From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: [PATCH 3/6] xen-swiotlb: Fix wrong panic. Date: Fri, 26 Aug 2011 14:44:27 -0400 Message-ID: <1314384270-19850-4-git-send-email-konrad.wilk@oracle.com> References: <1314384270-19850-1-git-send-email-konrad.wilk@oracle.com> Return-path: In-Reply-To: <1314384270-19850-1-git-send-email-konrad.wilk@oracle.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org, xen-devel@lists.xensource.com, JBeulich@novell.com, jeremy@goop.org, ian.campbell@citrix.com, joe@perches.com Cc: Konrad Rzeszutek Wilk , stable@kernel.org List-Id: xen-devel@lists.xenproject.org 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. CC: stable@kernel.org Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/swiotlb-xen.c | 7 ++++--- 1 files changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index d45cbac..ea8c289 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -293,9 +293,10 @@ dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page, /* * 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); -- 1.7.4.1