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 smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (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 CEC05C433FE for ; Mon, 28 Feb 2022 11:04:47 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 6A76340892; Mon, 28 Feb 2022 11:04:47 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id nrYAE-kbNDjc; Mon, 28 Feb 2022 11:04:46 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp4.osuosl.org (Postfix) with ESMTPS id 4C33540890; Mon, 28 Feb 2022 11:04:46 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 2D1E4C0033; Mon, 28 Feb 2022 11:04:46 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 67A1CC001A for ; Mon, 28 Feb 2022 11:04:45 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 409184028D for ; Mon, 28 Feb 2022 11:04:45 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 7CEYgvnWw4yE for ; Mon, 28 Feb 2022 11:04:44 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by smtp2.osuosl.org (Postfix) with ESMTPS id 071A540012 for ; Mon, 28 Feb 2022 11:04:43 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 532E968AFE; Mon, 28 Feb 2022 12:04:38 +0100 (CET) Date: Mon, 28 Feb 2022 12:04:38 +0100 From: Christoph Hellwig To: Robin Murphy Subject: Re: [PATCH] dma-mapping: remove CONFIG_DMA_REMAP Message-ID: <20220228110438.GA10232@lst.de> References: <20220227143533.357356-1-hch@lst.de> <4802e9fd-733f-3246-92f3-05f590e05d37@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <4802e9fd-733f-3246-92f3-05f590e05d37@arm.com> User-Agent: Mutt/1.5.17 (2007-11-01) Cc: x86@kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, will@kernel.org, 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 Mon, Feb 28, 2022 at 10:32:54AM +0000, Robin Murphy wrote: > Is it even possible to hit this case now? From a quick look, all the > architectures defining HIGHMEM either have an explicit dependency on MMU or > don't allow deselecting it anyway (plus I don't see how HIGHMEM && !MMU > could work in general), so I'm pretty sure this whole chunk should go away > now. > > With that (or if there *is* some subtle wacky case where PageHighmem() can > actually return true for !MMU, a comment to remind us in future), No, you're right - I don't think we can support highmem on !CONFIG_MMU. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu