On Mon, Mar 16, 2009 at 6:13 PM, Luis R. Rodriguez <mcgrof@xxxxxxxxx> wrote: > On Mon, Mar 16, 2009 at 5:35 PM, FUJITA Tomonori > <fujita.tomonori@xxxxxxxxxxxxx> wrote: >> On Mon, 16 Mar 2009 12:15:37 -0700 >> "Luis R. Rodriguez" <mcgrof@xxxxxxxxx> wrote: >> >>> I've run into "PCI-DMA: Out of IOMMU space" messages after loading and >>> unloading a module 30 times. The interesting thing is this only >>> happens if I have > 4 GB of memory. The box this occurs has AMD Phenom >>> quad core CPU so I take it a harware IOMMU is being used. Below are >>> example relevant messages with > 4 GB and then < 4 GB of memory. The >>> driver I tested this with was ath9k. It could be an issue perhaps with >>> ath9k but I am unable to find an issue in our probe/removal. >>> >>> Could this be an issue with the AMD IOMMU used? Or is it more likely a >>> driver issue? >> >> ath9k wants DMA_32BIT_MASK, right? If so, GART IOMMU does nothing on a >> system with < 4GB memory since ath9k can access to all the memory >> addresses directly. With >4GB memory, GART needs to remap an address >> higher than 4GB because ath9k wants DMA_32BIT_MASK. >> >> From a quick look, ath9k doesn't call pci_unmap_single for rx >> buffers. Though I might be wrong because I don't know anything about >> the driver. > > You seem to be right actually, we were calling pci_unmap_single() for > rx buffers on the RX tasklet but never for the simple case of removing > the module. Will test it out in a bit. That was it, thanks.. will propagate the patch. Luis -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
