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=-4.0 required=3.0 tests=BAYES_00,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 A5B50C433E3 for ; Thu, 16 Jul 2020 13:54:50 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 73BBA207BC for ; Thu, 16 Jul 2020 13:54:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 73BBA207BC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id E9D8F6B0072; Thu, 16 Jul 2020 09:54:49 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E4D396B0075; Thu, 16 Jul 2020 09:54:49 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D64866B007B; Thu, 16 Jul 2020 09:54:49 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0048.hostedemail.com [216.40.44.48]) by kanga.kvack.org (Postfix) with ESMTP id C00366B0072 for ; Thu, 16 Jul 2020 09:54:49 -0400 (EDT) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 4C5B01EF1 for ; Thu, 16 Jul 2020 13:54:49 +0000 (UTC) X-FDA: 77044084698.13.food17_220ea2e26f02 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin13.hostedemail.com (Postfix) with ESMTP id 1CEFC18140B60 for ; Thu, 16 Jul 2020 13:54:49 +0000 (UTC) X-HE-Tag: food17_220ea2e26f02 X-Filterd-Recvd-Size: 3427 Received: from mail-wm1-f66.google.com (mail-wm1-f66.google.com [209.85.128.66]) by imf32.hostedemail.com (Postfix) with ESMTP for ; Thu, 16 Jul 2020 13:54:48 +0000 (UTC) Received: by mail-wm1-f66.google.com with SMTP id 17so11701831wmo.1 for ; Thu, 16 Jul 2020 06:54:48 -0700 (PDT) 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:in-reply-to; bh=65QcCnpAmDce81oUaFA3QmWLjs//tlPa4Tv3XmT8+FQ=; b=UgzDj5apGeLlMyxyFHCrgnmBAQECcBbVZY1ZIocMQBzsFxxb+iWPGTsyOfQlJ7dt8P EX6ve4l8d4V0h3UfQJidsDT9tWxS4/G2MEeBiPDSHv8OpWvBEk8doPdlI/nUDPGtomLK b1O2RJMRAwyKDPM7+26bgr1n4qbD2RSW8rvIKMSBOpl+9KlZcGuAFJCN7YXztEpXQm05 03LRC+BclrSmclso8gMdIgRe+hruyWTIgwLKBBRR4afT/JBatWOCn11Ck8YA+iSzM+fn kt+gqWlXc2CW2SUOVkyM3Ek8XLnKswRaZl84ZPxWIB3ZiaqTk0AEpZqRtMm7++z0hhdK mQ5A== X-Gm-Message-State: AOAM5323Pv8r9ewP9u8JS0yV4vG+vbMXJCrWiuSHBcH9LCvRjqeyESLj TogIV5Rk48TVWh8gq5hCvSs= X-Google-Smtp-Source: ABdhPJyj2yoIu1OI5sYIfY/IP84jBUda+jO/u4IzsW4mJwUw1NjKcW5ImRsOWLC2FicYTufKJVMauQ== X-Received: by 2002:a05:600c:218f:: with SMTP id e15mr4169276wme.63.1594907687641; Thu, 16 Jul 2020 06:54:47 -0700 (PDT) Received: from localhost (ip-37-188-169-187.eurotel.cz. [37.188.169.187]) by smtp.gmail.com with ESMTPSA id k20sm8457168wmi.27.2020.07.16.06.54.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Jul 2020 06:54:46 -0700 (PDT) Date: Thu, 16 Jul 2020 15:54:45 +0200 From: Michal Hocko To: Tetsuo Handa Cc: Greg Kroah-Hartman , Arve Hjonnevag , Todd Kjos , Martijn Coenen , Joel Fernandes , Christian Brauner , syzbot , acme@kernel.org, alexander.shishkin@linux.intel.com, jolsa@redhat.com, linux-kernel@vger.kernel.org, mark.rutland@arm.com, mingo@redhat.com, namhyung@kernel.org, peterz@infradead.org, syzkaller-bugs@googlegroups.com, "open list:ANDROID DRIVERS" , linux-mm Subject: Re: [PATCH] binder: Don't use mmput() from shrinker function. Message-ID: <20200716135445.GN31089@dhcp22.suse.cz> References: <0000000000001fbbb605aa805c9b@google.com> <5ce3ee90-333e-638d-ac8c-cd6d7ab7aa3b@I-love.SAKURA.ne.jp> <20200716083506.GA20915@dhcp22.suse.cz> <36db7016-98d6-2c6b-110b-b2481fd480ac@i-love.sakura.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <36db7016-98d6-2c6b-110b-b2481fd480ac@i-love.sakura.ne.jp> X-Rspamd-Queue-Id: 1CEFC18140B60 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: On Thu 16-07-20 22:41:14, Tetsuo Handa wrote: > On 2020/07/16 17:35, Michal Hocko wrote: [...] > > But in order for this to happen the shrinker would have to do the last > > put on the mm. But mm cannot go away from under uprobe_mmap so those two > > paths cannot race with each other. > > and mm1 != mm2 is possible, isn't it? OK, I have missed that information. You are right. Can you make this into the changelog please? -- Michal Hocko SUSE Labs