Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762866AbXFAVbs (ORCPT ); Fri, 1 Jun 2007 17:31:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759910AbXFAVbl (ORCPT ); Fri, 1 Jun 2007 17:31:41 -0400 Received: from caramon.arm.linux.org.uk ([217.147.92.249]:3248 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759162AbXFAVbk (ORCPT ); Fri, 1 Jun 2007 17:31:40 -0400 Date: Fri, 1 Jun 2007 22:31:30 +0100 From: Russell King To: Maximus Cc: linux-kernel@vger.kernel.org Subject: Re: dma_alloc_coherent fails Message-ID: <20070601213129.GC5400@flint.arm.linux.org.uk> Mail-Followup-To: Maximus , linux-kernel@vger.kernel.org References: <3634de740706010946iabd6c51rf7e9a36463e3fca3@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3634de740706010946iabd6c51rf7e9a36463e3fca3@mail.gmail.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 731 Lines: 21 On Fri, Jun 01, 2007 at 10:16:41PM +0530, Maximus wrote: > Hi, > Am using a linux 2.6.19 kernel for arm. the dma_alloc_coherent > function call in the kernel for 38400 bytes fails. > > Has anyone faced this problem before?. > > What could be make dma_alloc_coherent to success sometimes and fail > sometimes?. Memory fragmentation. Large allocations (> 1 page) are always unreliable. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: - 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/