgjOrmjJ7bJlYlOg8jEjhMp QLhPvKP7QwYAkV1IUog6FqjSgY171g2/w8cdUq2tTsrwVMQjAFKUk6G3QfqvKl1dhpvG /RkXQxaPtW4G5Jkbgorpvchv/fuKR5ibiAmlNtyMtv5JGZXwwD91V3araIK2VVcLGfx4 0pDQ== X-Forwarded-Encrypted: i=1; AJvYcCWXHM6xl2qylLoc783abpdfyBw0FQMk9jtked3TkeWlKNUQXX8jVR+M54RDxfi1N46Rd//dLKiBKNQFnes=@vger.kernel.org X-Gm-Message-State: AOJu0YxkRTG2M0OoQXPYUYxLAON34zQvdCEykTnBAEN1dhfQgNTKhIGG 6wpf8DHSrvPRVtWYSi3bL2zjt3yZJihIXXQBteNr79wbhm8fLoCmgDD0VyuBY3f1tSMrjPv/rwU Z6LEluIQholHrXGDVEsVqw4Mnr2sP1qnbVk7ABM1jUttsBPGCmcPMJA7/lE6zLI0uhg== X-Gm-Gg: ASbGnctazaUfmFwm6B1CYBgm8MADyimw4lIdircqqOsbb9K59Z9mpBWNrpK9IIr4Y2V R0qs3h0Cdy1j1u/kekzwq6TOlg8Aw9DvOhswL2+2axJWUpdxQWGr1H1VllGmYpdqh+OqG/3+Bn6 KM1YOn9TU3IwuhL4tMYZd+nVVfHup9bDU6SbN6wFh7wGccg8qHkPawlAOCoK43037P8Sx8aWF/T CVkqeuwXLdssDKLn/8vfDfWRG4EayK312pot7Gies5a+1C1x3zPemEke/ma3d5lLwIKI6LkWiTA Bdo50+vuu9VOYW6yWusvR7nZjag/Bn9BHuljdWqPnaKRbkF+FG/s94DDO6VkF79IeWV2c8AfFqd Piv73G7kYdYcYYnCrsgswcYDwJw1KqQ2MIezg5UgxYs5eJcfTia90YZqJ+axpmzEUuD4= X-Received: by 2002:a05:6000:4027:b0:3b7:8b2e:cc5a with SMTP id ffacd0b85a97d-3b8f41b503dmr2340142f8f.40.1754483071339; Wed, 06 Aug 2025 05:24:31 -0700 (PDT) X-Google-Smtp-Source: AGHT+IEbbEMbCT2awtezRB1880Ia/u3kJMAjx+ivYlRRgkF2JNcEjHJ04sShVIDm9LiLrdVjbATLeQ== X-Received: by 2002:a05:6000:4027:b0:3b7:8b2e:cc5a with SMTP id ffacd0b85a97d-3b8f41b503dmr2340112f8f.40.1754483070912; Wed, 06 Aug 2025 05:24:30 -0700 (PDT) Received: from ?IPV6:2003:d8:2f35:8a00:42f7:2657:34cc:a51f? (p200300d82f358a0042f7265734cca51f.dip0.t-ipconnect.de. [2003:d8:2f35:8a00:42f7:2657:34cc:a51f]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3b79c3bc12csm23360857f8f.28.2025.08.06.05.24.29 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 06 Aug 2025 05:24:30 -0700 (PDT) Message-ID: Date: Wed, 6 Aug 2025 14:24:28 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 3/5] mm: add static huge zero folio To: "Pankaj Raghav (Samsung)" Cc: Lorenzo Stoakes , Suren Baghdasaryan , Ryan Roberts , Baolin Wang , Borislav Petkov , Ingo Molnar , "H . Peter Anvin" , Vlastimil Babka , Zi Yan , Mike Rapoport , Dave Hansen , Michal Hocko , Andrew Morton , Thomas Gleixner , Nico Pache , Dev Jain , "Liam R . Howlett" , Jens Axboe , linux-kernel@vger.kernel.org, linux-mm@kvack.org, willy@infradead.org, x86@kernel.org, linux-block@vger.kernel.org, Ritesh Harjani , linux-fsdevel@vger.kernel.org, "Darrick J . Wong" , mcgrof@kernel.org, gost.dev@samsung.com, hch@lst.de, Pankaj