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=-11.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,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 A5C0AC47247 for ; Tue, 5 May 2020 11:08:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8585C206D7 for ; Tue, 5 May 2020 11:08:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588676903; bh=rTS4sAWRIKpMhi7hEVazwFvLHrINZkWfgmyIZpewiR4=; h=Subject:To:From:Date:List-ID:From; b=F3esuRID2drwQE/klEIPNv4t59Z+ZHiEtXUNcRDT9O+jCkOoP+D9pNkmS8hiJWCxw lKa0oFSG3E1VMCMp1CQeF1jKZJsFGS4GvIE8VUXGo+QXefwIdQeFyZTVhRXUgjNrbX RkLaEpdXwHjw+KEnwC3Ejpt4Fe/S6zZmVkozXLoE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728565AbgEELIX (ORCPT ); Tue, 5 May 2020 07:08:23 -0400 Received: from mail.kernel.org ([198.145.29.99]:48114 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728584AbgEELIW (ORCPT ); Tue, 5 May 2020 07:08:22 -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 37570206B8; Tue, 5 May 2020 11:08:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588676900; bh=rTS4sAWRIKpMhi7hEVazwFvLHrINZkWfgmyIZpewiR4=; h=Subject:To:From:Date:From; b=IF7sLI2KQ/4GWZ5TFXli1G6eCEq2/CtbdSE4H32N34aSlkuNHltVgC2WJxTlM/sTI Pylhy81IX8OdIJoLBVqdhJQDzUVWpHg5S0v/sOxMeRAnz8YwyLdTIRXQ0jDGp/cnql iYKRGHGKrQYi4OGzA9E5RS6bryB9C01eFriJoKZg= Subject: patch "usb: usbfs: correct kernel->user page attribute mismatch" added to usb-linus To: jeremy.linton@arm.com, gregkh@linuxfoundation.org, stable@vger.kernel.org From: Date: Tue, 05 May 2020 13:08:06 +0200 Message-ID: <158867688647127@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is a note to let you know that I've just added the patch titled usb: usbfs: correct kernel->user page attribute mismatch to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From 2bef9aed6f0e22391c8d4570749b1acc9bc3981e Mon Sep 17 00:00:00 2001 From: Jeremy Linton Date: Mon, 4 May 2020 15:13:48 -0500 Subject: usb: usbfs: correct kernel->user page attribute mismatch On some architectures (e.g. arm64) requests for IO coherent memory may use non-cachable attributes if the relevant device isn't cache coherent. If these pages are then remapped into userspace as cacheable, they may not be coherent with the non-cacheable mappings. In particular this happens with libusb, when it attempts to create zero-copy buffers for use by rtl-sdr (https://github.com/osmocom/rtl-sdr/). On low end arm devices with non-coherent USB ports, the application will be unexpectedly killed, while continuing to work fine on arm machines with coherent USB controllers. This bug has been discovered/reported a few times over the last few years. In the case of rtl-sdr a compile time option to enable/disable zero copy was implemented to work around it. Rather than relaying on application specific workarounds, dma_mmap_coherent() can be used instead of remap_pfn_range(). The page cache/etc attributes will then be correctly set in userspace to match the kernel mapping. Signed-off-by: Jeremy Linton Cc: stable Link: https://lore.kernel.org/r/20200504201348.1183246-1-jeremy.linton@arm.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/devio.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index 6833c918abce..b9db9812d6c5 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -217,6 +217,7 @@ static int usbdev_mmap(struct file *file, struct vm_area_struct *vma) { struct usb_memory *usbm = NULL; struct usb_dev_state *ps = file->private_data; + struct usb_hcd *hcd = bus_to_hcd(ps->dev->bus); size_t size = vma->vm_end - vma->vm_start; void *mem; unsigned long flags; @@ -250,9 +251,7 @@ static int usbdev_mmap(struct file *file, struct vm_area_struct *vma) usbm->vma_use_count = 1; INIT_LIST_HEAD(&usbm->memlist); - if (remap_pfn_range(vma, vma->vm_start, - virt_to_phys(usbm->mem) >> PAGE_SHIFT, - size, vma->vm_page_prot) < 0) { + if (dma_mmap_coherent(hcd->self.sysdev, vma, mem, dma_handle, size)) { dec_usb_memory_use_count(usbm, &usbm->vma_use_count); return -EAGAIN; } -- 2.26.2