From patchwork Tue Jun 2 14:15:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vlastimil Babka X-Patchwork-Id: 11583927 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C93D1912 for ; Tue, 2 Jun 2020 14:16:14 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9681F20870 for ; Tue, 2 Jun 2020 14:16:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9681F20870 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C084C280003; Tue, 2 Jun 2020 10:16:13 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id BB7DB80010; Tue, 2 Jun 2020 10:16:13 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id ACD2A280003; Tue, 2 Jun 2020 10:16:13 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0224.hostedemail.com [216.40.44.224]) by kanga.kvack.org (Postfix) with ESMTP id 91FB980010 for ; Tue, 2 Jun 2020 10:16:13 -0400 (EDT) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 3477C18048251 for ; Tue, 2 Jun 2020 14:16:13 +0000 (UTC) X-FDA: 76884471426.08.base18_3639421353e26 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin08.hostedemail.com (Postfix) with ESMTP id 08E161800997A for ; Tue, 2 Jun 2020 14:16:13 +0000 (UTC) X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,vbabka@suse.cz,,RULES_HIT:30054:30074,0,RBL:195.135.220.15:@suse.cz:.lbl8.mailshell.net-62.2.6.2 64.100.201.201,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:17,LUA_SUMMARY:none X-HE-Tag: base18_3639421353e26 X-Filterd-Recvd-Size: 2677 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf22.hostedemail.com (Postfix) with ESMTP for ; Tue, 2 Jun 2020 14:16:12 +0000 (UTC) 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 X-Rspamd-Queue-Id: 08E161800997A X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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(-)