Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757246AbZJBRCE (ORCPT ); Fri, 2 Oct 2009 13:02:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756745AbZJBRCD (ORCPT ); Fri, 2 Oct 2009 13:02:03 -0400 Received: from kroah.org ([198.145.64.141]:42847 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756007AbZJBRCB (ORCPT ); Fri, 2 Oct 2009 13:02:01 -0400 Date: Fri, 2 Oct 2009 09:59:37 -0700 From: Greg KH To: Johan Hovold Cc: "Eric W. Biederman" , Greg Kroah-Hartman , Alan Cox , Michael Trimarchi , Oliver Neukum , linux-usb@vger.kernel.org, Alan Cox , Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [PATCH] USB: ftdi_sio: Remove tty->low_latency. Message-ID: <20091002165937.GA4007@kroah.com> References: <20090924154023.GA27480@localhost> <200909242103.48562.oliver@neukum.org> <20090924202107.4730f2af@lxorguk.ukuu.org.uk> <20090924211459.GB27963@localhost> <4ABD020B.4040901@gandalf.sssup.it> <20090929145514.GF2152@localhost> <20090929235232.1ae6c63b@lxorguk.ukuu.org.uk> <20091002084755.GA7382@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20091002084755.GA7382@localhost> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1349 Lines: 37 On Fri, Oct 02, 2009 at 10:47:55AM +0200, Johan Hovold wrote: > On Thu, Oct 01, 2009 at 07:52:21PM -0700, Eric W. Biederman wrote: > > Alan Cox writes: > > > > >> As it stands today ftdi_sio does indeed call tty_flip_buffer_push from > > >> interrupt context with low_latency set and that is obviously incorrect, > > >> right? > > > > > > It seems to do it from a work queue - or did I miss a case ? > > > > ftdi_sio crash quite regularly for me with 2.6.31. > > > > With a bunch of nasties like: > > BUG: scheduling while atomic: swapper/0/0x00010000 > > bad: scheduling from the idle thread! > > It's the same problem. > > Greg, can't we apply the patch for stable at least? Then we can massage > ftdi_sio into actually using the work queue for doing _all_ processing > in the meantime if deemed necessary. Patches need to be in Linus's tree first, before they can get into the -stable releases. I'm still digging through my patch queue, sorry, been swamped with the -stable stuff, due to the merge window and 4 conferences over the past 2 weeks... thanks, greg k-h -- 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/