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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 B9565C3F2D1 for ; Tue, 3 Mar 2020 17:55:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8F58220728 for ; Tue, 3 Mar 2020 17:55:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="gDBM/cKD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732665AbgCCRzL (ORCPT ); Tue, 3 Mar 2020 12:55:11 -0500 Received: from mail-il1-f194.google.com ([209.85.166.194]:39906 "EHLO mail-il1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732645AbgCCRzH (ORCPT ); Tue, 3 Mar 2020 12:55:07 -0500 Received: by mail-il1-f194.google.com with SMTP id w69so3550949ilk.6 for ; Tue, 03 Mar 2020 09:55:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=ayIxKKAwCnNFCQ+lZzklsRs5rXYB11mGFHyYGI5wUqQ=; b=gDBM/cKDaAMh9NyfxfoObozsG9BZGD80+G1UGm/xV8TRxMqdcxd3lkS7Tjc2EZIK5k O23wx5QTaZLVh2TUQMR/TRMtGrzlj3bIrack/HPTGO10ixgYa7tKMJ096FUlVlKSpVlk 4T4h8gnuTVFX1A/hBPx1SunMMPdgrCbXi4uVHq95icV0U4T5UQyhYuUIg4plkkEWhLtK iY/tQv5MsboKHbHaXcPeN6P1iYXGkLhHrJcXbFJGYOaBrXt/zh7Z9xLjhLQSofkYiJbd L7hD+kdiIc4k3EkxMC+O1Z2XYNe5g1WwxJxZxyKY6/WHpQcxhJwpXpYZ9S8bMjc/4KH3 aUmw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=ayIxKKAwCnNFCQ+lZzklsRs5rXYB11mGFHyYGI5wUqQ=; b=VsXf3hSeLNPd0Jr7nkPEBN11iMpwXKRmdnCLD6K9XO5iQ0mlLkYqMnaeXBW68gIjjy A4Z8rLYTyqpi6V250M2u0TZI0oD3qVpKskADsgppU+i+dBQxeahjsZ0rrGn9aPjLCtgD VZ9qXbb73PKZr93mtjzisnmsLEm6YRSDzC2KpbLqfd7dW+A+pa/OX+kPr7M7qbD7eJBd aGpkkth/NxlX+yhEdxqHRO+cWBKX18NYIwI4wIDn4WsDNautfxXPuV6y+9TG0h4p6r8z 4iRzVJ3pJauukjX9NKQ8AzqmaFFp784lQ2IbivOjyzc2O7BAqFOefulgvVEH8EWHdeql vDcg== X-Gm-Message-State: ANhLgQ0Geu+08JTZmS8fASmEVYVM97jXEoHYXZyCf+2bLTQ8gllHxBvS web7fp/EkNX9Jlv1DY1M/9RuLw== X-Google-Smtp-Source: ADFU+vswN1+JEsE23FDapwuSVGGnBVQIgUF2nTXa5raP7vGWLMOlfTYLzjaimZzTkgwmW/1PXcHyyw== X-Received: by 2002:a92:8f46:: with SMTP id j67mr5772317ild.125.1583258106150; Tue, 03 Mar 2020 09:55:06 -0800 (PST) Received: from [192.168.1.159] ([65.144.74.34]) by smtp.gmail.com with ESMTPSA id h14sm1061362iow.23.2020.03.03.09.55.05 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 03 Mar 2020 09:55:05 -0800 (PST) Subject: Re: [PATCH 5.4 062/152] bcache: ignore pending signals when creating gc and allocator thread To: Greg Kroah-Hartman , linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org, Coly Li , Sasha Levin References: <20200303174302.523080016@linuxfoundation.org> <20200303174309.501274295@linuxfoundation.org> From: Jens Axboe Message-ID: Date: Tue, 3 Mar 2020 10:55:04 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200303174309.501274295@linuxfoundation.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/3/20 10:42 AM, Greg Kroah-Hartman wrote: > From: Coly Li > > [ Upstream commit 0b96da639a4874311e9b5156405f69ef9fc3bef8 ] > > When run a cache set, all the bcache btree node of this cache set will > be checked by bch_btree_check(). If the bcache btree is very large, > iterating all the btree nodes will occupy too much system memory and > the bcache registering process might be selected and killed by system > OOM killer. kthread_run() will fail if current process has pending > signal, therefore the kthread creating in run_cache_set() for gc and > allocator kernel threads are very probably failed for a very large > bcache btree. > > Indeed such OOM is safe and the registering process will exit after > the registration done. Therefore this patch flushes pending signals > during the cache set start up, specificly in bch_cache_allocator_start() > and bch_gc_thread_start(), to make sure run_cache_set() won't fail for > large cahced data set. Please drop this one, it's being reverted in mainline. -- Jens Axboe