Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751645Ab1FCKXh (ORCPT ); Fri, 3 Jun 2011 06:23:37 -0400 Received: from mail4.comsite.net ([205.238.176.238]:60118 "EHLO mail4.comsite.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750984Ab1FCKXf (ORCPT ); Fri, 3 Jun 2011 06:23:35 -0400 X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=71.22.127.106; From: Milton Miller To: Linus Torvalds , Greg Kroah-Hartman Cc: , Alan Cox , Benjamin Herrenschmidt , Stefan Bigler , Toby Gray , Felipe Balbi Subject: Re: tty breakage in X (Was: tty vs workqueue oddities) Date: Fri, 03 Jun 2011 05:23:12 -0500 X-Originating-IP: 71.22.127.106 Message-ID: <1307096592_10534@mail4.comsite.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1227 Lines: 30 [not on list so made up cc list] On Fri Jun 03 2011 about 05:37:52 EST, Linus wrote: > On Fri, Jun 3, 2011 at 3:56 PM, Benjamin Herrenschmidt wrote: > > So I think my theory stands that flush_to_ldisc constantly reschedule > > itself causing the worker thread to eat all CPU and starve the consumer > > of the PTY. I won't have time to dig much deeper today nor probably this > > week-end so I'm sending this email for others who want to look. > > Gaah - that commit is total and utter crap. > > I *removed* the whole "reschedule the work queue again" crap. It was > totally wrong. See commit a5660b41af6a. > > But then commit b1c43f82c5aa added the crap right back in. > > So does it all work if you just remove the broken schedule_work() line > from flush_to_ldisc? > > Otherwise we'll need to just revert it. The commit is clearly totally broken. Its further broken in that the recieve_buf functions return -ERRORS but the callers don't check for negative values. milton -- 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/