i suspect so, threadpool makes all things to be more async as they were before and proper lockings does matter, i could test any patches at evening, and i must admit i never get well uderstanding on virtio device operations yet (in terms of virtio ring :) On Friday, April 29, 2011, Pekka Enberg <penberg@xxxxxxxxxx> wrote: > On Fri, Apr 29, 2011 at 1:02 PM, Cyrill Gorcunov <gorcunov@xxxxxxxxx> wrote: >> So, if I understand all the things correct -- making virtio devices to >> belong separated irqs >> issued some race conditions on read\write operations between host and >> guest and adding >> thread pool revealed it, right? (because previously we were doing all >> the work inside i/o >> path on guest site). > > So does reverting commit a37089da817ce7aad9789aeb9fc09b68e088ad9a > ("kvm tools: Use threadpool for virtio-net") fix things? I think the > problem here is that now RX path relies on VIRTIO_PCI_QUEUE_NOTIFY to > happen in order for it to trigger KVM_IRQ_LINE which is wrong. Using > shared IRQs obviously masks the problem which is why reverting > Cyrill's commit makes the problem go away. > > Pekka > -- 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