From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756063Ab1HSPBS (ORCPT ); Fri, 19 Aug 2011 11:01:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:5121 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755821Ab1HSPBO (ORCPT ); Fri, 19 Aug 2011 11:01:14 -0400 Date: Fri, 19 Aug 2011 16:58:15 +0200 From: Oleg Nesterov To: Kay Sievers Cc: Lennart Poettering , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-man@vger.kernel.org, roland@hack.frob.com, torvalds@linux-foundation.org Subject: Re: + prctl-add-pr_setget_child_reaper-to-allow-simple-process-supervision .patch added to -mm tree Message-ID: <20110819145815.GA15420@redhat.com> References: <20110817134516.GA14136@redhat.com> <20110818124353.GA2839@tango.0pointer.de> <20110818142508.GA30959@redhat.com> <1313691091.1107.9.camel@mop> <20110818184857.GA12094@redhat.com> <1313717521.991.4.camel@mop> <20110819122503.GA8411@redhat.com> <20110819131339.GB8411@redhat.com> <1313763653.1119.12.camel@mop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1313763653.1119.12.camel@mop> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/19, Kay Sievers wrote: > > On Fri, 2011-08-19 at 15:13 +0200, Oleg Nesterov wrote: > > On 08/19, Kay Sievers wrote: > > > But this has other (OK, minor) problems too, afaics. First of all, this > > ->has_child_subreaper = T is not right when the caller exits. We should > > not look for ->is_child_subreaper parent, our children should to find us. > > > > Right? > > The flags are still inherited. If the subreaper isn't there anymore, we > will look it up and not find it. I think that's ok for the very unusual > case that a service manager goes away and its children still run. We > will just fall back to the usual PID 1 logic. Yes, yes, I didn't mean this is really buggy. Just a bit "strange". Anyway, this is fixed in v4 you sent. > version 4: Looks correct... But I don't trust myself. Especially after I missed the problem with klthreads ;) I'll try to re-read this patch carefully tomorrow with a fresh head. Oleg.