Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261249AbVBVVRS (ORCPT ); Tue, 22 Feb 2005 16:17:18 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261255AbVBVVRR (ORCPT ); Tue, 22 Feb 2005 16:17:17 -0500 Received: from gate.crashing.org ([63.228.1.57]:6623 "EHLO gate.crashing.org") by vger.kernel.org with ESMTP id S261249AbVBVVRI (ORCPT ); Tue, 22 Feb 2005 16:17:08 -0500 Subject: Re: [PATCH/RFC] Futex mmap_sem deadlock From: Benjamin Herrenschmidt To: Linus Torvalds Cc: Olof Johansson , Kernel Mailing List , Andrew Morton , jamie@shareable.org, Rusty Russell , David Howells In-Reply-To: References: <20050222190646.GA7079@austin.ibm.com> Content-Type: text/plain Date: Wed, 23 Feb 2005 08:16:09 +1100 Message-Id: <1109106969.5412.138.camel@gaston> Mime-Version: 1.0 X-Mailer: Evolution 2.0.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 586 Lines: 17 On Tue, 2005-02-22 at 11:36 -0800, Linus Torvalds wrote: > DavidH - what's the word on nested read-semaphores like this? Are they > supposed to work (like nested read-spinlocks), or do we need to do the > things Olof does? Isn't Olof scheme racy ? Can't the stuff get swapped out between the first get_user() and the "real" one ? Ben. - 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/