On 3/14/19 11:10 AM, Oleksandr Andrushchenko wrote: > On 3/14/19 5:02 PM, Boris Ostrovsky wrote: >> On 3/14/19 10:52 AM, Oleksandr Andrushchenko wrote: >>> On 3/14/19 4:47 PM, Boris Ostrovsky wrote: >>>> On 3/14/19 9:17 AM, Oleksandr Andrushchenko wrote: >>>>> From: Oleksandr Andrushchenko <oleksandr_andrushche...@epam.com> >>>>> >>>>> Currently on driver resume we remove all the network queues and >>>>> destroy shared Tx/Rx rings leaving the driver in its current state >>>>> and never signaling the backend of this frontend's state change. >>>>> This leads to the number of consequences: >>>>> - when frontend withdraws granted references to the rings etc. it >>>>> cannot >>>>> be cleanly done as the backend still holds those (it was not >>>>> told to >>>>> free the resources) >>>>> - it is not possible to resume driver operation as all the >>>>> communication >>>>> means with the backned were destroyed by the frontend, thus >>>>> making the frontend appear to the guest OS as functional, but >>>>> not really. >>>> What do you mean? Are you saying that after resume you lose >>>> connectivity? >>> Exactly, if you take a look at the .resume callback as it is now >>> what it does it destroys the rings etc. and never notifies the backend >>> of that, e.g. it stays in, say, connected state with communication >>> channels destroyed. It never goes into any other Xen bus state, so >>> there is >>> no way its state machine can help recovering. >> >> My tree is about a month old so perhaps there is some sort of regression >> but this certainly works for me. After resume netfront gets >> XenbusStateInitWait from backend which causes xennet_connect(). > Ah, the difference can be of the way we get the guest enter > the suspend state. I am making my guest to suspend with: > echo mem > /sys/power/state > And then I use an interrupt to the guest (this is a test code) > to wake it up. > Could you please share your exact use-case when the guest enters suspend > and what you do to resume it?
xl save / xl restore > I can see no way backend may want enter XenbusStateInitWait in my > use-case > as it simply doesn't know we want him to. Yours looks like ACPI path, I don't know how well it was tested TBH. -boris _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
