On Thu, 22 Jul 2010 08:44:42 +0900 FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx> wrote: > On Wed, 21 Jul 2010 10:13:34 -0700 > Alok Kataria <akataria@xxxxxxxxxx> wrote: > > > > Basically, you want to add hot-plug memory and enable swiotlb, right? > > > > Not really, I am planning to do something like this, > > > > @@ -52,7 +52,7 @@ int __init pci_swiotlb_detect(void) > > > > /* don't initialize swiotlb if iommu=off (no_iommu=1) */ > > #ifdef CONFIG_X86_64 > > - if (!no_iommu && max_pfn > MAX_DMA32_PFN) > > + if (!no_iommu && (max_pfn > MAX_DMA32_PFN || hotplug_possible())) > > swiotlb = 1; > > Always enable swiotlb with memory hotplug enabled? Wasting 64MB on a > x86_64 system with 128MB doesn't look to be a good idea. I don't think > that there is an easy solution for this issue though. btw, you need more work to enable switch on the fly. You need to change the dma_ops pointer (see get_dma_ops()). It means that you need to track outstanding dma operations per device, locking, etc. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
