From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754078AbdCBGPk (ORCPT ); Thu, 2 Mar 2017 01:15:40 -0500 Received: from LGEAMRELO12.lge.com ([156.147.23.52]:37841 "EHLO lgeamrelo12.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750717AbdCBGPj (ORCPT ); Thu, 2 Mar 2017 01:15:39 -0500 X-Original-SENDERIP: 156.147.1.126 X-Original-MAILFROM: byungchul.park@lge.com X-Original-SENDERIP: 10.177.220.156 X-Original-MAILFROM: byungchul.park@lge.com From: "byungchul.park" To: "'Matthew Wilcox'" , "'Peter Zijlstra'" Cc: , , , , , , , , , , References: <1484745459-2055-1-git-send-email-byungchul.park@lge.com> <1484745459-2055-7-git-send-email-byungchul.park@lge.com> <20170228181547.GM5680@worktop> <20170302042021.GN16328@bombadil.infradead.org> In-Reply-To: <20170302042021.GN16328@bombadil.infradead.org> Subject: RE: [PATCH v5 06/13] lockdep: Implement crossrelease feature Date: Thu, 2 Mar 2017 13:45:35 +0900 Message-ID: <004101d2930f$d51a9f90$7f4fdeb0$@lge.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 14.0 Thread-Index: AQG5iAPnNJpN+0e1bSMvdFjLCPpxTANAdmBUAZm//oMCViLIlKF5ix7w Content-Language: ko Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > -----Original Message----- > From: Matthew Wilcox [mailto:willy@infradead.org] > Sent: Thursday, March 02, 2017 1:20 PM > To: Peter Zijlstra > Cc: Byungchul Park; mingo@kernel.org; tglx@linutronix.de; > walken@google.com; boqun.feng@gmail.com; kirill@shutemov.name; linux- > kernel@vger.kernel.org; linux-mm@kvack.org; iamjoonsoo.kim@lge.com; > akpm@linux-foundation.org; npiggin@gmail.com > Subject: Re: [PATCH v5 06/13] lockdep: Implement crossrelease feature > > On Tue, Feb 28, 2017 at 07:15:47PM +0100, Peter Zijlstra wrote: > > (And we should not be returning to userspace with locks held anyway -- > > lockdep already has a check for that). > > Don't we return to userspace with page locks held, eg during async > directio? Hello, I think that the check when returning to user with crosslocks held should be an exception. Don't you think so? Thanks, Byungchul