From mboxrd@z Thu Jan 1 00:00:00 1970 From: doug lkml Subject: Re: Query about might_sleep() Date: Thu, 27 Feb 2014 09:48:45 +0530 Message-ID: References: <20140226215506.246b9124@gandalf.local.home> <20140226225018.47eec511@gandalf.local.home> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: linux-rt-users@vger.kernel.org To: Steven Rostedt Return-path: Received: from mail-ve0-f196.google.com ([209.85.128.196]:55777 "EHLO mail-ve0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754712AbaB0ESq (ORCPT ); Wed, 26 Feb 2014 23:18:46 -0500 Received: by mail-ve0-f196.google.com with SMTP id jw12so886674veb.11 for ; Wed, 26 Feb 2014 20:18:46 -0800 (PST) In-Reply-To: <20140226225018.47eec511@gandalf.local.home> Sender: linux-rt-users-owner@vger.kernel.org List-ID: >> >> local_irq_save(); >> some_function(); >> rt_spin_lock() --> this calls __might_sleep >> local_irq_restore(); --> In this case there's a bug right? > > Yes, that's a bug. And that's why you'll see a lot of updates in the > -rt patch with things like: local_irq_save_nort(). And this is also the > cause of some of the #ifdef CONFIG_PREEMPT_RT_FULL. And what makes this > change so challenging ;-) That clarifies my question. Thanks.