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=-11.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 E34B3C432BE for ; Tue, 31 Aug 2021 23:02:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B993060232 for ; Tue, 31 Aug 2021 23:02:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241026AbhHaXDL (ORCPT ); Tue, 31 Aug 2021 19:03:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42900 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235659AbhHaXDK (ORCPT ); Tue, 31 Aug 2021 19:03:10 -0400 Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E9BACC061575 for ; Tue, 31 Aug 2021 16:02:14 -0700 (PDT) Received: by mail-pj1-x102a.google.com with SMTP id n13-20020a17090a4e0d00b0017946980d8dso3222316pjh.5 for ; Tue, 31 Aug 2021 16:02:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=6fVAWuXyMT/0QgdpRVgsjl6TJ333S1dL0H95dr0w7D4=; b=cN/pRkWepY9szJhCGFEPduR7G2SfRnHtedWRZGHZgo7ynsiU42WzlO23dLKzbB5Cxm UfhXiclsdLL1nN6w2+HaQ5elSEGTMTMDi3zRaDVHaE51R0tY4B8WvTHgpz65Rey73xXt X1C0nLlMydp9kyQbDpJSA4faH41L5bAJf5msA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=6fVAWuXyMT/0QgdpRVgsjl6TJ333S1dL0H95dr0w7D4=; b=FxTYK/29YuMZAx8syWFx4XjtVtGXWiP5q+WAbXrSGS8uqHddE77Uof7KXbhZtGQ5pv wUWIevMTwKY2ETDc4No4v5Hyj0ltqNvuxkVb9AWftc/SWPgzPa95h+gs8EynrYzGNzDU Mw2RiGVoxDfx/lor7h6+imBIDvPHJ1NYSnSPMuXwdSSUuUei6I9RWd2Bq99dxIFBGQJk eDD+gASpM19Dc+TgNX6AxGHVfuaH5AgEokeA8YR/39z/YVEjdU8kyVDbV3fJ7hcUrQ3u 9QUZ+wnKSonsxcbIeJwgWiJlg1/yMvGQBM8czvgD/InkQv/imLTFDC5Gb+Wk0k2zItA6 KNqw== X-Gm-Message-State: AOAM531+WEmJTQX8uFjMHs3qZ8telJZMA2c0feSDr2VUeiZ6wexTYdNX 2Ft1m94NEI/ZenHF654rnF1/yA== X-Google-Smtp-Source: ABdhPJzE6cWm5HiRuXg08jWq8VHUKGkg1rU7QEpW+TjtjSxhB6ZOgXMAWsvktwi9zY3Ybfadh7SHng== X-Received: by 2002:a17:902:c401:b0:138:e450:1ec4 with SMTP id k1-20020a170902c40100b00138e4501ec4mr6798556plk.56.1630450934463; Tue, 31 Aug 2021 16:02:14 -0700 (PDT) Received: from google.com ([2409:10:2e40:5100:6d52:87b8:b55b:8800]) by smtp.gmail.com with ESMTPSA id f18sm8511663pfc.161.2021.08.31.16.02.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 31 Aug 2021 16:02:13 -0700 (PDT) Date: Wed, 1 Sep 2021 08:02:09 +0900 From: Sergey Senozhatsky To: Petr Mladek Cc: =?utf-8?B?7J207Jqp7YOd?= , "senozhatsky@chromium.org" , "rostedt@goodmis.org" , "john.ogness@linutronix.de" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] printk: use kvmalloc instead of kmalloc for devkmsg_user Message-ID: References: <20210830071701epcms1p70f72ae10940bc407a3c33746d20da771@epcms1p7> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (21/08/31 14:42), Petr Mladek wrote: > On Mon 2021-08-30 16:17:01, 이용택 wrote: > > Size of struct devkmsg_user increased to 16784 by commit 896fbe20b4e2 > > ("printk: use the lockless ringbuffer") so order3(32kb) is needed for > > kmalloc. Under stress conditions the kernel may temporary fail to > > allocate 32k with kmalloc. Use kvmalloc instead of kmalloc to aviod > > this issue. > > > > qseecomd invoked oom-killer: gfp_mask=0x40cc0(GFP_KERNEL|__GFP_COMP), order=3, oom_score_adj=-1000 > > Call trace: > > dump_backtrace+0x0/0x34c > > dump_stack_lvl+0xd4/0x16c > > dump_header+0x5c/0x338 > > out_of_memory+0x374/0x4cc > > __alloc_pages_slowpath+0xbc8/0x1130 > > __alloc_pages_nodemask+0x170/0x1b0 > > kmalloc_order+0x5c/0x24c > > devkmsg_open+0x1f4/0x558 > > memory_open+0x94/0xf0 > > chrdev_open+0x288/0x3dc > > do_dentry_open+0x2b4/0x618 > > path_openat+0xce4/0xfa8 > > do_filp_open+0xb0/0x164 > > do_sys_openat2+0xa8/0x264 > > __arm64_sys_openat+0x70/0xa0 > > el0_svc_common+0xc4/0x270 > > el0_svc+0x34/0x9c > > el0_sync_handler+0x88/0xf0 > > el0_sync+0x1bc/0x200 > > > > DMA32: 4521*4kB (UMEC) 1377*8kB (UMECH) 73*16kB (UM) 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 30268kB > > Normal: 2490*4kB (UMEH) 277*8kB (UMH) 27*16kB (UH) 1*32kB (H) 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 12640kB > > > > Signed-off-by: Yong-Taek Lee > > Reviewed-by: Petr Mladek Acked-by: Sergey Senozhatsky