[Qemu-devel] Re: [PATCH 4/5] Make MMIO address page aligned in guest.

[Kevin O'Connor]

On Sun, Oct 11, 2009 at 08:59:06PM +0200, Gleb Natapov wrote:
> MMIO of some devices are not page aligned, such as some EHCI
[...]
> @@ -158,6 +159,12 @@ static void pci_bios_init_device(u16 bdf)
>                  *paddr = ALIGN(*paddr, size);
>                  pci_set_io_region_addr(bdf, i, *paddr);
>                  *paddr += size;
> +                if (kvm_para_available()) {
> +                    /* make memory address page aligned */
> +                    /* needed for device assignment on kvm */
> +                    if (!(val & PCI_BASE_ADDRESS_SPACE_IO))
> +                        *paddr = (*paddr + 0xfff) & 0xfffff000;
> +               }
>              }

I don't see an issue with doing this.  However, I can't see why it
would be just done for kvm - why not do it for all hosts?

Also, please use the ALIGN() macro - something like:
      *paddr = ALIGN(*paddr, PAGE_SIZE);

-Kevin