Re: [RFC PATCH 00/10] Remove skb_dma_map/unmap calls
From: David Miller <davem@davemloft.net>
Date: 2009-11-30 07:40:31
From: Alexander Duyck <redacted> Date: Tue, 24 Nov 2009 17:20:12 -0800
This patch series removes the skb_dma_map and skb_dma_unmap function calls. The reason for this change is because the use of skb_dma_map/unmap can lead to serious issues when HW IOMMU is enabled. This is because each mapping of the skb with a HW IOMMU enabled results in a new set of DMA mappings. This in turn leads to issues when skbs are cloned for uses such as bridging or pktgen because each transmitting device will update the skb shared info structure resulting in some mappings being overwritten, and others being freed multiple times. I am looking for input specifically on the tg3, be2net, and bnx2 driver patches as I am not very familiar with them and I am not certain if additional changes are required. I have included the changes for the Intel wired Ethernet drivers as a reference.
These changes look good, but at least one of them does not apply to current net-2.6 Can you respin this against current sources? Thanks a lot for doing this work Alexander.