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=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 92675C31E45 for ; Thu, 13 Jun 2019 23:19:03 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (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 583162133D for ; Thu, 13 Jun 2019 23:19:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="l7CW3kEb" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 583162133D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 0E0BCE6C; Thu, 13 Jun 2019 23:19:03 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 6EEC1E75 for ; Thu, 13 Jun 2019 23:01:08 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 89395711 for ; Thu, 13 Jun 2019 23:01:06 +0000 (UTC) Received: from [192.168.1.112] (c-24-9-64-241.hsd1.co.comcast.net [24.9.64.241]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C71622147A; Thu, 13 Jun 2019 23:01:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560466866; bh=ijAoTvben3xHdJwjFjc2JVq20l3k6CT0SJjNIni16EE=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=l7CW3kEbIEfMPyQKq84ka0PeuSuwdqPEd/rBwzyb+r1FqLLqyErPP9Iw42L52TmB5 2Uy1rIkSbsHxHYYCWBq3FZuNZTXRsZ2QRyHKWJRpBXggeBKNkX5qMpxYhhmmT5vXeb r3sXe5wfp6Fftm3kLieDRdFmX+o6d0kmUyHdR3fc= Subject: Re: How to resolve an issue in swiotlb environment? To: Alan Stern , Christoph Hellwig , Valentina Manea References: From: shuah Message-ID: <41caad16-3fa1-413b-0d49-594d48b88de4@kernel.org> Date: Thu, 13 Jun 2019 17:01:05 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-Mailman-Approved-At: Thu, 13 Jun 2019 23:19:01 +0000 Cc: Linux-Renesas , "linux-usb@vger.kernel.org" , Oliver Neukum , "linux-block@vger.kernel.org" , "iommu@lists.linux-foundation.org" , shuah X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org On 6/13/19 11:16 AM, Alan Stern wrote: > On Thu, 13 Jun 2019, Christoph Hellwig wrote: > >> On Wed, Jun 12, 2019 at 10:43:11AM -0400, Alan Stern wrote: >>> Would it be okay to rely on the assumption that USB block devices never >>> have block size < 512? (We could even add code to the driver to >>> enforce this, although refusing to handle such devices at all might be >>> worse than getting an occasional error.) >> >> sd.c only supports a few specific sector size, and none of them is >> < 512 bytes: >> >> if (sector_size != 512 && >> sector_size != 1024 && >> sector_size != 2048 && >> sector_size != 4096) { >> ... >> sdkp->capacity = 0; > > Great! So all we have to do is fix vhci-hcd. Then we can remove all > the virt_boundary_mask stuff from usb-storage and uas entirely. > > (I'm assuming wireless USB isn't a genuine issue. As far as I know, it > is pretty much abandoned at this point.) > > Valentina and Shua: Adding SG support to vhci-hcd shouldn't be too > hard. It ought to be possible even without changing the network > protocol. > I will start taking a look at this. Is there a target release in plan to drop virt_boundary_mask stuff? thanks, -- Shuah _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu