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=-8.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 9C5B0C64E7B for ; Tue, 1 Dec 2020 12:37:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3BE4320857 for ; Tue, 1 Dec 2020 12:37:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="J7GV2szf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727156AbgLAMhb (ORCPT ); Tue, 1 Dec 2020 07:37:31 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:58965 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727109AbgLAMhb (ORCPT ); Tue, 1 Dec 2020 07:37:31 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1606826165; h=from:from:reply-to:subject:subject: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=493pPRQ1cbcXG7JuRF1/JbMIArV86P0mGsjOr36MtbE=; b=J7GV2szf8w97Y6Jmc8u0Hcbw81ZNUF+tGCWovg3fLYCYR3QGB67xZ3wR1NRpsLTUJkLXm2 ZPdQ2jiGeim+ViRhD3oyfcTeRRJI0+JRYNvEzHTYxcPCXeiuvctyNCt5WO8cqPZtJx1225 ACx5P/sKY+AUsUZuOSlVL08zbTS/p0U= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-140-5ZRgk0Z7N4-aZFRnblE5pw-1; Tue, 01 Dec 2020 07:36:01 -0500 X-MC-Unique: 5ZRgk0Z7N4-aZFRnblE5pw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 35F921E7D2; Tue, 1 Dec 2020 12:36:00 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.40.192.135]) by smtp.corp.redhat.com (Postfix) with SMTP id F12E760BE5; Tue, 1 Dec 2020 12:35:57 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Tue, 1 Dec 2020 13:35:59 +0100 (CET) Date: Tue, 1 Dec 2020 13:35:56 +0100 From: Oleg Nesterov To: "Eric W. Biederman" Cc: Wen Yang , Alexey Dobriyan , Christian Brauner , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH] proc: add locking checks in proc_inode_is_dead Message-ID: <20201201123556.GB2700@redhat.com> References: <20201128175850.19484-1-wenyang@linux.alibaba.com> <87zh2yit5u.fsf@x220.int.ebiederm.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87zh2yit5u.fsf@x220.int.ebiederm.org> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 11/30, Eric W. Biederman wrote: > > Ouch!!!! Oleg I just looked the introduction of proc_inode_is_dead in > d855a4b79f49 ("proc: don't (ab)use ->group_leader in proc_task_readdir() > paths") introduced a ``regression''. > > Breaking the logic introduced in 7d8952440f40 ("[PATCH] procfs: Fix > listing of /proc/NOT_A_TGID/task") to keep those directory listings not > showing up. Sorry, I don't understand... Do you mean that "ls /proc/pid/task" can see an empty dir? Afaics this was possible before d855a4b79f49 too. Or what? Oleg.