Raghav References: <20250804121356.572917-1-kernel@pankajraghav.com> <20250804121356.572917-4-kernel@pankajraghav.com> <4463bc75-486d-4034-a19e-d531bec667e8@lucifer.local> <70049abc-bf79-4d04-a0a8-dd3787195986@redhat.com> <6ff6fc46-49f1-49b0-b7e4-4cb37ec10a57@lucifer.local> From: David Hildenbrand Content-Language: en-US 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/g1oFAmgsLPQFCRvGjuMACgkQTd4Q 9wD/g1o0bxAAqYC7gTyGj5rZwvy1VesF6YoQncH0yI79lvXUYOX+Nngko4v4dTlOQvrd/vhb 02e9FtpA1CxgwdgIPFKIuXvdSyXAp0xXuIuRPQYbgNriQFkaBlHe9mSf8O09J3SCVa/5ezKM OLW/OONSV/Fr2VI1wxAYj3/Rb+U6rpzqIQ3Uh/5Rjmla6pTl7Z9/o1zKlVOX1SxVGSrlXhqt kwdbjdj/csSzoAbUF/duDuhyEl11/xStm/lBMzVuf3ZhV5SSgLAflLBo4l6mR5RolpPv5wad GpYS/hm7HsmEA0PBAPNb5DvZQ7vNaX23FlgylSXyv72UVsObHsu6pT4sfoxvJ5nJxvzGi69U s1uryvlAfS6E+D5ULrV35taTwSpcBAh0/RqRbV0mTc57vvAoXofBDcs3Z30IReFS34QSpjvl Hxbe7itHGuuhEVM1qmq2U72ezOQ7MzADbwCtn+yGeISQqeFn9QMAZVAkXsc9Wp0SW/WQKb76 FkSRalBZcc2vXM0VqhFVzTb6iNqYXqVKyuPKwhBunhTt6XnIfhpRgqveCPNIasSX05VQR6/a OBHZX3seTikp7A1z9iZIsdtJxB88dGkpeMj6qJ5RLzUsPUVPodEcz1B5aTEbYK6428H8MeLq NFPwmknOlDzQNC6RND8Ez7YEhzqvw7263MojcmmPcLelYbfOwU0EVcufkQEQAOfX3n0g0fZz 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+DWgUCaCwtJQUJG8aPFAAKCRBN3hD3AP+DWlDnD/4k2TW+HyOOOePVm23F5HOhNNd7nNv3 Vq2cLcW1DteHUdxMO0X+zqrKDHI5hgnE/E2QH9jyV8mB8l/ndElobciaJcbl1cM43vVzPIWn 01vW62oxUNtEvzLLxGLPTrnMxWdZgxr7ACCWKUnMGE2E8eca0cT2pnIJoQRz242xqe/nYxBB /BAK+dsxHIfcQzl88G83oaO7vb7s/cWMYRKOg+WIgp0MJ8DO2IU5JmUtyJB+V3YzzM4cMic3 bNn8nHjTWw/9+QQ5vg3TXHZ5XMu9mtfw2La3bHJ6AybL0DvEkdGxk6YHqJVEukciLMWDWqQQ RtbBhqcprgUxipNvdn9KwNpGciM+hNtM9kf9gt0fjv79l/FiSw6KbCPX9b636GzgNy0Ev2UV m00EtcpRXXMlEpbP4V947ufWVK2Mz7RFUfU4+ETDd1scMQDHzrXItryHLZWhopPI4Z+ps0rB CQHfSpl+wG4XbJJu1D8/Ww3FsO42TMFrNr2/cmqwuUZ0a0uxrpkNYrsGjkEu7a+9MheyTzcm vyU2knz5/stkTN2LKz5REqOe24oRnypjpAfaoxRYXs+F8wml519InWlwCra49IUSxD1hXPxO WBe5lqcozu9LpNDH/brVSzHCSb7vjNGvvSVESDuoiHK8gNlf0v+epy5WYd7CGAgODPvDShGN g3eXuA== Organization: Red Hat In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 06.08.25 14:18, Pankaj Raghav (Samsung) wrote: >> We could go one step further and special case in mm_get_huge_zero_folio() + >> mm_put_huge_zero_folio() on CONFIG_STATIC_HUGE_ZERO_FOLIO. >> > > Hmm, but we could have also failed to allocate even though the option > was enabled. Then we return huge_zero_folio, which is NULL? Or what are you concerned about? -- Cheers, David / dhildenb