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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 9576BC3A5A8 for ; Wed, 4 Sep 2019 07:05:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5F91D2339E for ; Wed, 4 Sep 2019 07:05:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567580711; bh=BvhCnpCI7Jpy8VXdwe7ysGKs1koYaDcnvbTLdLeJAiI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=b+/50nIqZG4v2nhO5Nbfo0H39ZJUC71t9SR2gPqeHKteUqYa609Ioqx9Zrh0IB1tK zpnRRBetH9cFfA1mh9fvCnilkgfqdFv2kXW+xnLlGfQFrkrDpYFba1vh+yh1MfHdb6 8bkApJ7sN53wWg/SUAu2pI1mBK7KEOKcqvzEwkcU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727499AbfIDHFK (ORCPT ); Wed, 4 Sep 2019 03:05:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:59078 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725840AbfIDHFK (ORCPT ); Wed, 4 Sep 2019 03:05:10 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 839BA22CED; Wed, 4 Sep 2019 07:05:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567580710; bh=BvhCnpCI7Jpy8VXdwe7ysGKs1koYaDcnvbTLdLeJAiI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=KDNtYyrNQqprj/svcXeemD0AdjchjOU1HueB3PHYRzg1CWgUOhmRR3xIAzLa8MtBL 2pX3HkJAEdYEMJbc+Nz6dO/erZRU6MjlLS87RUKAouSbAngHdA4vG8eDNn8LprrLPI q1s3lHLi/AQNrlMAKdC3f2BXSMfC6zN0DOXT/oZs= Date: Wed, 4 Sep 2019 09:05:07 +0200 From: Greg KH To: Gavin Li Cc: linux-usb@vger.kernel.org, Gavin Li Subject: Re: [PATCH] usb: devio: fix mmap() on non-coherent DMA architectures Message-ID: <20190904070507.GA18791@kroah.com> References: <20190801220436.3871-1-gavinli@thegavinli.com> <20190802121416.GA20689@kroah.com> <20190805151713.GA7067@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190805151713.GA7067@kroah.com> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Mon, Aug 05, 2019 at 05:17:13PM +0200, Greg KH wrote: > On Fri, Aug 02, 2019 at 10:57:00AM -0700, Gavin Li wrote: > > usbfs mmap() looks like it was introduced for 4.6 in commit > > f7d34b445abc, so it should probably be backported to 4.9 and onwards. > > This issue has been present since the introduction of the feature. > > > > One sidenote: this patch will cause the following warning on x86 due > > to dmap_mmap_coherent() trying to map normal memory in as uncached: > > > > x86/PAT: ... map pfn RAM range req uncached-minus for [mem > > 0x77b000000-0x77b210fff], got write-back > > > > This warning is harmless, as x86 is DMA coherent and the memory gets > > correctly mapped in as write-back. I will submit a patch to the DMA > > mapping team to eliminate this warning. > > Let me know what the git commit id of that patch is, I will wait for it > to hit the tree before adding this one. Dropping this patch from my queue now, please feel free to resend when you have refreshed it against the latest tree. thanks, greg k-h