From: Stefano Stabellini Date: Fri, 21 Nov 2014 11:10:39 +0000 (+0000) Subject: swiotlb-xen: remove BUG_ON in xen_bus_to_phys X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c884227eaae9936f8ecbde6e1387bccdab5f4e90;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git swiotlb-xen: remove BUG_ON in xen_bus_to_phys On x86 truncation cannot occur because config XEN depends on X86_64 || (X86_32 && X86_PAE). On ARM truncation can occur without CONFIG_ARM_LPAE, when the dma operation involves foreign grants. However in that case the physical address returned by xen_bus_to_phys is actually invalid (there is no mfn to pfn tracking for foreign grants on ARM) and it is not used. Signed-off-by: Stefano Stabellini Reviewed-by: Catalin Marinas Acked-by: Konrad Rzeszutek Wilk CC: stable@vger.kernel.org --- diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 498b6544fd62..153cf1482125 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -96,8 +96,6 @@ static inline phys_addr_t xen_bus_to_phys(dma_addr_t baddr) dma_addr_t dma = (dma_addr_t)pfn << PAGE_SHIFT; phys_addr_t paddr = dma; - BUG_ON(paddr != dma); /* truncation has occurred, should never happen */ - paddr |= baddr & ~PAGE_MASK; return paddr;