From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: [Bug #15041] Pagemap endless read loop with LTP Date: Thu, 14 Jan 2010 00:50:10 +0100 Message-ID: <20100113235010.GF24818@basil.fritz.box> References: <2375c9f91001121904h2857760akbf2dd2c9f7441fc5@mail.gmail.com> <201001132257.34123.rjw@sisk.pl> Mime-Version: 1.0 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <201001132257.34123.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="iso-8859-1" To: "Rafael J. Wysocki" Cc: =?iso-8859-1?Q?Am=E9rico?= Wang , Andi Kleen , Linux Kernel Mailing List , Kernel Testers List On Wed, Jan 13, 2010 at 10:57:34PM +0100, Rafael J. Wysocki wrote: > On Wednesday 13 January 2010, Am=E9rico Wang wrote: > > On Mon, Jan 11, 2010 at 6:32 AM, Rafael J. Wysocki wr= ote: > > > This message has been generated automatically as a part of a repo= rt > > > of recent regressions. > > > > > > The following bug entry is on the current list of known regressio= ns > > > from 2.6.32. Please verify if it still should be listed and let = me know > > > (either way). > > > > > > > > > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=3D15= 041 > > > Subject : Pagemap endless read loop with LTP > > > Submitter : Andi Kleen > > > Date : 2010-01-10 2:09 (1 days old) > > > References : http://marc.info/?l=3Dlinux-kernel&m=3D12630894= 1423848&w=3D4 > > > > >=20 > > According to Andi's later reply, it shoud not be an endless loop, > > it just takes a rather long time. >=20 > Andi? It'll try to read 47 bits worth of 0s on 64bit x86-64.=20 I haven't tried to wait until that finishes, but I estimate a few month= s of=20 CPU time at least. The interface is just misdesigned, but I guess we cannot do anything about that for now. LTP will just need to do a workaround. This unfortunately breaks older LTP versions. -Andi --=20 ak@linux.intel.com -- Speaking for myself only.