From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 38A554A2063; Thu, 10 Sep 2026 15:11:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789053116; cv=none; b=ADVP9xvJeOLPAqpc8bpeI16pdLtxGBy0OtHl75zzF25t+E5RTuYgkocLOKb4+WY7wn9kclp9atlzR72URrtpc6lCcUaqY5RC7K931ig1DRwFUxpDVFvRVb+JpEFgM5XOdi6kJRoxHi/jsvqnQbRmJcVKzayBpGH+uBdR//O0kN0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789053116; c=relaxed/simple; bh=9Yc48dfVmE/Rzkfkuz3UPe+YqnEyjcO1mePRgHC5Uss=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=PX9Fo3RIzrCIAQozxwyyREdr6NdPaLk1zVVmitiQpWMBlAyQlr96PPBdIkBBcShLvKfgZ5g5NmCD5iH4jB4GoF5R/d9UaBLjJkP8usFqe0GhYSPaT23+Di/G9PdCR6/vG+bWP3Z3XuPeWxNBEd3UsKecLSblZ6kaAI5OMXiIM2I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VO7pExAE; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VO7pExAE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 080341F000FF; Thu, 10 Sep 2026 15:11:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789053109; bh=m8oPxLNbD63jwykdDjogfzHJQI7uOPBa9BxKyoPjd+4=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=VO7pExAE9tLKDaKHb8xxcgxhPCuKZtJ6zqhDrvjdmuD5ErR0dFWQ+W4yXO85uiR/G VLfy0Ms/MhbB4PHPzIjKj2tKCdJUX6RZH/qbmjZ0B91Cfmt+JfqDDXa/L1WnPOVqei fV9VKnEzVUX8aeK75ayqlZuQesHZecS7vI38Dj+y9hTwqI1bAFZyxeLDSjUm4h5pen YEIZHAS2N3LiejXO8NXe1I4V5AI7I+lTbFRaWxg4MsaN/aGjuOhMu2T7i6T8pFD/8I GbYXY08QYFSc1G6dx1AmcjR+4rPenkEG973Xr8FBUtvk3WCo/B9Now/Ghs6ZlWDuoU AnTw3vabHbp1Q== Message-ID: Date: Thu, 10 Sep 2026 17:11:36 +0200 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 09/12] mm/sparse: remove SECTION_MARKED_PRESENT To: "Lorenzo Stoakes (ARM)" Cc: Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Kairui Song , Qi Zheng , Shakeel Butt , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Baoquan He , Baolin Wang , Brendan Jackman , Johannes Weiner , Zi Yan , Oscar Salvador , Greg Kroah-Hartman , "Rafael J. Wysocki" , Danilo Krummrich , Jan Kiszka , Kieran Bingham , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-cxl@vger.kernel.org, driver-core@lists.linux.dev, linux-fsdevel@vger.kernel.org, Seongjun Hong References: <20260909-b4-sparsemem_cleanups-v1-0-008fc8d579fe@kernel.org> <20260909-b4-sparsemem_cleanups-v1-9-008fc8d579fe@kernel.org> 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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/10/26 16:32, Lorenzo Stoakes (ARM) wrote: > On Wed, Sep 09, 2026 at 03:33:02PM +0200, David Hildenbrand (Arm) wrote: >> All present section iterators run before memory hotplug added any >> further memory sections, Therefore, we can simply use the SECTION_IS_EARLY >> flag by setting that flag earlier in sparse_prepare_early_sections(). > > Hmm? sparse_prepare_early_sections() doesn't seem to be a function that exists? > > Do you mean sparse_sections_init()? Rebase artifact, thanks! :) > >> >> Get rid of SECTION_MARKED_PRESENT entirely and rename >> for_each_present_section_nr() to for_each_early_section_nr(). >> >> Also update the gdb script to use the updated value for >> SECTION_IS_EARLY. > > The change seems fine. > >> >> No functional change intended. >> >> Signed-off-by: David Hildenbrand (Arm) > > With commit msg updated: > > Acked-by: Lorenzo Stoakes (ARM) > > One small question type comment below. Thanks! [...] >> +++ b/scripts/gdb/linux/mm.py >> @@ -76,7 +76,7 @@ class x86_page_ops(): >> self.SECTION_IS_EARLY = 1 << int(gdb.parse_and_eval('SECTION_IS_EARLY_BIT')) >> except: >> self.SECTION_HAS_MEM_MAP = 1 << 0 >> - self.SECTION_IS_EARLY = 1 << 3 >> + self.SECTION_IS_EARLY = 1 << 2 > > Seems a bit strage given the code is: > > try: > self.SECTION_HAS_MEM_MAP = 1 << int(gdb.parse_and_eval('SECTION_HAS_MEM_MAP_BIT')) > self.SECTION_IS_EARLY = 1 << int(gdb.parse_and_eval('SECTION_IS_EARLY_BIT')) > except: > self.SECTION_HAS_MEM_MAP = 1 << 0 > self.SECTION_IS_EARLY = 1 << 2 > > Whereas other variables must be available with no try, e.g.: > > self.PAGE_OFFSET = int(gdb.parse_and_eval("page_offset_base")) > self.VMEMMAP_START = int(gdb.parse_and_eval("vmemmap_base")) > self.PHYS_BASE = int(gdb.parse_and_eval("(unsigned long) phys_base")) > > etc. > > Is there some weirdness with gdb? Or is it maybe because there are some configs > without these symbols maybe? TBH, I have absolutely no idea and I was asking myself the same thing (but decided that I couldn't care less about a python gdb script). This code was added in February: commit 55f8b4518d14b7436f70defe27faba4eca0cd4e1 Author: Seongjun Hong Date: Mon Feb 2 12:42:41 2026 +0900 scripts/gdb: implement x86_page_ops in mm.py Implement all member functions of x86_page_ops strictly following the logic of aarch64_page_ops. This includes full support for SPARSEMEM and standard page translation functions. This fixes compatibility with 'lx-' commands on x86_64, preventing AttributeErrors when using lx-pfn_to_page and others. @Seongjun, why are these conditional and the others not? Trying to support older kernels? -- Cheers, David