From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A5CDE31716D for ; Tue, 24 Mar 2026 20:13:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774383183; cv=none; b=ZfBMMTsQ4p66Qv0BC3NFMQAwDnBYilaZpLAbpm+P7HyEeP3XIfPZINrQBkBLskUh/2PfZMRcgYloyXqVLGUF30koW6j61UZyGkGmuyizDEtyu8KHdWE3Ctwe09akL74la7vq2FpV/ceOXPDNWQq1y+CP/0ilVu4doJUtSTpGBYI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774383183; c=relaxed/simple; bh=Ntqkf0j8AhQ1QfbmlWiRJGsbUyfajr+sdoox1lR0fqE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=iZ4PEgbESJQm5K1Q0FCKAr8EQ6Z/v+I18/DZ48/dMyGw7ViSfZPcNhesB98n06xhaOi9R+J53VPq5mw1Mc5CmT32L8fWOoqCTuIa8M+ZegE6EfpF0SI5P1YEhozXhuxa2eo2fiVld9nlH9/nnIdcyJSqrIZDIAY2IVE9XupPQvI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=f4hSFRzm; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="f4hSFRzm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 68964C2BC9E; Tue, 24 Mar 2026 20:13:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774383183; bh=Ntqkf0j8AhQ1QfbmlWiRJGsbUyfajr+sdoox1lR0fqE=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=f4hSFRzmOajxJBAfaNPOWzCVUDlIjeYpWV6tIqLeyaiUd+I5UHC8KBJ4Bfqomwk30 18rXLexSoCDcXcyMAAeyjEnTQiiYHbbuJydZGfccJqZ6xS5ID8JVC2eivG5aP4Kc/d +jmx3QDKkRmNEUDol3c0YFdvpjQD8+Mst3Wz+i+Ti1X44+CHI0I3JCa0WbVXr/tI/g 2sFr5SSjzclH0tgWNOK7i+NpQh4lmyAB+zv0To4r/Xs/wAZQAGpBinJXYLS+xWCR+B DgX0X6B/JLpx8Z/GKk6nbhUjIzXdy6qiQ7e77LO9Tor/2FM8IyqmqK1IGxRBNl1aDV 4k4eI8OI0pmIQ== Message-ID: Date: Tue, 24 Mar 2026 21:12:57 +0100 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 v2 1/2] mm/mprotect: move softleaf code out of the main function To: Pedro Falcato , Andrew Morton , "Liam R. Howlett" , Lorenzo Stoakes Cc: Vlastimil Babka , Jann Horn , Dev Jain , Luke Yang , jhladky@redhat.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260324154342.156640-1-pfalcato@suse.de> <20260324154342.156640-2-pfalcato@suse.de> 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: <20260324154342.156640-2-pfalcato@suse.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/24/26 16:43, Pedro Falcato wrote: > Move softleaf change_pte_range code into a separate function. This makes > the change_pte_range() function a good bit smaller, and lessens cognitive > load when reading through the function. > > Reviewed-by: Lorenzo Stoakes (Oracle) > Signed-off-by: Pedro Falcato > --- > mm/mprotect.c | 129 +++++++++++++++++++++++++++----------------------- > 1 file changed, 69 insertions(+), 60 deletions(-) > > diff --git a/mm/mprotect.c b/mm/mprotect.c > index 9681f055b9fc..2eaf862e5734 100644 > --- a/mm/mprotect.c > +++ b/mm/mprotect.c > @@ -211,6 +211,74 @@ static void set_write_prot_commit_flush_ptes(struct vm_area_struct *vma, > commit_anon_folio_batch(vma, folio, page, addr, ptep, oldpte, ptent, nr_ptes, tlb); > } > > +static long change_softleaf_pte(struct vm_area_struct *vma, > + unsigned long addr, pte_t *pte, pte_t oldpte, unsigned long cp_flags) > +{ > + const bool uffd_wp = cp_flags & MM_CP_UFFD_WP; > + const bool uffd_wp_resolve = cp_flags & MM_CP_UFFD_WP_RESOLVE; > + softleaf_t entry = softleaf_from_pte(oldpte); > + pte_t newpte; > + > + if (softleaf_is_migration_write(entry)) { > + const struct folio *folio = softleaf_to_folio(entry); > + > + /* > + * A protection check is difficult so > + * just be safe and disable write > + */ > + if (folio_test_anon(folio)) > + entry = make_readable_exclusive_migration_entry( > + swp_offset(entry)); We can now even fit this into a single line without feeling bad :) > + else > + entry = make_readable_migration_entry(swp_offset(entry)); > + newpte = swp_entry_to_pte(entry); > + if (pte_swp_soft_dirty(oldpte)) > + newpte = pte_swp_mksoft_dirty(newpte); > + } else if (softleaf_is_device_private_write(entry)) { > + /* > + * We do not preserve soft-dirtiness. See > + * copy_nonpresent_pte() for explanation. > + */ > + entry = make_readable_device_private_entry( > + swp_offset(entry)); Same here. > + newpte = swp_entry_to_pte(entry); > + if (pte_swp_uffd_wp(oldpte)) > + newpte = pte_swp_mkuffd_wp(newpte); > + } else if (softleaf_is_marker(entry)) { > + /* Acked-by: David Hildenbrand (Arm) -- Cheers, David