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 X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3FF81C433DF for ; Tue, 2 Jun 2020 14:16:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 270F4207F9 for ; Tue, 2 Jun 2020 14:16:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728224AbgFBOQM (ORCPT ); Tue, 2 Jun 2020 10:16:12 -0400 Received: from mx2.suse.de ([195.135.220.15]:43040 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728140AbgFBOQL (ORCPT ); Tue, 2 Jun 2020 10:16:11 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id B78A7AC53; Tue, 2 Jun 2020 14:16:12 +0000 (UTC) From: Vlastimil Babka To: Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@android.com, vinmenon@codeaurora.org, Kees Cook , Matthew Garrett , Vlastimil Babka , Jann Horn , Vijayanand Jitta Subject: [RFC PATCH 0/5] replace runtime slub_debug toggling with more capable boot parameter Date: Tue, 2 Jun 2020 16:15:14 +0200 Message-Id: <20200602141519.7099-1-vbabka@suse.cz> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, we had recently reports [1,2] of troubles with runtime writes to various SLUB per-cache sysfs files related to slub_debug or tuning leading to crashes. I have inspected all those writable files and the rather unfortunate result is that most of them are made read-only by this patchset, as fixing the issues doesn't seem viable. Details for each are given in each patch. I expect some resistance, hence the RFC. The runtime toggles were however necessary for the use case described in [3], so the first patch extends the slub_debug boot parameter syntax to achieve the same configuration without runtime toggles. That should hopefully make the changes more feasible. [1] https://lkml.kernel.org/r/1580379523-32272-1-git-send-email-vjitta@codeaurora.org [2] https://lore.kernel.org/r/CAG48ez31PP--h6_FzVyfJ4H86QYczAFPdxtJHUEEan+7VJETAQ@mail.gmail.com [3] https://lore.kernel.org/r/1383cd32-1ddc-4dac-b5f8-9c42282fa81c@codeaurora.org Vlastimil Babka (5): mm, slub: extend slub_debug syntax for multiple blocks mm, slub: make some slub_debug related attributes read-only mm, slub: remove runtime allocation order changes mm, slub: make remaining slub_debug related attributes read-only mm, slub: make reclaim_account attribute read-only .../admin-guide/kernel-parameters.txt | 2 +- Documentation/vm/slub.rst | 36 +- mm/slub.c | 315 ++++++++---------- 3 files changed, 163 insertions(+), 190 deletions(-) -- 2.26.2