On Wed, Sep 18, 2013 at 03:09:01PM +0900, Takao Indoh wrote:
> + /*
> + * In the case of kdump, ioremap is needed because root-entry table
> + * exists in first kernel's memory area which is not mapped in second
> + * kernel
> + */
> + root = (struct root_entry *)ioremap(addr, PAGE_SIZE);
> + if (!root)
> + return;
> +
> + for (bus = 0; bus < ROOT_ENTRY_NR; bus++) {
> + if (!root_present(&root[bus]))
> + continue;
> +
> + context = (struct context_entry *)ioremap(
> + root[bus].val & VTD_PAGE_MASK, PAGE_SIZE);
> + if (!context)
> + continue;
> +
> + for (devfn = 0; devfn < CONTEXT_ENTRY_NR; devfn++) {
> + if (!context_present(&context[devfn]))
> + continue;
> +
> + dev = pci_get_domain_bus_and_slot(segment, bus, devfn);
> + if (!dev)
> + continue;
> +
> + if (!pci_reset_bus(dev->bus)) /* go to next bus */
> + break;
> + else /* Try per-function reset */
> + pci_reset_function(dev);
> +
> + }
> + iounmap(context);
> + }
> + iounmap(root);
I am not convinced that this is the right approach. If a device wasn't
translated by VT-d in the old kernel doesn't mean it will not be
translated in the new kernel. How about unconditionally resetting all
PCI busses and/or functions here before IOMMU initialization proceeds?
Joerg
