From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752929Ab1HAMkC (ORCPT ); Mon, 1 Aug 2011 08:40:02 -0400 Received: from casper.infradead.org ([85.118.1.10]:52338 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752616Ab1HAMjz (ORCPT ); Mon, 1 Aug 2011 08:39:55 -0400 Subject: Re: threaded interrupt handlers: what if hardirq part not disables device interrupt? From: Peter Zijlstra To: Remy Bohmer Cc: Thomas Gleixner , linux-rt-users , LKML , Jason Wessel In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Date: Mon, 01 Aug 2011 14:44:38 +0200 Message-ID: <1312202678.2617.460.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2011-07-31 at 16:15 +0200, Remy Bohmer wrote: > As alternative solution I can do the following as well: > The driver now has a tasklet used for processing the queue. If I add > IRQF_NO_THREAD as irq-flag, the thread is not created and the handler > runs completely in hard-irq context. This seems to work okay, but it > does not feel as the right solution. > > How is this supposed to work? Do you have better ideas how to solve > situations like this? This sounds like the total trainwreck known as tty/console, I believe jwessel and tglx had some ideas on that. Maybe Jason can share what he knows, I'm not up to speed on that issue.