On Tue, 2007-09-25 at 19:15 +0200, Dor Laor wrote: > At the moment it's not good enough, there is a potential race were the > guest optimistically turn off > the VRING_AVAIL_F_NO_INTERRUPT in the vring_restart and afterwards > finds there are more_used so > it consume them in the poll function. > If in the middle, packets arrive the host will see the flag is off and > send irq. > In that case the above irq handler will report IRQ_NONE. Good point. On the one hand, reporting IRQ_NONE occasionally is not fatal. On the other, it'd be nice to get this right. > It's also not trivial to cancel the optimistic approach in the restart > function since then there might be another race > that will result in missing irq reaching the guest. I did it optimistically because otherwise we need two barriers (and still have a window). > I'll try to think of something better than a hypercall for switching > irq on/off. Erk. That would be v. bad... Thanks, Rusty. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
