From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933981Ab1KJFQG (ORCPT ); Thu, 10 Nov 2011 00:16:06 -0500 Received: from cantor2.suse.de ([195.135.220.15]:42103 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934466Ab1KJDY5 (ORCPT ); Wed, 9 Nov 2011 22:24:57 -0500 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Nov 9 13:27:07 2011 Message-Id: <20111109212707.103679751@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 09 Nov 2011 13:26:29 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Konrad Rzeszutek Wilk Subject: [067/262] xen-swiotlb: Fix wrong panic. In-Reply-To: <20111109212847.GA20838@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Konrad Rzeszutek Wilk commit ab2a47bd242d6cdcf6b2b64797f271c6f0a6d338 upstream. Propagate the baremetal git commit "swiotlb: fix wrong panic" (fba99fa38b023224680308a482e12a0eca87e4e1) in the Xen-SWIOTLB version. wherein swiotlb's map_page wrongly calls panic() when it can't find a buffer fit for device's dma mask. It should return an error instead. Devices with an odd dma mask (i.e. under 4G) like b44 network card hit this bug (the system crashes): http://marc.info/?l=linux-kernel&m=129648943830106&w=2 If xen-swiotlb returns an error, b44 driver can use the own bouncing mechanism. Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Greg Kroah-Hartman --- drivers/xen/swiotlb-xen.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -278,9 +278,10 @@ dma_addr_t xen_swiotlb_map_page(struct d /* * Ensure that the address returned is DMA'ble */ - if (!dma_capable(dev, dev_addr, size)) - panic("map_single: bounce buffer is not DMA'ble"); - + if (!dma_capable(dev, dev_addr, size)) { + swiotlb_tbl_unmap_single(dev, map, size, dir); + dev_addr = 0; + } return dev_addr; } EXPORT_SYMBOL_GPL(xen_swiotlb_map_page);