Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265197AbUFMQA1 (ORCPT ); Sun, 13 Jun 2004 12:00:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265201AbUFMQA0 (ORCPT ); Sun, 13 Jun 2004 12:00:26 -0400 Received: from gprs214-6.eurotel.cz ([160.218.214.6]:24448 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S265197AbUFMQAY (ORCPT ); Sun, 13 Jun 2004 12:00:24 -0400 Date: Sun, 13 Jun 2004 17:59:59 +0200 From: Pavel Machek To: Dave Jones , Andrew Morton , Nigel Cunningham , herbert@gondor.apana.org.au, mochel@digitalimplant.org, linux-kernel@vger.kernel.org Subject: Re: Fix memory leak in swsusp Message-ID: <20040613155959.GB2683@elf.ucw.cz> References: <20040610105629.GA367@gondor.apana.org.au> <20040610212448.GD6634@elf.ucw.cz> <20040610233707.GA4741@gondor.apana.org.au> <20040611094844.GC13834@elf.ucw.cz> <20040611101655.GA8208@gondor.apana.org.au> <20040611102327.GF13834@elf.ucw.cz> <20040611110314.GA8592@gondor.apana.org.au> <40CA75CA.2030209@linuxmail.org> <20040611210059.2522e02d.akpm@osdl.org> <20040612111016.GA23441@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040612111016.GA23441@redhat.com> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.5.1+cvs20040105i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1205 Lines: 26 Hi! > > > We were avoiding the use of memcpy because it messes up the preempt count with 3DNow, and > > > potentially as other unseen side effects. The preempt could possibly simply be reset at resume time, > > > but the point remains. > > > > eh? memcpy just copies memory. Maybe your meant copy_*_user()? > > See arch/i386/lib/memcpy.c The 3dnow routine does kernel_fpu_begin()/..end() > which futzes with preempt count. What I'm missing though is that the count > afterwards should be the same as it was before the memcpy. Why is this > a problem for the suspend folks? It does not hurt here, but as someone else explained already it is a problem when doing atomic copy of memory. (You increment, than copy whole memory, you decrement; but you only decrement in original, not in copy...) Pavel -- People were complaining that M$ turns users into beta-testers... ...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl! - 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/