From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759216AbXGRUJR (ORCPT ); Wed, 18 Jul 2007 16:09:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754078AbXGRUJA (ORCPT ); Wed, 18 Jul 2007 16:09:00 -0400 Received: from smtp2.linux-foundation.org ([207.189.120.14]:51682 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753313AbXGRUI7 (ORCPT ); Wed, 18 Jul 2007 16:08:59 -0400 Date: Wed, 18 Jul 2007 13:08:33 -0700 (PDT) From: Linus Torvalds To: Paul Fulghum cc: James Simmons , Alan Cox , Linux Kernel Mailing List , Linux console project Subject: Re: [PATCH] Use tty_schedule in VT code. In-Reply-To: <1184783279.3444.15.camel@x2.microgate.com> Message-ID: References: <469D2810.9080109@microgate.com> <1184783279.3444.15.camel@x2.microgate.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 18 Jul 2007, Paul Fulghum wrote: > > It might be safest to drop this portion so you can get the > obvious part of the patch accepted (consolidating > the redundant xxx_schedule_flip functions). But wasn't the whole _point_ that con_schedule_flip() potentially gets called from interrupt context, and thus that part is wrong. It's why con_schedule_flip() was different from tty_schedule_flip() to begin with, no? If a tty driver has marked itself low-latency, it's still wrong to do the flush_to_ldisc() from interrupt context if a console event happens in interrupt context. I thought that was the whole *point* of the difference between "tty_schedule_flip()" and "con_schedule_flip()", as far as I know. The "con_schedule_flip()" can be called from any context (console messages), while "tty_schedule_flip()" is only called from well-behaved tty layer. But I really don't know. I used to be involved with the tty layer, these days I'd rather avoid it. This "simple" patch seems to be anything but, and I'd like somebody to just make sure that all the issues are taken care of. Alan? Linus