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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8E0B5C433F5 for ; Mon, 14 Feb 2022 03:07:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239885AbiBNDHL (ORCPT ); Sun, 13 Feb 2022 22:07:11 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:47682 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239895AbiBNDHJ (ORCPT ); Sun, 13 Feb 2022 22:07:09 -0500 Received: from mail-pf1-x430.google.com (mail-pf1-x430.google.com [IPv6:2607:f8b0:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 12FAE56222 for ; Sun, 13 Feb 2022 19:07:00 -0800 (PST) Received: by mail-pf1-x430.google.com with SMTP id m22so7671806pfk.6 for ; Sun, 13 Feb 2022 19:07:00 -0800 (PST) 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:in-reply-to; bh=L8f/dy++5LF1Z+wO72aS7wlC9x5EEx283gxkskdGuXo=; b=e+6som/Tb93dp4VvtBjU1FzkdQVoD+0eIVZwtosEgh8TYLLMBdCgj+aO55P0CKVNWT B4YcB2XQcP4fX9XxEd2bct830bQOSxRkR7+75wGXFB+UmhwOkogZ0O9DasgjG3ojfwc2 TSFNfI1uq130vnGsq3jeRQjkRbLiLqMOLExHQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=L8f/dy++5LF1Z+wO72aS7wlC9x5EEx283gxkskdGuXo=; b=aqbMRHRtXpknUovalt/vnlJAq9I8CcawCOnqTbowY4unJsn7XegeH35DCiuipxJIXA dJPrHKff2vrYx42e0GiC6DlWHUxsSJtYrX4lsLb+IS6QHaExmO5629IaUWnZ0r7E5wMB 1fHGiv4irPGviHQ+keftMes0QanKefKhw3zS6rhRCz95yuK6Jxd+tMX3H+DeRdUA5708 VTnTjfqjg+/VejYjqi3+PDpL097ALPgletZfNtW5ymFO57A4a5iIs8KrnGkov2trwZVI Wf6ZsTC5bvvciGdYvjDiNGCEeiihgMqgr6OW432IitkODbzLE2aGK8yD6YJZrnic8lBN nPkA== X-Gm-Message-State: AOAM530QDEw459ITqLdcQ7SkTbzruUbcgrV8xSrIMp5Y1YBVseARBqns dLuzxqi4CI/h0ASdROmFV85Brg== X-Google-Smtp-Source: ABdhPJx1H2Gc+HhUAhblBTUvmqTQaV9LtBNLCgdYi8Jt0ecEOsepVeCHLIh1ytP8jPXH0iKGwF9EYA== X-Received: by 2002:a63:6c43:: with SMTP id h64mr10114748pgc.72.1644808018860; Sun, 13 Feb 2022 19:06:58 -0800 (PST) Received: from google.com ([2401:fa00:8f:203:b736:df7d:23c5:206e]) by smtp.gmail.com with ESMTPSA id e8sm17571509pfv.168.2022.02.13.19.06.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 13 Feb 2022 19:06:58 -0800 (PST) Date: Mon, 14 Feb 2022 12:06:53 +0900 From: Sergey Senozhatsky To: Guanghui Feng Cc: pmladek@suse.com, senozhatsky@chromium.org, rostedt@goodmis.org, john.ogness@linutronix.de, keescook@chromium.org, anton@enomsg.org, ccross@android.com, tony.luck@intel.com, linux-kernel@vger.kernel.org, baolin.wang@linux.alibaba.com, yaohongbo@linux.alibaba.com, zhangliguang@linux.alibaba.com, zhuo.song@linux.alibaba.com Subject: Re: [PATCH] printk: fix softlockup/rcu stall warning without setting CONFIG_PREEMPTION Message-ID: References: <1644672462-20793-1-git-send-email-guanghuifeng@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1644672462-20793-1-git-send-email-guanghuifeng@linux.alibaba.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (22/02/12 21:27), Guanghui Feng wrote: > console_unlock+0x220/0x420 > vprintk_emit+0x17c/0x1ac > vprintk_default+0x3c/0x44 > vprintk+0x38/0x70 > printk+0x64/0x88 > dump_task.part.0+0xc4/0xe0 > dump_task+0x70/0x74 > dump_tasks+0x78/0x90 > dump_global_header+0xcc/0xe8 > oom_kill_process+0x258/0x274 > out_of_memory.part.0+0xb0/0x33c > out_of_memory+0x4c/0xa0 > __alloc_pages_may_oom+0x11c/0x1a0 > __alloc_pages_slowpath.constprop.0+0x4c0/0x75c > __alloc_pages_nodemask+0x2b4/0x310 > alloc_pages_current+0x8c/0x140 > get_zeroed_page+0x20/0x50 > __pud_alloc+0x40/0x190 > copy_pud_range+0x264/0x280 > copy_page_range+0xe8/0x204 > dup_mmap+0x334/0x434 > dup_mm+0x64/0x11c > copy_process+0x5e0/0x11a0 > kernel_clone+0x94/0x364 > __do_sys_clone+0x54/0x80 > __arm64_sys_clone+0x24/0x30 > el0_svc_common.constprop.0+0x7c/0x210 > do_el0_svc+0x74/0x90 > el0_svc+0x24/0x60 > el0_sync_handler+0xa8/0xb0 > el0_sync+0x140/0x180 [..] > @@ -2716,7 +2716,11 @@ void console_unlock(void) > if (handover) > return; > > +#ifndef CONFIG_PREEMPTION > + if (do_cond_resched || need_resched()) > +#else > if (do_cond_resched) > +#endif > cond_resched(); console_unlock() can be called from atomic context, it should not schedule when it cannot do so. That's what console_may_schedule indicates.