On Sat, 2007-04-28 at 18:17 +0100, Jon Burgess wrote: > On Fri, 2007-04-27 at 18:06 -0400, Lee Revell wrote: > > On 4/27/07, Jon Burgess wrote: > > > Interesting - I see similar symptoms after upgrading my PC: > > > * old PC was AMD Athlon 64 3000 w/ 2GB of RAM which had no issues > > > * new PC is a Intel Core 2 Duo w/ 4GB of RAM and fails in the way you > > > describe. > > > > Driver using an incorrect DMA mask? > > > > Lee > > It appears the problem is that the driver is using streamed PCI and > needs to explicitly sync the data otherwise it breaks when the SWIOTLB > is in use. A call to pci_unmap_sg() was missing too. > > This patch is against the current v4l-dvb HG tree. > > I've only tested the change with a budget-ci card. > > Jon > > Signed-off-by: Jon Burgess While the above patch works, it seems the underlying causes is that vmalloc_32() is providing memory above 4Gb on x86-64 which is not what the driver expects. This same issue came up a few weeks ago with regards to DRM on radeon http://lkml.org/lkml/2007/4/1/257 Andi Kleen included a patch to ensure vmalloc_32() returns memory <4Gb in a patch which is currently in -mm http://kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.21-rc7/2.6.21-rc7-mm2/broken-out/x86_64-mm-vmalloc-32.patch With this patch applied the current driver appears to work OK. Attached is a smaller patch against v4l-dvb which just adds the missing pci_unmap_sg() call. Jon Signed-off-by: Jon Burgess