From ab2a47bd242d6cdcf6b2b64797f271c6f0a6d338 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 22 Jul 2011 12:51:48 -0400 Subject: [PATCH] xen-swiotlb: Fix wrong panic. 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 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index d45cbacaf6ff..ea8c28950322 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);