On 04/08/2012 06:46 PM, Michael S. Tsirkin wrote: > > > > > > > > I'm thinking about this flow: > > > > > > > > FLR the device > > > > for each emulated register > > > > read it from the hardware > > > > if different from emulated register: > > > > update the internal model (for example, disabling MSI in kvm if > > > > needed) > > > > > > If we do it this way we get back the problem this patch > > > is trying to solve: MSIX assigned while device > > > memory is disabled would cause unsupported request errors. > > > > Why is that? FLR would presumably disable MSI in the device, and this > > line would disable it in kvm as well. > > The bug is that device memory is disabled (FLR would do that) > while MSI is enabled in kvm. The fix is to > disable MSI in kvm first. Yes, no need to repeat. My question is whether my pseudo-code does the same and whether or not if it is better (when applied to all emulated config space). > > > Doing this in kernel seems more robust, otherwise > > > we risk losing the device if qemu gets killed > > > before it has restored the registers. > > > > Doesn't the driver have to enable MSIX if it attaches to the device at > > that point, anyway? > > Yes. I'm talking about things like enabling memory, setting up irq register, > etc though. Most of this setup is done by bios. I see. So should we have a pci_reset_function() variant that limits itself to restoring just those bits? -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
