From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.11] helo=sc8-sf-mx1.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1CEBIU-00038n-Mg for user-mode-linux-devel@lists.sourceforge.net; Sun, 03 Oct 2004 11:41:26 -0700 Received: from cyphermail.sandelman.ottawa.on.ca ([205.150.200.161] helo=noxmail.sandelman.ottawa.on.ca) by sc8-sf-mx1.sourceforge.net with esmtp (TLSv1:DES-CBC3-SHA:168) (Exim 4.41) id 1CEBGd-00028B-SI for user-mode-linux-devel@lists.sourceforge.net; Sun, 03 Oct 2004 11:41:26 -0700 Subject: Re: [uml-devel] T-mode processes In-Reply-To: Message from Henrik Nordstrom of "Sun, 03 Oct 2004 19:55:30 +0200." References: <29246.1096763190@marajade.sandelman.ottawa.on.ca> <29392.1096824373@marajade.sandelman.ottawa.on.ca> Mime-Version: 1.0 (generated by tm-edit 1.8) Content-Type: text/plain; charset=US-ASCII Message-ID: <30745.1096828767@marajade.sandelman.ottawa.on.ca> From: Michael Richardson Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: The user-mode Linux development list List-Post: List-Help: List-Subscribe: , List-Archive: Date: Sun, 03 Oct 2004 14:39:27 -0400 To: Henrik Nordstrom Cc: user-mode-linux-devel -----BEGIN PGP SIGNED MESSAGE----- >>>>> "Henrik" == Henrik Nordstrom writes: >> It may well be, but it isn't acceptable. What would break if >> kill-9 got rid of processes being PTRACE'ed? Henrik> This discussion probably is more related to lkml than uml.. Sure. Henrik> For one thing the SIGKILL needs to be notified to and acted Henrik> upon by the tracing parent process before it is delivered to Henrik> the killed process. It is possible (and certainly so in case Henrik> of UML) that the tracing parent wants to do something Henrik> entirely different when a traced whild receives SIGKILL or Henrik> other terminal action. I can't see a use for this :-) At least, when the tracing process has gone away, then the SIGKILL should take effect. Henrik> The actual question is why a process can be left in traced Henrik> state without any parent tracing it.. You'll see the same Henrik> symptoms if you strace a process and then kills strace. My Henrik> guess is that this is from the basic question on how to Henrik> determine what to do with the traced process when the Henrik> tracing parent disappears without telling what the future Henrik> fate of this process should be.. neither killing or Henrik> untracing the process is safe options. Henrik> Any way, sending a SIGCONT to the stopped process gets it Henrik> going again, or killed in case a SIGKILL or other terminal Henrik> action is pending. Our test bed produces a dozen of these every night. If someone has an idea on how to get better intel on this, I'm happy to cooperate. - -- ] "Elmo went to the wrong fundraiser" - The Simpson | firewalls [ ] Michael Richardson, Xelerance Corporation, Ottawa, ON |net architect[ ] mcr@xelerance.com http://www.sandelman.ottawa.on.ca/mcr/ |device driver[ ] panic("Just another Debian GNU/Linux using, kernel hacking, security guy"); [ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.2 (GNU/Linux) Comment: Finger me for keys iQCVAwUBQWBHXoqHRg3pndX9AQEa6QP/TueVomIuseyLAuF9ZyUadncSwrQXIM3H aGBul3l1mmtCr34G0f1vJItvWXUW1MDLZ+hHiFIIh63zkeOWboklKMrRbSPxFC13 Er2peBRxNZ+EGUosEQaMcKktxHn9ktoWifHzcOwvUITTVp4DT+Sp9AuTNObMqTBG ZIEPnFmjPSg= =Vub3 -----END PGP SIGNATURE----- ------------------------------------------------------- This SF.net email is sponsored by: IT Product Guide on ITManagersJournal Use IT products in your business? Tell us what you think of them. Give us Your Opinions, Get Free ThinkGeek Gift Certificates! Click to find out more http://productguide.itmanagersjournal.com/guidepromo.tmpl _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel