From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 0077716DEAE for ; Thu, 11 Jul 2024 18:56:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720724189; cv=none; b=AW7/inCEVWPwdLA0HZ6X9M/lxlQDbbkY8sjTuHcvn4Rp19QKedIjn/0qrVYNlr2WChFHXuFQL4P6IyIMObbu3fyVRhu3H566Inr2iL9d/zJC1r7V+742hqmHdGz6MAzaAdyPK41BGitykJt5X2LJNf7OW3XTzS5GE2GjY9xUGGM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720724189; c=relaxed/simple; bh=BvzN/zrI1Lg3aYVeeaVXdZJS1wjmXQPsNWjPosdonw8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=K+sZGiHMNTOCA4VNJRaypVeJUrm4keMSc240eBr/NCdy+jsa/p+cGcb+mSo7sKLDsCmtXI28hJdl6pFoAFcqzHsek/c6WLHvgJyUSlkPtQd4JcwFvn9K7Cbk4OMUWDQEail7WRLfVYhAPXH1tdB1SMUmg1k0L3XCfkfe20hc7ts= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none 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=Sjl+/RW7; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none 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="Sjl+/RW7" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1720724187; 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=8h7F4MlqrWHgk+nNfd6Cl6q2WvAakceBMWnBSEiYFJk=; b=Sjl+/RW7yl96FM7AlXAl01wUmIOWkXeRPTNP+zei/FirWR20DUNsqZEJCAdWxPtsqbxlZz LS5sUqPjfZlrKooRbc3/7yX2i8PaDp+cXFiA9cl3jiVRC7tExQzMzHDmnMsRICTNWuXCNU 4luHl3ABUI/McS+v+N4kXhH2Rhee+xc= Received: from mail-pj1-f72.google.com (mail-pj1-f72.google.com [209.85.216.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-694-pCW68TYVNt2zOKvuGZHssQ-1; Thu, 11 Jul 2024 14:56:24 -0400 X-MC-Unique: pCW68TYVNt2zOKvuGZHssQ-1 Received: by mail-pj1-f72.google.com with SMTP id 98e67ed59e1d1-2c974ec599cso901307a91.1 for ; Thu, 11 Jul 2024 11:56:24 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1720724183; x=1721328983; 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=8h7F4MlqrWHgk+nNfd6Cl6q2WvAakceBMWnBSEiYFJk=; b=t5vY60dAeHKFTvAaWxXzMiO6ae30kLu++1XLv/2SasulcqavC6PiM4PTO69RK9dRCk m+xojEfa/wByfKprRZpVuZcVU6rVCVnUhNavZTWuFDi9s93xHbcMQRl3ESU6jAhsCD61 gipgEtb7Oy4jXxQkXcSdDPG3j52B8MotrWFApYcRZwa8II9hBdxSdKYBc8WYm5780vdP TQ5oB4hLNP0kmCxaaR06uTyxC5jYsrUP3oeZnL9mnj1ajcVN8K1Bl0UXzGLnQf0lwak8 oNb1HgmOft44fmTkpTAQ9xfSwG2Ra9HVFlDznkApuCpmcjGHAO1nKgOrrdrCEPsFuw/8 AGdw== X-Forwarded-Encrypted: i=1; AJvYcCXoMFsceDuv1AKPnuYLpirWaLz7ppbzeSDIvi49xX5o4u0w/lecznLHEqLwUzRWr75Q5mQFqMzMHcCxoAalGQeeIlpafXoAniYw X-Gm-Message-State: AOJu0YzRH8jSxkrUUQR+MCdLog3RLd7BJXkH78TLlQ4fK89Rkmj4N5aU kwFtiR2SIwndSjM1/dPYejiZcSZBu3pyGjguUFy/UtvYxea+xXURsqm0E4ikCVBqw6jb8yTLi8n rNjQh2ZBfldNRcqDoKfQ263OQJmr3Lq0Rqg8EfZNfGNC9bCulpbPtLMRTnQ== X-Received: by 2002:a17:90a:e648:b0:2c8:f3b5:7dd1 with SMTP id 98e67ed59e1d1-2cac6e3ede4mr664297a91.16.1720724183524; Thu, 11 Jul 2024 11:56:23 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGCeGooxyB497nu/OI0/YZImP0In9UtmI/QnPSNNDvRuaucq4SMLS65EYW8tw2xfvfuPAj8dQ== X-Received: by 2002:a17:90a:e648:b0:2c8:f3b5:7dd1 with SMTP id 98e67ed59e1d1-2cac6e3ede4mr664261a91.16.1720724183031; Thu, 11 Jul 2024 11:56:23 -0700 (PDT) Received: from [10.35.209.243] ([208.115.86.77]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-2c99a950c37sm14149003a91.13.2024.07.11.11.56.21 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 11 Jul 2024 11:56:22 -0700 (PDT) Message-ID: <443146f4-9db8-4a19-91f1-b6822fad8ce8@redhat.com> Date: Thu, 11 Jul 2024 20:56:21 +0200 Precedence: bulk X-Mailing-List: linux-api@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v22 1/4] mm: add MAP_DROPPABLE for designating always lazily freeable mappings To: "Jason A. Donenfeld" Cc: Linus Torvalds , linux-kernel@vger.kernel.org, patches@lists.linux.dev, tglx@linutronix.de, linux-crypto@vger.kernel.org, linux-api@vger.kernel.org, x86@kernel.org, Greg Kroah-Hartman , Adhemerval Zanella Netto , Carlos O'Donell , Florian Weimer , Arnd Bergmann , Jann Horn , Christian Brauner , David Hildenbrand , linux-mm@kvack.org References: <98798483-dfcd-451e-94bb-57d830bf68d8@redhat.com> <54b6de32-f127-4928-9f4a-acb8653e5c81@redhat.com> <8586b19c-2e14-4164-888f-8c3b86f3f963@redhat.com> 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/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: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 11.07.24 20:54, Jason A. Donenfeld wrote: > On Thu, Jul 11, 2024 at 08:24:07PM +0200, David Hildenbrand wrote: >>> And PG_large_rmappable seems to only be used for hugetlb branches. >> >> It should be set for THP/large folios. > > And it's tested too, apparently. > > Okay, well, how disappointing is this below? Because I'm running out of > tricks for flag reuse. > > diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h > index b9e914e1face..c1ea49a7f198 100644 > --- a/include/linux/page-flags.h > +++ b/include/linux/page-flags.h > @@ -110,6 +110,7 @@ enum pageflags { > PG_workingset, > PG_error, > PG_owner_priv_1, /* Owner use. If pagecache, fs may use*/ > + PG_owner_priv_2, Oh no, no new page flags please :) Maybe just follow what Linux suggested: pass vma to pte_dirty() and always return false for these special VMAs. -- Cheers, David / dhildenb