Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753586AbYFBObV (ORCPT ); Mon, 2 Jun 2008 10:31:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750986AbYFBObJ (ORCPT ); Mon, 2 Jun 2008 10:31:09 -0400 Received: from rv-out-0506.google.com ([209.85.198.229]:62742 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751215AbYFBObI (ORCPT ); Mon, 2 Jun 2008 10:31:08 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=hxf19WOLUFlzZoJ9/2bt6vkX+JWiJH1kKtZbwBvPDuPLycXkNf9OL5hrN3E/iigKf9cbVg4WOEyrRRY8k/Q4frqFzd8t+ZZXsqMhWBhekHFp0SBtGXbK6iwR+cGhtCaNE8F4ytTay4BW2oT4/2sIrHhzZMH1w5HKqDjow2pxR7o= Message-ID: <19f34abd0806020731u3d89cfe2m4eef743b377a13ec@mail.gmail.com> Date: Mon, 2 Jun 2008 16:31:07 +0200 From: "Vegard Nossum" To: "Alan Cox" Subject: Re: 2.6.25.3: su gets stuck for root Cc: "Alan Cox" , "David Newall" , "Willy Tarreau" , "Harald Dunkel" , "Joe Peterson" , linux-kernel@vger.kernel.org In-Reply-To: <20080602122819.GA25136@devserv.devel.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <48434D57.6030801@skyrush.com> <20080602053256.GF5609@1wt.eu> <20080602091016.571dda7c@core> <4843B6EE.8080104@davidnewall.com> <20080602102033.63e4cd18@core> <19f34abd0806020316v4135935dxff04bcf663ebd4bf@mail.gmail.com> <19f34abd0806020339m100fd3f8m6c0c6ff0c08a66d2@mail.gmail.com> <20080602105210.GH18697@devserv.devel.redhat.com> <19f34abd0806020357w6478704dt50226f51c6c62701@mail.gmail.com> <20080602122819.GA25136@devserv.devel.redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1344 Lines: 38 On Mon, Jun 2, 2008 at 2:28 PM, Alan Cox wrote: > On Mon, Jun 02, 2008 at 12:57:07PM +0200, Vegard Nossum wrote: >> I guess this still doesn't explain why TTOU doesn't block (IOW, stop >> the process, right?) in this case, because my test program does not >> touch it. > > I see the parent process sleeping and the child taking TTOU and going to > state T. That again is correct. > > alan 3219 0.0 0.0 3652 384 pts/5 S 13:11 0:00 ./repro > alan 3220 0.0 0.0 3652 204 pts/5 T 13:11 0:00 ./repro > > If you run it without any straces etc do you see it blocked in T or sitting > in R ? Without any straces, it is blocked in T. Like Joe's report. With strace, it's in R. Exactly as you said, correct and expected behaviour. So this is not a kernel problem at all. I'm sorry for having wasted your time :-( Vegard -- "The animistic metaphor of the bug that maliciously sneaked in while the programmer was not looking is intellectually dishonest as it disguises that the error is the programmer's own creation." -- E. W. Dijkstra, EWD1036 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/