Re: kvm PCI assignment & VFIO ramblings

On Tue, Aug 23, 2011 at 07:35:37PM -0400, Benjamin Herrenschmidt wrote:

On Tue, 2011-08-23 at 15:18 +0200, Roedel, Joerg wrote:

quoted

Hmm, good idea. But as far as I know the hotplug-event needs to be in
the guest _before_ the device is actually unplugged (so that the guest
can unbind its driver first). That somehow brings back the sleep-idea
and the timeout in the .release function.

That's for normal assisted hotplug, but don't we support hard hotplug ?
I mean, things like cardbus, thunderbolt (if we ever support that)
etc... will need it and some platforms do support hard hotplug of PCIe
devices.

(That's why drivers should never spin on MMIO waiting for a 1 bit to
clear without a timeout :-)

Right, thats probably the best semantic for this issue then. The worst
thing that happens is that the admin crashed the guest.

	Joerg

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