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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E77E7CA5FA3 for ; Mon, 28 Sep 2026 18:58:50 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9F58B6B0088; Mon, 28 Sep 2026 14:58:49 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9A6406B008A; Mon, 28 Sep 2026 14:58:49 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8963B6B008C; Mon, 28 Sep 2026 14:58:49 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 5C67D6B0088 for ; Mon, 28 Sep 2026 14:58:49 -0400 (EDT) Received: from smtpin17.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay09.hostedemail.com (Postfix) with ESMTP id CBAB18030A for ; Mon, 28 Sep 2026 18:58:48 +0000 (UTC) X-FDA: 85264082736.17.E593E02 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf27.hostedemail.com (Postfix) with ESMTP id 07F8440004 for ; Mon, 28 Sep 2026 18:58:46 +0000 (UTC) Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=nOYYg7oC; spf=pass (imf27.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1790621927; h=from:from:sender: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:dkim-signature; bh=BQJlLat4qxj8pgDrowtyIAkoQQPKp9J5TEk8suVVKjQ=; b=4QBtYPH+FOVRdxUHBW6Ii+eyiVXz+Ud/PRiFDz+CEwo+Xv6rgL8vN8V1B3FQ9n1jowGC0B 4zASvqUHX26g1tvHY/ntLStOCNdTTw1sQNHLmbkNSPabElBfI+f2cBnzCBMBUz13HOMtp9 36ceXurGEp+MrM1LsF8N8vk1uRQbIn0= ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=nOYYg7oC; spf=pass (imf27.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1790621927; b=KLh+AteLM/4xUkjdx4RXbkX7ONbnxl6dYyLibNA+R2Qvb2SRw/VlRplFiGsJ+4pA3qi3bv V/HdDEcyakqFm3ODXUJWSzkw1h5l2G362AKScN9CNuqLZuyuFqa51db4pUlHfx4Xo1R7bQ mdD+heO6Xeon2/JP4iOz69jo6PBjZ4I= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 037B941905; Mon, 28 Sep 2026 18:58:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EE8331F000FF; Mon, 28 Sep 2026 18:58:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790621925; bh=BQJlLat4qxj8pgDrowtyIAkoQQPKp9J5TEk8suVVKjQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=nOYYg7oCN+CEi6+HSLYl5pLYDPIkgl9oIzaKeRsIwnLQLz8gmq2Wlu8L8C67dnJeG 8Jqjug8DQ2jWcrnxQaDVIw6DTaQKfwBEz5XUeHMtQu+4oXvZNYq/hQmhg9GTUYuIaX BDacpyX/6tMbFS4fZj3+80NIoy+Z1ibgbEcH6aPXMhaAGIYuRy/vAvhAZDbjQBVPe9 7bwsvipBELhLtcU85W+9CT0n5D9xfPhyUfHWMBbm0bGZocbd8ObHRV61EiYsQnAK5O OCs1pBsYyjVxK8UZ3AoZWY14OtJ41S0GCn9WpAN4rU+kY6M4c63VqlKaID+AO+oIJZ sntZfdjPV6lGA== Message-ID: <9d4517d0-0e78-4eee-970e-0cac9d0a856f@kernel.org> Date: Mon, 28 Sep 2026 20:58:22 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 00/12] CRASH_MEMACTION: describe pages to a kdump kernel (was: CRASH_WIPE_SECRETS) To: "Lorenzo Stoakes (ARM)" , =?UTF-8?Q?Jan_Sebastian_G=C3=B6tte?= Cc: Jonathan Corbet , Shuah Khan , Randy Dunlap , Rob Herring , Saravana Kannan , Andrew Morton , Baoquan He , Mike Rapoport , Pasha Tatashin , Pratyush Yadav , Dave Young , Greg Kroah-Hartman , "Rafael J. Wysocki" , Danilo Krummrich , Muchun Song , Oscar Salvador , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Zi Yan , Catalin Marinas , Will Deacon , Mark Rutland , Alasdair Kergon , Mike Snitzer , Mikulas Patocka , Benjamin Marzinski , Herbert Xu , "David S. Miller" , Mimi Zohar , David Howells , Jarkko Sakkinen , Paul Moore , James Morris , "Serge E. Hallyn" , James Bottomley , "Liam R. Howlett" , Jann Horn , Pedro Falcato , Rik van Riel , Harry Yoo , Lance Yang , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Usama Arif , Kiryl Shutsemau , Matthew Brost , Joshua Hahn , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Peter Xu , Arnd Bergmann , Eric Biggers , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, kexec@lists.infradead.org, driver-core@lists.linux.dev, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, dm-devel@lists.linux.dev, linux-crypto@vger.kernel.org, linux-integrity@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org References: <20260928-crash-memaction-upstream-20260921-v3-0-e511e9ee2329@jaseg.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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 07F8440004 X-Rspam-User: X-Stat-Signature: r14oqgsg6n993it7b4axzi679g31mzbq X-HE-Tag: 1790621926-929621 X-HE-Meta: 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 YqH4K+yd TVmkmP0WeFiT34p16mGDjzcRw+7tC75jRwBsVJAAfL228rDvMHAp2zt33eTDScOHppEqPPDLdaaSVY4SYCZHxXFE/owF8ukp24ptOfYZfo+GQUhVH1kuHl2VFJI93uH1HWTuZG84Ws06uQitXPPwicUJffDNA8PbN+nyZCqEubRMTUV88/eRsKk20yTf1wTz5Cjby8vlYivVrekgRWHyufYPrASAFMCgWoAfiIW/qsB0fBHyXEn6vv1a/DiKEgS2f2V+W4fFgUGvYbkldESmy68ga4BQMoVivFIeWMaW9ACBR3vXrRrKswL/PFDghkwMZtYrDWR31lO1HPFV6rzjgx+z8BfeZGGeYUuHSqw3+QI90kHlQm45A/Xyg8ZHtx7jFPYSBXBh3XPXGBTS6XSWd7NiMgg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 9/28/26 19:49, Lorenzo Stoakes (ARM) wrote: > On Mon, Sep 28, 2026 at 07:17:48PM +0200, Jan Sebastian Götte wrote: >> I'm using linux on an embedded target in a Hardware Security Module-like >> application. One requirement is that I want the system to be able to >> quickly erase its memory when it detects physical tampering. I'm >> approaching that by using kdump to load into a small payload that >> instead of dumping RAM, erases RAM frmo start to end. However, writing >> all of RAM, especially on an embedded target, is rather slow. For this >> reason, I propose a new crash_memaction mechanism that lets the old >> kernel indicate marked memory areas to the kdump kernel at page >> granularity. > > Sorry this all seems really invasive for what seems to be a very specific > use case. > > In general, with big changes like this, you should send the series as an > RFC. > > Please send any future revisions of this as an RFC. > > The bar for a new VMA flag, a new madvise() flag, It's actually three new madvise modes. Way to invasive indeed. This won't fly. -- Cheers, David