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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02A0FC433EF for ; Thu, 9 Dec 2021 07:52:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 59C896B0071; Thu, 9 Dec 2021 02:52:08 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 54C706B0073; Thu, 9 Dec 2021 02:52:08 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 43AFB6B0074; Thu, 9 Dec 2021 02:52:08 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0019.hostedemail.com [216.40.44.19]) by kanga.kvack.org (Postfix) with ESMTP id 33E9A6B0071 for ; Thu, 9 Dec 2021 02:52:08 -0500 (EST) Received: from smtpin19.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id DED3C1857D1D1 for ; Thu, 9 Dec 2021 07:51:57 +0000 (UTC) X-FDA: 78897487074.19.149C0A4 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by imf26.hostedemail.com (Postfix) with ESMTP id 592F6140002 for ; Thu, 9 Dec 2021 07:51:57 +0000 (UTC) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id DD9C6212BF; Thu, 9 Dec 2021 07:51:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1639036315; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=x/7/rcnJctjFhlP0Z/jKgO0KxVAnZ5tPslNFyeLkqJo=; b=XLMyk2a6AQ19NvR+UE/nfaizC0vafoipHNbhLdO3kyCYjpyAzHBmkFgPhNSdnsPJIDoB/P w0s+mUejR0couT27WARaEw+ii5ZU8FpKYpJNrh1fffVnYFw4XrYUJHbvRY09axSQSA7k0l 88uMOcMi/cUez75J21BM/QmEgF3EwjQ= Received: from suse.cz (unknown [10.100.201.86]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 714D5A3B85; Thu, 9 Dec 2021 07:51:55 +0000 (UTC) Date: Thu, 9 Dec 2021 08:51:54 +0100 From: Michal Hocko To: Joel Savitz Cc: Andrew Morton , linux-kernel , Waiman Long , linux-mm@kvack.org, Nico Pache , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Darren Hart , Davidlohr Bueso , =?iso-8859-1?Q?Andr=E9?= Almeida Subject: Re: [PATCH] mm/oom_kill: wake futex waiters before annihilating victim shared mutex Message-ID: References: <20211207214902.772614-1-jsavitz@redhat.com> <20211207154759.3f3fe272349c77e0c4aca36f@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 592F6140002 X-Stat-Signature: gt7bo75e6qpmw4px33dgucho4q7f8p5c Authentication-Results: imf26.hostedemail.com; dkim=pass header.d=suse.com header.s=susede1 header.b=XLMyk2a6; spf=pass (imf26.hostedemail.com: domain of mhocko@suse.com designates 195.135.220.28 as permitted sender) smtp.mailfrom=mhocko@suse.com; dmarc=pass (policy=quarantine) header.from=suse.com X-HE-Tag: 1639036317-212437 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: On Wed 08-12-21 21:59:29, Joel Savitz wrote: > On Wed, Dec 8, 2021 at 11:05 AM Michal Hocko wrote: [...] > > I have had a closer look and I guess I can see what you are trying to > > achieve. futex_exit_release is normally called from exit_mm context. You > > are likely seeing a situation when the oom victim is blocked and cannot > > exit. That is certainly possible but it shouldn't be a permanent state. > > So I would be more interested about your particular issue and how long > > the task has been stuck unable to exit. > > Before applying this patch I never saw a task eventually exit during > the reproduction of this system state. What has happened to the oom victim and why it has never exited? Side note. I have noticed that you have sent v2 with minor changes. It is usualy better to resolve review feedback before posting a new version. Discussion gets rather hard to follow otherwise. Thanks! -- Michal Hocko SUSE Labs