Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934789AbYCFOqa (ORCPT ); Thu, 6 Mar 2008 09:46:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757999AbYCFOqN (ORCPT ); Thu, 6 Mar 2008 09:46:13 -0500 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:2001 "EHLO spitz.ucw.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1759545AbYCFOqL (ORCPT ); Thu, 6 Mar 2008 09:46:11 -0500 Date: Wed, 5 Mar 2008 20:47:06 +0100 From: Pavel Machek To: Suresh Siddha Cc: Ingo Molnar , Christoph Hellwig , hpa@zytor.com, tglx@linutronix.de, andi@firstfloor.org, linux-kernel@vger.kernel.org, Arjan van de Ven Subject: Re: [patch 2/2] x86, fpu: lazy allocation of FPU area - v3 Message-ID: <20080305194705.GA4386@ucw.cz> References: <20080303230335.892214000@linux-os.sc.intel.com> <20080303230336.042604000@linux-os.sc.intel.com> <20080304012012.GB22431@infradead.org> <20080304014306.GC28006@linux-os.sc.intel.com> <20080304103220.GA17621@elte.hu> <20080304175528.GD28006@linux-os.sc.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080304175528.GD28006@linux-os.sc.intel.com> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1405 Lines: 33 On Tue 2008-03-04 09:55:28, Suresh Siddha wrote: > On Tue, Mar 04, 2008 at 11:32:20AM +0100, Ingo Molnar wrote: > > > > * Suresh Siddha wrote: > > > > > On Mon, Mar 03, 2008 at 08:20:12PM -0500, Christoph Hellwig wrote: > > > > On Mon, Mar 03, 2008 at 03:02:46PM -0800, Suresh Siddha wrote: > > > > > + /* > > > > > + * Memory allocation at the first usage of the FPU and other state. > > > > > + */ > > > > > + if (!tsk->thread.xstate) > > > > > + tsk->thread.xstate = kmem_cache_alloc(task_xstate_cachep, GFP_KERNEL); > > > > > > > > Also don't we need some kind of error handling here? > > > > > > Currently it uses SLAB_PANIC. > > > > but SLAB_PANIC only covers kmem_cache_create() failures. > > > > kmem_cache_alloc() can fail (return NULL) and not handling it is a bug. > > oops. you are correct. Will send a sigsegv in the failure case then. Thanks. You are introducing possibility of hard to debug error, where previous code just worked... Does not look like good idea to me. -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- 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/