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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1B9E8C52D7C for ; Mon, 12 Aug 2024 11:48:43 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [127.0.0.1]) by lists.ozlabs.org (Postfix) with ESMTP id 4WjCTQ3dlvz2xWc; Mon, 12 Aug 2024 21:48:42 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=139.178.84.217; helo=dfw.source.kernel.org; envelope-from=cmarinas@kernel.org; receiver=lists.ozlabs.org) Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4WjBtx70lKz2xT9 for ; Mon, 12 Aug 2024 21:22:17 +1000 (AEST) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id A3A7B60C17; Mon, 12 Aug 2024 11:22:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0886CC32782; Mon, 12 Aug 2024 11:22:12 +0000 (UTC) Date: Mon, 12 Aug 2024 12:22:10 +0100 From: Catalin Marinas To: Baruch Siach Cc: Christoph Hellwig , Marek Szyprowski , Will Deacon , Robin Murphy , iommu@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, Petr =?utf-8?B?VGVzYcWZw61r?= , Ramon Fried , Elad Nachman Subject: Re: [PATCH v6 RESED 1/2] dma: replace zone_dma_bits by zone_dma_limit Message-ID: References: <17c067618b93e5d71f19c37826d54db4299621a3.1723359916.git.baruch@tkos.co.il> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Post: List-Subscribe: , , List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <17c067618b93e5d71f19c37826d54db4299621a3.1723359916.git.baruch@tkos.co.il> On Sun, Aug 11, 2024 at 10:09:35AM +0300, Baruch Siach wrote: > From: Catalin Marinas > > Hardware DMA limit might not be power of 2. When RAM range starts above > 0, say 4GB, DMA limit of 30 bits should end at 5GB. A single high bit > can not encode this limit. > > Use plain address for DMA zone limit. > > Since DMA zone can now potentially span beyond 4GB physical limit of > DMA32, make sure to use DMA zone for GFP_DMA32 allocations in that case. > > Signed-off-by: Catalin Marinas > Co-developed-by: Baruch Siach > Signed-off-by: Baruch Siach You might want to say that no functional change is expected with this patch. The patch looks fine. Reviewed-by: Catalin Marinas