From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DDE9FC433DF for ; Mon, 15 Jun 2020 06:55:05 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A4D032068E for ; Mon, 15 Jun 2020 06:55:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A4D032068E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 73BBC888E4; Mon, 15 Jun 2020 06:55:05 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id yNu9YK5S5u68; Mon, 15 Jun 2020 06:55:04 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by hemlock.osuosl.org (Postfix) with ESMTP id 754ED8878B; Mon, 15 Jun 2020 06:55:04 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 57732C0888; Mon, 15 Jun 2020 06:55:04 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists.linuxfoundation.org (Postfix) with ESMTP id 58879C016E for ; Mon, 15 Jun 2020 06:55:02 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id 47320226E9 for ; Mon, 15 Jun 2020 06:55:02 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id P-WYTKJeucyi for ; Mon, 15 Jun 2020 06:55:00 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by silver.osuosl.org (Postfix) with ESMTPS id 5F7E0220D0 for ; Mon, 15 Jun 2020 06:55:00 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 82E9968B02; Mon, 15 Jun 2020 08:54:55 +0200 (CEST) Date: Mon, 15 Jun 2020 08:54:55 +0200 From: Christoph Hellwig To: David Rientjes Subject: Re: [patch for-5.8 1/4] dma-direct: always align allocation size in dma_direct_alloc_pages() Message-ID: <20200615065455.GA21248@lst.de> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Cc: Thomas Lendacky , Brijesh Singh , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, Robin Murphy , Christoph Hellwig X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Thu, Jun 11, 2020 at 12:20:28PM -0700, David Rientjes wrote: > dma_alloc_contiguous() does size >> PAGE_SHIFT and set_memory_decrypted() > works at page granularity. It's necessary to page align the allocation > size in dma_direct_alloc_pages() for consistent behavior. > > This also fixes an issue when arch_dma_prep_coherent() is called on an > unaligned allocation size for dma_alloc_need_uncached() when > CONFIG_DMA_DIRECT_REMAP is disabled but CONFIG_ARCH_HAS_DMA_SET_UNCACHED > is enabled. > > Cc: stable@vger.kernel.org > Signed-off-by: David Rientjes > --- > kernel/dma/direct.c | 17 ++++++++++------- > 1 file changed, 10 insertions(+), 7 deletions(-) > > diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c > --- a/kernel/dma/direct.c > +++ b/kernel/dma/direct.c > @@ -112,11 +112,12 @@ static inline bool dma_should_free_from_pool(struct device *dev, > struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, > gfp_t gfp, unsigned long attrs) > { > - size_t alloc_size = PAGE_ALIGN(size); > int node = dev_to_node(dev); > struct page *page = NULL; > u64 phys_limit; > > + VM_BUG_ON(!PAGE_ALIGNED(size)); This really should be a WARN_ON_ONCE, but I've fixed this up before applying. I've also added a prep patch to mark __dma_direct_alloc_pages static as part of auditing for other callers. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu