On 20/07/2017 9:52, Gerd Hoffmann wrote:
On Wed, 2017-07-19 at 16:20 +0300, Aleksandr Bezzubikov wrote:
Now PCI bridges (and PCIE root port too) get a bus range number in
system init,
basing on currently plugged devices. That's why when one wants to
hotplug another bridge,
it needs his child bus, which the parent is unable to provide.
The suggested workaround is to have vendor-specific capability in
RedHat generic pcie-root-port
that contains number of additional bus to reserve on BIOS PCI init.
Hi Gerd,
Thanks for looking into this.
Where is the qemu patch for this?
On the way, Aleksandr is working on it, should
be ready soon.
What about window sizes? IIRC there was a plan to provide allocation
hints for them too ...
Yes, is in my TODO list, however not as part of Aleksandr's series
which aims to provide PCIe-PCI bridge hotplug support.
I should mention that for this case both Windows and Linux guests
(modern OSes) trigger correctly IO/MEM resource re-balancing
process and succeeds to complete the hotplug operation.
Thanks,
Marcel
cheers,
Gerd