From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753972Ab2A3HoE (ORCPT ); Mon, 30 Jan 2012 02:44:04 -0500 Received: from mailout2.w1.samsung.com ([210.118.77.12]:65372 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752477Ab2A3HoC (ORCPT ); Mon, 30 Jan 2012 02:44:02 -0500 Date: Mon, 30 Jan 2012 08:43:55 +0100 From: Marek Szyprowski Subject: RE: [Linaro-mm-sig] [PATCH 12/15] drivers: add Contiguous Memory Allocator In-reply-to: To: "'Ohad Ben-Cohen'" Cc: "'Clark, Rob'" , "'Daniel Walker'" , "'Russell King'" , "'Arnd Bergmann'" , "'Jonathan Corbet'" , "'Mel Gorman'" , "'Jesse Barker'" , linux-kernel@vger.kernel.org, "'Michal Nazarewicz'" , "'Dave Hansen'" , linaro-mm-sig@lists.linaro.org, linux-mm@kvack.org, "'Kyungmin Park'" , "'KAMEZAWA Hiroyuki'" , "'Andrew Morton'" , linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org Message-id: <014101ccdf22$eb610d30$c2232790$%szyprowski@samsung.com> Organization: SPRC MIME-version: 1.0 X-Mailer: Microsoft Office Outlook 12.0 Content-type: text/plain; charset=us-ascii Content-language: pl Content-transfer-encoding: 7BIT Thread-index: Aczd7rSrErMaQJiMTruMIKnZ/6ImqwBLOIdg References: <1327568457-27734-1-git-send-email-m.szyprowski@samsung.com> <1327568457-27734-13-git-send-email-m.szyprowski@samsung.com> <00de01ccdce1$e7c8a360$b759ea20$%szyprowski@samsung.com> <010301ccdd03$1ad15ab0$50741010$%szyprowski@samsung.com> <010501ccdd06$b9844f20$2c8ced60$%szyprowski@samsung.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Saturday, January 28, 2012 7:57 PM Ohad Ben-Cohen wrote: > On Fri, Jan 27, 2012 at 5:17 PM, Marek Szyprowski > wrote: > > There have been some vmalloc layout changes merged to v3.3-rc1. > > That was dead-on, thanks a lot! Did you managed to fix this issue? > > I did then bump into a different allocation failure which happened > because dma_alloc_from_contiguous() computes 'mask' before capping the > 'align' argument. > > The early 'mask' computation was added in v18 (and therefore exists in > v19 too) and I was actually testing v17 previously, so I didn't notice > it before. Right, thanks for spotting it, I will squash it to the next release. > You may want to squash something like this: > > diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c > index f41e699..8455cb7 100644 > --- a/drivers/base/dma-contiguous.c > +++ b/drivers/base/dma-contiguous.c > @@ -319,8 +319,7 @@ struct page *dma_alloc_from_contiguous(struct device *dev, i > unsigned int align) > { > struct cma *cma = dev_get_cma_area(dev); > - unsigned long pfn, pageno, start = 0; > - unsigned long mask = (1 << align) - 1; > + unsigned long mask, pfn, pageno, start = 0; > int ret; > > if (!cma || !cma->count) > @@ -329,6 +328,8 @@ struct page *dma_alloc_from_contiguous(struct device *dev, i > if (align > CONFIG_CMA_ALIGNMENT) > align = CONFIG_CMA_ALIGNMENT; > > + mask = (1 << align) - 1; > + > pr_debug("%s(cma %p, count %d, align %d)\n", __func__, (void *)cma, > count, align); > Best regards -- Marek Szyprowski Samsung Poland R&D Center