On Wed, 24 Jul 2013 12:51:16 +0300 "Michael S. Tsirkin" <m...@redhat.com> wrote:
> On Wed, Jul 24, 2013 at 09:01:51AM +0200, Gerd Hoffmann wrote: > > On 07/24/13 08:01, Michael S. Tsirkin wrote: > > > It turns out that some 32 bit windows guests crash > > > if 64 bit PCI hole size is >2G. > > > > Ah, *that* is the reason for winxp crashing with a 64bit hole. > > > > Current seabios uses a slightly different approach: the 64bit hole is > > present only in case it is actually used to map bars there, and seabios > > tries to fit everything into the 32bit hole first. > > Yes. But this doesn't work with device hotplug. > > > > Limit it to 2G for piix and q35 by default, > > > add properties to let management override the hole size. > > > > > > Examples: > > > -global i440FX-pcihost.pci_hole64_size=137438953472 > > > > Do we really want specify this in bytes? Using megabytes or gigabytes > > instead looks more sane to me. > > > > cheers, > > Gerd > > I think that arbitrarily saying size is in gigabytes is > confusing to users (in particular because there's no > documentation for properties except their type). > I intend to send a patch to properties that allows writing > "size=1G" instead. for size property you could take patches: [PATCH 04/16] qapi: make visit_type_size fallback to type_int [PATCH 05/16] qdev: Add SIZE type to qdev properties from [PATCH 00/16 RFC v6] ACPI memory hotplug
